FS198 WSM C01 - 1

CAUTION
In order to reduce the chance of personal injury and/or property damage, carefully observe
the instructions that follow:
The service manuals of Isuzu Motors America Inc. are intended for use by professional,
qualified technicians. Attempting repairs or service without the appropriate training, tools,
and equipment could cause injury to you or others. This could also damage the vehicle, or
cause the vehicle to operate improperly.
Proper vehicle service and repair are important to the safety of the service technician and to
the safe, reliable operation of all motor vehicles. If you need to replace a part, use the same
part number or an equivalent part. Do not use a replacement part of lesser quality.
The service procedures we recommend and describe in this service manual are effective
methods of performing service and repair. Some of the procedures require the use of tools
that are designed for specific purposes.
Accordingly, any person who intends to use a replacement part, a service procedure, or a
tool that is not recommended by Isuzu, must first establish that there is no jeopardy to
personal safety or the safe operation of the vehicle.
This manual contains various CAUTIONS and NOTICES that you must observe carefully in
order to reduce the risk of personal injury during service or repair. Improper service or
repair may damage the vehicle or render the vehicle unsafe. These CAUTIONS and NOTICES
are not exhaustive. Isuzu can not possibly warn of all the potentially hazardous
consequences of your failure to follow these instructions.
This manual covers service procedures to vehicles that are equipped with a Supplemental
Inflatable Restraint (SIR). Refer to the CAUTIONS in Cautions and Notices and In Restraints.
Refer to SIR component and wiring location views in Restraints before performing a service
on or around SIR components or wiring. Failure to follow these CAUTIONS could cause air
bag deployment, personal injury, or otherwise unneeded SIR repairs.
In order to help avoid accidental air bag deployment and personal injury, whenever you
service a vehicle that requires repair of the SIR and another vehicle system, we recommend
that you first repair the SIR, then go on to the other system.
BLANK
New Style Service Manual Structure
This new style service manual is constructed with the following
10 sections:
0. General Information
1. Heating, Ventilation, and Air Conditioning (HVAC)
2. Steering
3. Suspension
4. Driveline and Axle
5. Brakes
6. Engine
7. Transmission
8. Body and Accessories
9. Restraints
The following table gives the previous service manual sub-sections with
the name of the new section and sub-section. Almost all of the diagnosis
that was in section 8A is now located in its applicable sub-section.
Truck Service Manual Sub-Section to Section
and Sub-Section Conversion Table
Old New
Old Sub-Section Section Name Sub-Section Name
Sub-Section Section \
OA General Information 0 General Information General Information
Maintenance and Maintenance and
OB Lubrication 0 General Information Lubrication
OC Vibration Diagnosis 0 General Information Vibration Diagnosis
Heating and Ventilation
1A Heating and Ventilation 1 HVAC (Non A/C)
Heating, Ventilation, and HVAC systems with Air

1B Air Conditioning 1 HVAC Conditioning
HVAC systems with Air
1D A/C Compressors 1 HVAC Conditioning
Frame and Underbody, and
2A Frame and Bumpers 8 Body and Accessories Bumpers
3A Front Wheel Alignment 3 Suspension Wheel Alignment
3B,3B1A, Power Steering Gear and
3B1B Pump 2 Steering Power Steering System
3B3 Steering Linkage 2 Steering Steering Linkage
3C Front Suspension 3 Suspension Front Suspension
3D Rear Suspension 3 Suspension Rear Suspension
3E Tires and Wheels 3 Suspension Tires and Wheels.
Steering Wheel and
3F Steering Columns 2 Steering Column
4A Propeller Shaft 4 Driveline/Axle Propeller Shaft
4B Rear Axle and Differential 4 Driveline/Axle Rear Drive Axle
Front Drive Axles and Front Wheel Drive Shafts
4C Differential 4 Driveline/Axle and Front Drive Axle
5 Hydraulic Brakes 5 Brakes Hydraulic Brakes
5A Master Cylinder 5 Brakes Hydraulic Brakes
5B Front Disc Brakes 5 Brakes Disc Brakes
5C Drum Brakes 5 Brakes Drum Brakes
Hydraulic or Vacuum
5D Booster 5 Brakes Hydraulic Brakes
5E Antilock Brakes 5 Brakes Antilock Brakes
5F Parking Brake 5 Brakes Parking Brake
6, 6A Engine Mechanical 6 Engine Engine Mechanical

Engine Cooling and
6B Radiator 6 Engine Engine Cooling
6C Engine Fuel 6 Engine Engine Controls
6D Engine Electrical 6 Engine Engine Electrical
Driveability and Emissions 6
Engine Controls
6F Exhaust System 6
Exhaust System
6H Vacuum Pump 6 Engine Vacuum Pump
6J Turbocharger 6 Engine Turbocharger
Automatic Transmission
and
Transmission/Transfer
7A Automatic Transmission 7 Transmission/Transaxle Case Unit Repair Manual
Truck Service Manual Sub-Section to Section
and Sub-Section Conversion Table (cont'd)
Old New
Old Sub-Section Section Name Sub-Section Name
Sub-Section Section
Manual Transmission and
7B Manual Transmission 7 Transmission/Transaxle Case Unit Repair Manual
7C Clutch 7 Transmission/Transaxle Clutch
Transfer Case and
7D Transfer Case 4 Driveline/Axle Case Unit Repair Manual
8B Lighting Systems 8 Body and Accessories Lighting Systems
Instrument Panel and Instrument Panel, Gages
8C Gages 8 Body and Accessories and Console
Refer to the Index at the
8D Chassis Electrical 8 end of the manual
8E Wipers and Washers 8 Body and Accessories Wiper/Washer Systems
9A Audio Systems 8 Body and Accessories Entertainment
9B Cruise Control 8 Body and Accessories Cruise Control
9E Engine Coolant Heater 6 Engine Engine Cooling
9F Luggage Carrier 8 Body and Accessories Roof
Supplemental Inflatable Supplemental Inflatable
9J Restraint 9 Restraints Restraints
9K Remote Keyless Entry 8 Body and Accessories Keyless Entry
10A1 Doors 8 Body and Accessories Doors
8 Body and Accessories Seats
10A2 Seats
9 Restraints Seat Belts
10A3 Stationary Windows 8 Body and Accessories Stationary Glass
10A4 Interior Trim 8 Body and Accessories Exterior/Interior Trim
10A5 Endgate 8 Body and Accessories Body Rear End
10B Cab and Body Refer to the Index at the
Maintenance
end of the manual

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1998 Medium Duty THick
FSR, FTR, FVR
Service Manual
Volume 1
This manual provides information on the diagnosis, the service procedures, the adjustments, and the
specifications for the 1998 Isuzu Medium Duty Truck.
The technicians who understand the material in this manual and in the appropriate Dealer Service Bulletins better
service the vehicle owners.
When this manual refers to a brand name, a part number, or a specific tool, you may use an equivalent product in
place of the recommended item. All information, illustrations and specifications in this manual are based on the
latest product information available at the time of publication approval. Isuzu reserves the right to make changes
at any time without notice.
Published by
ISUZU MOTORS AMERICA, INC.
1998 ISUZU MOTORS AMERICA, INC. ALL RIGHTS RESERVED

The information cutoff date is 12/1/97. LITHO IN U.S.A.
No part of this manual may be reproduced, stored in any retrieval system, or transmitted in any form or by any means
(including but not limited to electronic, mechanical, photocopying, and recording) without the prior written permission of
Isuzu Motors America, Inc. This applies to all text, illustrations, and tables.
BLANK
Table of Contents
Volume 1 Suspension..............................
Suspension General Diagnosis,
Preface........................................................................i
Cautions and Notices.................................................3 Wheel Alignment........................
General Information...........................................0-1 Front Suspension.......................
General Information................................................0-3 Rear Suspension.......................
Maintenance and Lubrication................................0-33 Tires and Wheels......................,
Vibration Diagnosis and Correction Air
......................0-51 Suspension...........................
HVAC.........................................................................1-1 Driveline/Axle...........................
Heating and Ventilation (Non-A/C)..........................1-3 Propeller
Shaft...........................
HVAC Systems with A/C -
Rear Drive Axle..........................

Manual........................1-57
Body and Accessories......................................8-1 Rear Axle Controls.....................
Lighting Systems
....................................................8-7 Brakes.........................................
Wipers/Washer Systems.....................................8-103 Hydraulic
Brakes........................
Disc
Entertainment.....................................................8-123 Brakes................................
Wiring Park Brakes...............................
Systems...................................................8-143
Instrument Panel, Gauges and Console.............8-283 Air Brakes
..................................
Air
Horns..................................................................8-351 Drums..................................,
Exterior Trim........................................................8-361 Air
Compressor.........................
Antilock Brake System
Waterleaks..........................................................8-363 ..............
Stationary Windows............................................8-365 Air Antilock Brake System
........
Bumpers..............................................................8-373
Body Front End
...................................................8-377
Volume 3
Doors..................................................................8-399 Preface................................................
Seats...................................................................8-431
Cautions and Notices.........................
Interior
Trim.........................................................8-441 Engine..................................................
Plastic Panel Information and Repair.................8-453 Engine
Cooling..................................
Engine
Paint/Coatings.....................................................8-455 Electrical................................
Frame and Underbody........................................8-463 Engine Controls 7.8L.......................
-
Collision
Repair...................................................8-485 Engine Exhaust..................................
Restraints...............................................................9-1 Engine, On-vehicle Service ................

Seat Belts...............................................................9-3 Engine Overhaul.................................
Water Pump.......................................
Volume 2 Fuel
System.......................................
Fuel
Preface................................................... .......1 Injection......................................
Cautions and Notices............................ .......3
Diesel Electrical..................................
Steering ................................................. ...2-1 Emission and Electrical Diagnosis
.....
Power Steering System........................ ...2-3 Turbocharger
......................................
Steering Linkage (Non-Rack & Pinion). .2-53 Transmission/Transaxle...............
Steering Wheel and Column -Tilt......... .2-63 Manual Transmission -
Medium Duty.
Automatic Transmission -
Allison.......
Clutch.................................................
Manual Transmission Overhaul..........
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Cautions and Notices
Cautions and Notices..........................................3 Safety Glasses and Compressed

Air
Definition of Caution, Notice, and Important......3 Caution.......................................
Safety Goggles and Fuel Caution.......
ABS Handling
Caution........................................3 Vehicle Lifting
Battery Disconnect Caution.........................
Caution......................
Window Removal Caution
Brake Dust Caution................................... ...................
Work Stall Test Caution
Brake Fluid Caution .......................
.................................. Defective Scan Tool Notice.................
Clutch Dust Caution
.................................. Fastener Notice....................................
Fuel and EVAP Pipe Caution...................
Fuel Pressure
Fuel Gauge Leak Caution Notice...........................
........................ Handling ESD Sensitive Parts Notice.
Fuel Pipe Fitting Caution..........................
Ignition OFF When Disconnecting
Fuel Storage Caution................................
Battery
Gasoline/Gasoline Vapors Caution........... Notice..................................
Nylon Fuel Lines
Moving Parts and Hot Surfaces Caution, Notice......................
PCM and ESD
Road Test Caution Notice..........................
.................................... Single Cylinder Flooding Notice..........
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(998 -
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Preface Cautions and Notices - 3

IMPORTANT Defined
Definition of Caution, Notice, IMPORTANT statements emphasize necessary
a
and Important characteristic of

diagnostic or repair procedure.
a
The diagnosis and repair procedures in the Isuzu IMPORTANT statements are designed to do
Service Manual contain both general and specific the following:
Cautions, Notices, and Importants. Isuzu is dedicated Clarify a procedure
to the presentation of service information that helps
Present additional information for accomplishing
the technician to diagnose and repair the systems a procedure
necessary for the proper operation of the vehicle,
however, certain procedures may present a hazard

Give insight into the reason or reasons for
to the technician if they are not followed in the performing a procedure in the manner
recommended manner. Cautions, Notices, and recommended
Importants are elements designed to prevent these .
Present information that will help to accomplish
hazards, however, not all hazards can be foreseen. a procedure in a more effective manner
This information is placed at strategic locations within

Present information that gives the technician
the service manual. This information is designed to
the benefit of past experience in accomplishing
prevent the following from occurring:
a procedure with greater ease
Serious bodily injury to the technician

Damage to the vehicle ABS Handling Caution

Unnecessary vehicle repairs Caution: Certain components In the Antilock

Unnecessary component replacement Brake System (ABS) are not intended to be

Improper repair or replacement of vehicle serviced individually. Attempting to remove or
components. Any caution or notice that appears disconnect certain system components may
in general information is referenced from the result in personal Injury and/or Improper system
individual service categories. operation. Only those component with approved
CAUTION Defined removal and Installation procedures should
When encountering a CAUTION, you will be asked be serviced.
to take a necessary action or not to take a
prohibited action. If a CAUTION is not heeded, the Battery Disconnect Caution
following consequences may occur:
Caution: Before servicing any electrical
Serious bodily injury to the technician

component, the ignition key must be in the OFF

Serious bodily injury to other technicians in the or LOCK position and all electrical loads must be
workplace area OFF, unless instructed otherwise in these

Serious bodily injury to the driver and/or procedures. If a tool or equipment could easily
passenger(s) of the vehicle, if the vehicle has come in contact with a live exposed electrical
been improperly repaired terminal, also disconnect the negative battery
NOTICE Defined cable. Failure to follow these precautions may
Notices call special attention to a necessary action cause personal injury and/or damage to the
or to a prohibited action. If a NOTICE is not heeded, vehicle or its components.
the following consequences may occur:
Brake Dust Caution

Damage to the vehicle

Unnecessary vehicle repairs Caution: Avoid taking the following actions when

Unnecessary component replacement you service wheel brake parts:

Improper operation or performance of the Do not grind brake linings.

system or component under repair

Do not sand brake linings.
.
Damage to any systems or components which Do not clean wheel brake parts with a dry

are dependent upon the proper operation of the brush or with compressed air.
system or component under repair Some models or aftermarket brake parts may

Improper operation or performance of any contain asbestos fibers which can become
systems or components which are dependent airborne In dust. Breathing dust with asbestos
upon the proper operation or performance of fibers may cause serious bodily harm. Use a
the system or component under repair water-dampened cloth in order to remove any

Damage to fasteners, basic tools, or dust on brake parts. Equipment is available
special tools commercially in order to perform this washing

The leakage of coolant, lubricant, or other function. These wet methods prevent fibers from
vital fluids becoming airborne.
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MD-lsuzu
4 -
Cautions and Notices Preface
Brake Fluid Caution During normal operation, the 0-rings located in

the female connector will swell and may prevent
Caution: Brake fluid may be irritating to the
proper reconnectlon if not lubricated.
skin or eyes. In case of contact, take the
following actions: Fuel Storage Caution

Eye contactrinse eyes thoroughly Caution: Do not drain the fuel into an open
with water. container. Never store the fuel In an open

Skin contactwash skin with soap container due to the possibility of a fire or
and water. an explosion.
Clutch Dust Caution Gasoline/Gasoline Vapors Caution
Caution: When servicing clutch parts, do not Caution: Gasoline or gasoline vapors are highly
create dust by grinding or sanding the clutch flammable. A fire could occur if an ignition
disc or by cleaning parts with a dry brush or source is present. Never drain or store gasoline
with compressed air. A water-dampened or diesel fuel In an open container, due to the
clothNOT SOAKEDshould be used. The clutch possibility of fire or explosion. Have a dry
disc contains asbestos fibers which can become chemical (Class B) fire extinguisher nearby.
airborne If dust Is created during servicing.
Breathing dust containing asbestos fibers may Moving Parts and Hot Surfaces Caution
cause serious bodily harm. Caution: While working around a running engine,
Fuel and EVAP Pipe Caution avoid contact with moving parts and hot surfaces
to prevent possible bodily injury.
Caution: In order to Reduce the Risk of Fire and
Personal Injury observe the following Items: Road Test Caution
Replace all nylon fuel pipes that are nicked,

Caution: Road test a vehicle under safe
scratched or damaged during Installation, Do conditions and while obeying all traffic laws. Do
Not attempt to repair the sections of the not attempt any maneuvers that could jeopardize
nylon fuel pipes vehicle control. Failure to adhere to these
Do Not hammer directly on the fuel harness

precautions could lead to serious personal Injury.
body clips when installing new fuel pipes.
Damage to the nylon pipes may result In a
Safety Glasses and Compressed
fuel leak. Air Caution
Always cover nylon vapor pipes with a wet

Caution: Wear safety glasses when using
towel before using a torch near them. Also, compressed air in order to prevent eye Injury.
never expose the vehicle to temperatures
higher than 115C (239F) for more than one Safety Goggles and Fuel Caution
hour, or more than 90C (194F) for any Caution: Always wear safety goggles when
extended period. working with fuel In order to protect the eyes
Apply a few drops of clean engine oil to the

from fuel splash.
male pipe ends before connecting fuel pipe
fittings. This will ensure proper reconnectlon Vehicle Lifting Caution
and prevent a possible fuel leak. (During Caution: To help avoid personal Injury, when a
normal operation, the 0-rings located In the vehicle Is on a hoist, provide additional support
female connector will swell and may prevent for the vehicle at the opposite end from which
proper reconnectlon if not lubricated.) you are removing components. The additional
Fuel Gauge Leak Caution support will reduce the possibility of the vehicle
falling off the hoist. When you are removing
Caution: Wrap a shop towel around the fuel major components from the vehicle while the
pressure connection in order to reduce the risk of vehicle Is on a hoist, chain the vehicle frame to
fire and personal Injury. The towel will absorb any the hoist pads at the same end from which you
fuel leakage that occurs during the connection of are removing the major components to prevent
the fuel pressure gauge. Place the towel In an tip-off. If you fail to follow these precautionary
approved container when the connection of the measures, vehicle damage, serious personal
fuel pressure gauge is complete. Injury, or death may result.
Fuel Pipe Fitting Caution Window Removal Caution

Caution: Always apply few drops of clean
a Caution: When working with any type of glass,
engine oil to the male pipe ends before use approved safety glasses and gloves to
connecting fuel pipe fittings In order to reduce reduce the chance of personal injury.
the risk of fire and personal Injury.
This will ensure proper reconnectlon and prevent
a possible fuel leak.
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MD-lsuzu
Preface Cautions and Notices - 5
Work Stall Test Caution Handling ESD Sensitive Parts Notice

Caution: One or more of the following guidelines Notice: Electrostatic discharge (ESD) can damage
may apply when performing specific required many solid-state electrical components. ESD
tests in the work stall: susceptible components may or may not be labeled

When a test requires spinning the drive with the ESD symbol. Handle all electrical
wheels with the vehicle jacked up, adhere to components carefully. Use the following precautions
the following precautions: in order to avoid ESD damage:
Do not exceed 56 km/h (35 mph) when

-
Touch a metal ground point in order to remove
spinning one drive wheel with the other your body's static charge before servicing any
drive wheel stopped. This limit is necessary electronic component; especially after sliding across
because the speedometer indicates only the vehicle seat.
one-half the actual vehicle speed under
Do not touch exposed terminals. Terminals may
these conditions. Personal injury may result
connect to circuits susceptible the ESD damage.
from excessive wheel spinning.
If all of the drive wheels are spinning at
-
Do not allow tools to contact exposed terminals
the same speed, do not exceed 112 km/h when servicing connectors.
(70 mph). Personal injury may result from Do not remove components from their protective
excessive wheel spinning. packaging until required to do so.
All persons should stay clear of the
-
Avoid the following actions unless required by the

rotating components and the balance diagnostic procedure:
weight areas in order to avoid possible
personal Injury. Jumpering or grounding of the components
or connectors.
When running an engine in the repair stall
-
for an extended period of time, use care Connecting test equipment probes to components or
not to overheat the engine and the connectors. Connect the ground lead first when
transmission. using test probes.

When a test requires jacking up the vehicle Ground the protective packaging of any component
and running with the wheels and brake before opening. Do not rest solid-state components
rotors removed, adhere to the following on metal workbenches, or on top of TVs, radios, or
precautions: other electrical devices.
Do not apply the brake with the brake
-
rotors removed. Ignition OFF When Disconnecting

Do not place the transmission in PARK
-
Battery Notice
with the drive wheels still spinning.
Notice: Always turn the ignition OFF when
Turn Off the Ignition in order to stop the
-
connecting or disconnecting battery cables, battery

powertrain components from spinning.
chargers, or jumper cables. Failing to do so may
damage the Powertrain Control Module (PCM) or
Defective Scan Tool Notice
other electronic components.
Notice: Do not use a scan tool that displays faulty
data. Report the scan tool problem to the Nylon Fuel Lines Notice
manufacturer. Use of a faulty scan tool can result in
misdiagnosis and unnecessary parts replacement. Notice: Do not attempt to straighten the kinked nylon
fuel lines. Replace any kinked nylon fuel feed or return
pipes in order to prevent damage to the vehicle.
Fastener Notice
Notice: Use the correct fastener in the correct PCM and ESD Notice
location. Replacement fasteners must be the correct
part number for that application. Fasteners requiring Notice: Do not touch the connector pins or soldered
replacement or fasteners requiring the use of thread components on the circuit board in order to prevent
locking compound or sealant are identified in the possible electrostatic discharge (ESD) damage to
service procedure. Do not use paints, lubricants, or the PCM.
corrosion inhibitors on fasteners or fastener joint
surfaces unless specified. These coatings affect Single Cylinder Flooding Notice
fastener torque and joint clamping force and may
damage the fastener. Use the correct tightening Notice: In order to prevent flooding of a single
sequence and specifications when installing fasteners cylinder and possible engine damage, relieve the
in order to avoid damage to parts and systems. fuel pressure before performing the fuel injector
coil test procedure.
Fuel Pressure Notice
Notice: Do not allow the fuel pressure to exceed the
specified value because damage to the fuel pressure
regulator or the fuel pressure gauge may result.
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Section 0
General Information
General Information..........................................o-3 Maintenance ......................................................0-35

Conversion -
Maintenance Schedule...................................0-35
English/Metric.............................0-3
Equivalents Decimal and Metric
-
Maintenance Schedule Short Trip/City.......0-43
-
...................0-3
Paper Version of the Service Manual -
Maintenance Schedule -
How to Use..................................................0-4 Long Trip/Highway

.....................................0-43
Arrows and Symbols........................................0-5 Owner Checks and Services (General)........0-43
Special Tools Ordering Information Owner Checks and Services (Single Axle)...0-46
.................0-5
Vehicle Identification.........................................0-5 Explanation of Scheduled Services...............0-47
VIN Inspections and Other Services
Derivative...................................................0-6 ....................0-50
Label Vehicle Certification.............................0-7
-
Vibration Diagnosis and Correction.........0-51
Engine Identification.........................................0-8 Specifications....................................................0-51
Transmission Identification Specifications..................................................0-51
...............................0-8
Rear Axle Identification....................................0-9 Diagnostic Information and Procedures .......0-52
Label Service
-
Parts Systematic Approach .....................................0-52
ID................................0-11
RPO Code Vibration Diagnosis
List...............................................0-11 ........................................0-52
Labels How to Obtain Replacement...........0-17
-
Road
Test.......................................................0-52
Fasteners (Prevailing Torque Fasteners)......0-17 Classifying the Vibration
................................0-56
Fasteners (Strength Identification).................0-19 Tire and Wheel Vibration...............................0-59
Fasteners (Metric Fasteners).........................0-20 Tire and Wheel Runout Measurement..........0-59
Thread Inserts................................................0-20 Driveline Vibration Analysis with EVA...........0-63
Torque Wrenches ...........................................0-21 Engine Related Vibration...............................0-67
Abbreviations and Their Meanings................0-23 Repair Instructions...........................................0-71
Key and Lock Cylinder Coding......................0-26 General Service Precautions.........................0-71
Lifting and Jacking the Correcting Tire and Wheel Vibration.............0-71
Vehicle......................0-26
Cab Balancing Tires and
Tilting......................................................0-27 Wheels..........................0-71
Towing a Disabled Wheel Weight Usage.....................................0-75
Vehicle.............................0-30
Strategy Based Correcting Non-Uniform
Diagnosis..............................0-32 Tires........................0-75
Maintenance and Lubrication......................o-33 Correcting Driveline Vibration -
RWD and
Specifications....................................................0-33 4WD..........................................0-76
Approximate Fluid Capacities........................0-33
Description and Operation..............................0-94
Fluid and Lubricant Recommendations......... 0-34 General Description........................................0-94
Special Tools and Equipment. .0-105
Maintenance Items .........................................0-34
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0-2 Table of Contents General Information
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General Information General Information 0-3
General Information
Conversion -
English/Metric (cont'd)
In order to convert English units to metric units,
Multiply/
multiply the English units by the conversion factor
English Divide by Metric
shown in the conversion table.
In order to convert metric units to English units, PRESSURE (STRESS)
divide the metric units by the conversion factor inches of Mercury 3.377 RPa
shown in the conversion table. inches of H20 0.2491
kPa
Ib/sq in 6.895
Conversion -
English/Metric
LIGHT
Multiply/
Foot Candle 10.764 lm/m2
English Divide by Metric
VELOCITY
LENGTH
mph 1.6093 km/h
in 25.4 mm
TEMPERATURE
ft 0.3048
m F 5/9(-F-32) C
yd 0.9144
C 9/5('C+32) F
mi 1.609 km
FUEL PERFORMANCE
AREA
mpg 2.3527 L/km
645.2 sq mm
sq in
6.45 sq cm
Refer to the following table for equivalent of
sq ft 0,0929
sq m fractions to decimals in English (inches), to
sq yd 0.8361 metric (millimeters).
VOLUME
16,387.0 cu mm Equivalents
Decimal and Metric
cu in 16.397 cu cm Fraction (in) Decimal (in) Metric (mm)
0.0164 1/64 0.015625 0.39688
qt 0.9464 L 1/32 0.03125 0.79375
gal 3.7854 3/64 0.046875 1.19062
cu yd 0.7646 cu m 1/16 0.0625 1.5875

MASS 5/64 0.078125 1.98437
Ib 0.4536 3/32 0.09375 2.38125
kg
907.18 7/64 0.109375 2.77812
ton
0.907 tonne (t) 1/8 0.125 3.175
FORCE 9/64 0.140625 3.57187
kg 9.807 5/32 0.15625 3.96875
oz 0.2780 newtons (N) 11/64 0.171875 4.36562
Ib 4.448 3/16 0.1875 4.7625
ACCELERATION 13/64 0.203125 5.15937
ft/s2 0.3048 7/32 0.21875 5.55625
m/s2
in/s2 0.0254 15/64 0.234375 5.95312
TORQUE 1/4 0.25 6.35

Ib in 0.11298 17/64 0.265625 6.74687
N.m
Ibft 1.3558 9/32 0,28125 7.14375
POWER 19/64 0.296875 7.54062
hp 0.746 kW 5/16 0.3125 7.9375

21/64 0.328125 8.33437
1998 -
MD-ISUZU
0-4 General Information General Information
Equivalents -
Decimal and Metric (cont'd) Paper Version of the Service Manual -
Fraction (in) Decimal (in) Metric (mm) How to Use

11/32 0.34375 8.73125 Construction
This service manual is constructed with the following
23/64 0.359375 9.12812 10 major sections:
3/8 0.375 9.525
25/64 0.390625 9.92187 Major Section
13/32 0.40625 10.31875 Number Major Section Name
0 General Information
27/64 0.421875 10.71562
7/16 0.4375 11.1125 1
Heating, Ventilation, and
Air Conditioning (HVAC)
29/64 0.453125 11.50937
2 Steering
15/32 0.46875 11.90625
3 Suspension
31/64 0.484375 12.30312
4 Driveline/Axle
1/2 0.5 12.7
5 Brakes
33/64 0.515625 13.09687
6 Engine
17/32 0.53125 13.49375
7 Transmission/Transaxle
35/64 0.546875 13.89062
8 Chassis/Body Electrical
9/16 0.5625 14.2875
9 Accessories
37/64 0.578125 14.68437
10 Body
19/32 0.59375 15.08125
39/64 0.609375 15.47812
Information Flow
5/8 0.625 15.875
Each major section will be structured as follows:
41/64 0.640625 16.27187
1. A single table of contents for the entire major
21/32 0.65625 16.66875 section; including all contents of the
43/64 0.671875 17.06562 subsections within the major section.
11/16 0.6875 17.4625 2. Subsections
45/64 0.703125 17.85937 The service information located within each
23/32 subsection will be ordered as follows:
0.71875 18.25625
1. Specifications
47/64 0.734375 18.65312
3/4 0.75 19.05 2. Diagnosis
49/64 0.765625 19.44687 3. Repair procedures

25/32 0.78125 19.84375 4. General description and system operation
51/64 0.796875 20.24062 5. Special tools
13/16 0.8125 20.6375
Improvements Made
53/64 0.828125 21.03437 This service manual provides many more illustrations
27/32 0.84375 21.43125 than in earlier manuals. Illustrations serve as the
55/64 0.859375 21.82812 primary source for repair procedures. These
illustrations will be supplemented with text
7/8 0.875 22,225
descriptions. In the previous service manuals, text
57/64 0.890625 22.62187 was the primary source of information for repair
29/32 0.90625 23.01875 procedures and illustrations provided support.
59/64 0.921875 23.41562 Repair procedures, illustrations, and the descriptive
15/16 text have been arranged so that they will correspond
0.9375 23.8125
with the way you work. This manual provides
61/64 0.953125 24.20937 disassembled views, wherever possible, so that it will
31/32 0.96875 24.60625 be easy to look up parts, names, and order of
63/64 0.984375 25.00312 assembly. The text descriptions have been rewritten
into simple, complete sentences.
1 1.0 25.4
1998 -
MD-lsuzu
Arrows and Symbols Special Tools Ordering Information
Special Tools
The special service tools shown in this service
manual have tool product numbers beginning with
J or BT. Special tools are distributed worldwide by
^^^ Kent-Moore:
Kent-Moore
^^^^ SPX Corporation
29784 Little Mack
4 Roseville, Ml 48066-2298
5 1-800-328-6657
0 ^ Mon.-Fri. 8:00 a.m. to 7:00 p.m. EST

Telex: 244040 KMTR UR
Fax: 1-800-578-7375
Purchase scan tools and accessories from
Kent-Moore at the address above.
Vehicle Identification
y> \^,
11
\.12
>- ^
196216
Legend
(1) Front of Vehicle
(2) View Detail
(3) Ambient Air Mixed With Another Gas, Can
Indicate Temperature Change
(4) Motion or Direction
205884
(5) View Angle
(6) Dimension (1:2) The Isuzu Commercial Truck is available in the
above body style.
(7) Ambient/Clean Air Flow, Cool Air Flow
(8) Lubrication PointOil or Fluid*
(9) Task Related
(10) Sectioning (1:3)
(11) Gas Other Than Ambient Air, Hot Air Flow
(12) Lubrication PointGrease or Jelly*
1998 -
MD-lsuzu
VIN Derivative
The Vehicle Identification Number (VIN) is the legal
identifier of the vehicle. The VIN contains the
following information:
The manufacturer
The model
The chassis type
The engine type
The Gross Vehicle Weight (GVW) range
The model year
The plant code
The sequential number
205886
The VIN plate is attached to the driver's door

opening.
Vehicle Identification Number (VIN) System

Position Definition Character Description
1 Country of Origin 4 United States
2 Manufacturer G Isuzu
3 Model T Isuzu Incomplete Vehicle
A 9001-10000 Hydraulic
B 10001-14000 Hydraulic
C 14001-16000 Hydraulic
D 14001-16000 Air
E 16001-19500 Hydraulic
F 16001-19500 Air
G 19501-23500 Hydraulic
H 19501-23500 Air
J 23501-26000 Hydraulic
4 GVWR/Brake System K 23501-26000 Air
L 26001-33000 Hydraulic
M 26001-33000 Air
N 33001-40500 Hydraulic
P 33001-40500 Air
R 40501-48500 Hydraulic
S 40501-48500 Air
T 48501-58000 Air
V 58001-69500 Air
W 69501-over Air
6 6000
5 Series
7 7000
6 Cab Type C Medium Tilt, Steel, 226 cm (89") BBC
7 Chassis Type 1 4 x 2, 2 Axles, 1 Driving
8 Engine Type 2 Isuzu 6 Cylinder Turbo Diesel (7.8L)
1998 -
MD-lsuzu
Vehicle Identification Number (VIN) System (cont'd)
Position Definition Character Description
9 Check Digit 1
10 Model Year
1998
11 Plant Location J Janesville
12-17 Plant Sequence Number

6-Digit Sequential Numbers
Label -
Vehicle Certification The Gross Vehicle Weight (GVW) is the weight of
the stock vehicle and all the options added to the
Complete Vehicle Certification Label vehicle after leaving the factory. The GVW includes,
but not limted to, the weight of the following items:
The body

Winches

Booms
The driver
QVW RATINQ INFORMATION All occupants
OWR-LB/KQ QAWR FBT OAWR INT QAWB RB

The load that the vehicle is carrying
TIRE SIZE PSI/KPA (COLD) Ensure that the Gross Vehicle Weight (GVW) does
not exceed the Gross Vehicle Weight Rating
ASSEMBLED IN JANESVILLE Wl (GVWR). Ensure that the front and the rear Gross
^ L^
SEE OWNER'S MANUAL FOR ADDITIONAL INFORMATION II
Axle Weights (GAW) do not exceed the front and the
rear Gross Axle Weight Rating (GAWR).
291017
Incomplete Vehicle Certification Label
6VWR-IB/KQ QAWR FRT QAWB INT OAWH RR
TIRE SIZE
205890
The payload rating shown on the label is the

maximum allowable cargo load (including the weight
of the driver and all occupants) that the vehicle may
carry based on the stock equipment. The payload
rating lowers if any accessories or other equipment
are added to the vehicle after the final date of
291007
manufacture. Determine the weight of any added
The Vehicle Certification Label indicates the following accessories and deduct the amount from the
ratings for the vehicle: payload rating.
. The Gross Vehicle Weight Rating (GVWR) The vehicle may also have a Gross Combination
The front and rear Gross Axle Weight Weight Rating (GCWR). The GCWR is the total
weight of the loaded tow vehicle (including
Rating (GAWR)
passengers) and a loaded trailer.

The payload rating
7998 -
MD-lsuzu
Ensure that the tires on the vehicle are the proper Allison
size and at the proper inflation pressure for the load
that the vehicle is carrying. The vehicle certification
label shows the stock tire size and recommended
inflation pressures.
Engine Identification
Diesel Engine
The engine serial number is located on the front
right side comer of the engine block.
Transmission Identification
Isuzu
208521
The Allison transmission identification plate is

located on the rear left side of the housing, just
above the oil pan.
208509
The Isuzu transmission identification plate is located

on the left upper side of the housing.
Eaton Fuller _
Transmissions
F^RT-'^ "^
200589
1998 -
MD-lsuzu
Rear Axle Identification

Eaton Rear Axle ID
200579
Legend
(1) Axle Specification Number (4) Capacity
(2) Casting Number (5) Housing Subassembly Number (Including
(3) Rough Number Tubes)
All axle housings have identification tags or

identification information stamped on the side of the
differential carrier.
Differential Carrier
The carrier tag may contain the following information:
The axle model

The ratio
The carrier assembly number
The carrier serial number

The date of assembly
Use all the information on the carrier tag in order to
identify the axle assembly.
1998 -
MD-lsuzu
Eaton Differential Carrier ID
200584
Legend
(1) Side View
(2) Top View
Dana/Spicer Rear Axle Differential Carrier ID Axle Housing
Dana/Spicer Rear Axle ID
200587
200582
Legend
(1) Dana Part Number Legend
(2) Customer Part Number (Optional) (1) Dana Part Number
(3) Julian Date Code (2) Customer Part Number (Optional)
(4) Line Set Number (Optional) (3) Model
(5) Last Six Digits of Vehicle Serial Number (4) Julian Date Code
(Optional) (5) Line Set Number (Optional)
(6) Last Six Digits of Vehicle Serial Number
(Optional)
The housing tag is the same type of tag used for

the Differential Carrier.
1998 -
MD-lsuzu
Label -
Service Parts ID RPO Code List
RPO Description
Seat: Front Bucket, Driver High Back,
ASA
Self Contained Air Suspension
Seat: Center Front Bucket, Auxiliary,
AV8 Folding
BAG Parts Package Export

First Position Prop Hanger, NON-BOC,
BPU
Height A
BPV
Height B

BPW
Height C

BUB
Height D
BUC
Height E
205849
CKD Vehicle Completely Knocked Down
The Service Parts Identification Label is on the
CV3 Country Mexico
passenger's side sun visor.
HVAC System Air Conditioner, Front
C60
Manual Controls
mnn h
u.t.A. Mirror: Outside, LH and RH,
DFO
SERVICE PARTS IDENTIFICATION 17.8 cm x 40.6 cm (7 in x 16 in), SST
WIGDI iHpasia i
.|.N. v.hlcl. KHnUlteolta Niinr Mirror: Outside, Dual Velvac Heated,
HOTT: Th opHonot )ufpmnl lttd blow hu bn IrrloaKlan thh hiel*. lorprflf
MxnIMcaMon 1 fploeflnrnt parti b w ! pMlfy th oppflcabi* opKon numbw. DNN 15.2 cm x 40.6 cm (6 in x 16 in),
OP-ID,* OPTION
aescmpnoN ocscmpTtOf* Stainless Steel
Mirror: Auxiliary Outside 20 cm (8 in)
DTE
Spot, Dual Retrac, SST
EG5 401 cm (158 in) Wheelbase
EH8 432 cm (170 in) Wheelbase

EK8 478 cm (188 in) Wheelbase
EM2 508 cm (200 in) Wheelbase
EQ8 592 cm (233 in) Wheelbase
IMPORTANT ".i.ii..i.b...,.p.,m...,,,.ci . ERA Second Position Prop Hanger, Height A
ERB Second Position Prop Hanger, Height B
ERC Second Position Prop Hanger, Height C
200611
ERD Second Position Prop Hanger, Height D
Always refer to the Service Parts Identification Label ERE Second Position Prop Hanger, Height E
when ordering parts. The label lists the following
items: ESS 630 cm (248 in) Wheelbase
The Vehicle Identification Number (VIN) EV9 Suspension: Attach Bolted

The wheelbase EXP Export I.E.S.

The paint information EY1 Yoke: Propeller Shaft, Driveline, Dana
All production options Frame: Rail, Full Depth,

FDO 612 cm x 15 cm (241 in x 6 in),
All factory-installed special equipment
22 680 kg (50,000 Ib)
Frame: Rail, Full Depth,

FD5 622 cm x 20 cm (245 in x 8 in),
36 288 kg (80,000 Ib)
FF1 Hub: Front, Oil Filled
1998 -
MD-lsuzu
RPO Code List (cont'd) RPO Code List (cont'd)

RPO Description RPO Description
Suspension: Front, Multileaf, 4 090 kg Suspension: Rear, Tapered Leaf,
FK9 GR9
(9,017 Ib) 9 525 kg (21,000 Ib)
FL1 Axle: Front, 3 674 kg (8,100 Ib) GZI GVW Rating: 11 771 kg (25,950 Ib)
FL2 Axle: Front, 4 990 kg (11,000 Ib) Provisions for Taperleaf/Multileaf Rear
GZT
Springs
FL3 Axle: Front, 6 623 kg (14,600 Ib)
Suspension: Rear Air, 8 618 kg
Suspension: Front, Multileaf, 6 610 kg G40
FMO (19,000 Ib)
(14,600 Ib)
G60 Spring: Rear, Auxiliary
Suspension: Front, Multileaf, 6 350 kg
FM4
(14,000 Ib) G68 Shock Absorbers: Rear, Heavy Duty
FPL 554 cm (218 in) Wheelbase G86 Axle: Limited Slip
FQT 356 cm (140 in) Wheelbase G98 Seal: Rear Axle Oil, Stemco
FS7 Axle: Front, 5 443 kg (12,000 Ib) HD Axle: Rear, Eaton 23105S, Single
HNA
Speed, 10 433 kg (23,000 Ib)
Frame: Rail, Full Depth,
F03 232 cm x 25 cm (249 in x 10 in), Axle: Rear, Eaton 22060S, Single
HPG
49,896kg (110,000 Ib) Speed, 9 979 kg (22,000 Ib)
Reinforcement: Frame, Outside, Axle: Rear, Eaton 22060T, Two
F08 HPH
Inverted L Type, 36,288 kg (80,000 Ib) Speed, 9 979 kg (22,000 Ib)
Suspension: Front, Tapered Leaf, Axle: Rear, Eaton 19060S, Single
F12 HPK
3 175 kg (7,000 Ib) Speed, 8618kg (19,000 Ib)
Suspension: Front, Tapered Leaf, Axle: Rear, Eaton 19060T, Two
F14 HPM
3674kg (8,100 Ib) Speed, 8618kg (19,000 Ib)
Suspension: Front, Tapered Leaf, Axle: Rear, Eaton 21060S, Single
F15 HPP
4 082 kg (9,000 Ib) Speed, 9526kg (21,000lb)
Suspension: Front, Tapered Leaf, Axle: Rear, Eaton 23080S, Two
F26 HPQ
5 443 kg (12,000 Ib) Speed, 10 433 kg (23,000 Ib)
F59 Stabilizer Shaft: Front Control: Rear Axle Shift, Two Speed,
HPZ
Electric
Suspension: Rear, Multileaf, 6 804 kg
GGO
(15,000 Ib) Axle: Rear, Eaton 19050S, Single
HWY
Suspension: Rear, Tapered Leaf Speed, 7666kg (16,900 Ib)
GG7
7 666 kg (16,900 Ib) Axle: Rear, Eaton 19050T, Two
HZT
Suspension: Rear, Tapered Leaf, Speed, 8097kg (17,850 Ib)
GNO
8 620 kg (19,000 Ib) Axle: Rear, Eaton 19050S, Single
HZW
GN1 Stabilizer Shaft: RR (Dup with F61) Speed, 8097kg (17,850 Ib)
Axle: Rear, Dana S150-S, Single
Suspension: Rear, Multileaf, 8 620 kg H08
GN2 Speed, 6 804 kg (15,000 Ib)
(19,000 Ib)
Axle: Rear, Eaton 15040S, Single
Suspension: Rear, Multileaf, 9 525 kg H10
GN8 Speed, 6 804 kg (15,000 Ib)
(21,000lb)
GPG Axle: Rear, Eaton 19050S, Single
Vehicle: Low Profile Package H11
Speed, 8618kg (19,000 Ib)
Suspension: Rear, Tapered Leaf,
GPO Axle: Rear, Eaton 21060T, Two
10 430 kg (23,000 Ib) H15
Speed, 9526kg (21,000lb)
Suspension: Rear, Multileaf, 10 660 kg
GP1 Axle: Rear, Eaton 23080T, Two
(23,500 Ib) H20
Speed, 10 433 kg (23,000 Ib)
GQB Third Position Prop Hanger, Height A
JE3 Brake: Hydraulic
GQC Third Position Prop Hanger, Height B
JE4 Brake: Air
GQD Third Position Prop Hanger, Height C
Braking System, Power, Antilock, Front
GQE Third Position Prop Hanger, Height D JE5
and Wheel
GQF Third Position Prop Hanger, Height E Brake Rating: Rear, Air Carlisle,
Suspension: Rear, Tapered Leaf, NAB9ML, Non-Abestos Lining, 14cm
GQO JPV
8 600 kg (15,000 Ib) (5.5 in) Slack, 42 cm x 178 cm (16.5 in
x 7 in) Fab Shoe, 16 Hole Mounting
7998 -
MD-lsuzu
JPZ Valve: Air Suspension, Air Release JYV Brake Provisions: Full Trailer
Universal Joint: Main, 1480/148N JZC Chamber: Front Brake, Type 16
JOB
Series
JZD Chamber: Front Brake, Type 20
Adjuster: Rear Slack, Automatic,
JQF JZE Chamber: Front Brake, Type 24
Rockwell
JZF Chamber: Rear Brake, Type 30
JQM Universal Joint: Main, 1710/17N Series
JZG Chamber: Rear Brake, Type 24
Universal Joint: Main, 1550/155N
JQP J71 Parking Brake: Power Operated
Series
Universal Joint: Main, 1710/17N Series, J78 Valve: Moisture Ejector Air Brake
JQQ
HD Tube J91 Brake Provisions: Trailer
Universal Joint: Main, KG8 Generator: 130 AMP
JQR
1610/161 N Series
KRW Hose: Radiator, Silicone
Universal Joint: Inter Axle,
JRA KVB Hose: Water, Silicone, Except Radiator
1610/161 N Series
Air Compressor: Zexel, 185L/MN, Water
Brake Rating: Front, Air Carlisle, E145A KYC
Cooled
JRD Non-Abestos Lining, 14 cm (5.5 in)
Slack, 4 or 8 Hole Mounting K40 Engine Brake: Exhaust
JRF Shield: Rear Brakes, Dust K60 Generator: 100 AMP
Brake Rating: Rear, Air Carlisle, E145A LG4 Engine: Diesel, 6 Cylinder, 7.8L, Turbo
Non-Abestos Lining, 14 cm (5.5 in) Engine: Diesel, 6 Cylinder, 7.8L,
JRL LQB
Slack, 42 cm 18 cm (16.5 in x 7 in) Fab 149 kW (200 Gross hr), 2400 RPM
Shoe, 10 Hole Mounting Engine: Diesel, 6 Cylinder, 7.8L,
LQC
Brake Rating: Rear, Air Carlisle, E145A 172 kW (230 Gross tip), 2400 RPM
Non-Abestos Lining, 15 cm (6 in) Slack,
JRN Transmission: Allison AT545,
42 cm x 18 cm (16.5 in x 7 in) Fab MF1
Automatic
Shoe, 9 Hole Mounting
Transmission Manual 5-speed Fuller
Brake Adjuster, RR Slack, Eaton MPU
JTJ FS5005A
Automatic
Clutch: 350 mm, (13.8 in) Single Plate,
Brake Adjuster, Front Slack, Eaton MRK
JTK Push Type, Dana-Spicer
Automatic
Pilot Shaft: Automatic Transmission,
Air Dryer B/W Model, AD9 Heated, MWE
JTT No Spline
Brake Air Tank
Pilot Shaft: Automatic Electric
Brake Adjuster: Front Slack, Rockwell MWF
JUE Transmission, No Spline
Automatic
Clutch Spicer 14-1 Cerametallix, Pull
Equipment RR Brake Chamber Brand, MWM
JUZ Type, Greasable Bearing
MGM E-Series
Pilot Shaft: Transmission, 44.45 mm
JVA Provisions Antilock Brake Delete MWW
(1.75 in) Spline
Brake Rating: Front, Air Carlisle, E145A
Pilot Shaft: Transmission, 38.1 mm
Non-Abestos Lining, 14 cm (5.5 in) MWX
JVQ (1.5 in) Spline
Slack, 42 cm x 13 cm (16.5 in x 5 in)
Fab Brake Shoe, 8 Hole Mounting Transmission: Manual, 6 Speed,
M54 ISUZU, 136 mm (5.35 in), 6.72 1st,
Brake Rating: Rear, Air Carlisle, E145A
Over Drive
Non-Abestos Lining, 14 cm (5.5 in)
JWB
Slack, 42 cm x 18 cm (16.5 in x 7 in) NB5 Exhaust System: Single
Fab Brake Shoe, 16 Hole Mounting Fuel Tank: 189L, (50 gal), LH,
NLO
Brake Rating: Rear, Air Carlisle, E145A Rectagular, Steel
Non-Abestos Lining, 15 cm (6 in) Slack, Fuel Tank: 189L, (50 gal), Dual,
JWF NL5
42 cm x 18 cm (16.5 in x 7 in) Fab Rectangular, Steel
Shoe, 16 Hole Mounting
NXN Fuel: 57L (15 gal) Additional
Universal Joint: Main, 1750/176N
JXD NXY Steering: Power, ZF
Series, HD Tube
Wheel: Polished Aluminum,
Valve: Air Brake Moisture Ejector, B/W PNB
JXG Both Sides, Rear
DV2, Heated, Front
1998 -
MD-lsuzu

PNL Secondary Color: Exterior, Penske Wheel: Rear, 22.5x8.25, 10 Hole,
RPR
PNQ Angle: Rear Axle Pinion, Nominal 3" 285.75 mm (11.25 in), BC, Piloted Hub
Wheel: Rear, 19.5 x 6.75, 8 Hole,
PNR Angle: Rear Axle Pinion, Nominal 4' RPW
275 mm (10.8 in), BC, FN, Piloted Hub
PNS Angle: Rear Axle Pinion, Nominal 5"
RQ2 Vehicle Application: Truck Service
PNU Primary Color: Interior, Penske
Front Tire: Extra Strength Highway
PNX Angle: Rear Axle Pinion, Nominal 6" R3B
Tread
PNY Angle: Rear Axle Pinion, Nominal 7' R3C Front Tire: Premium Highway Tread
Wheel: Front Generic, 8 Hole, 275 mm R3M Front Tire: All Season Tread
PQR
(10.8 in), BC, FN
Front Tire: Premium Highway Improved
Wheel: Rear Generic, 8 Hole Disc, R3N
PQS Steering Control Tread
275mm (10.8 in), BC, FN
R4A Front Tire Brand: Goodyear
Wheel: Front, Generic Steel, 10 Hole,
R4H Front Tire Brand: General
PQU 285.75 mm (11.25 in), BC, Disc
Piloted, Disc R4L Front Tire Brand: Michelin
Wheel: Rear, Generic Steel, 10 Hole, R4N Front Tire Brand: Bridgestone
PQV 285.75 mm (11.25 in), BC, Disc R4R Front Tire Brand: Select, Brand Plant
Piloted, Disc
R4T Front Tire Brand: Yokohama
Wheel: Front, Generic Steel, 10 Hole,
PQY R6B Control Sales Item No. 02
287.75 mm (11.25 in), BC, Piloted
R6G Control Sales Item No. 07
Wheel: Rear, Generic Steel, 10 Hole,
PQZ
287.75 mm (11.25 in), BC, Piloted R6P Control Sales Item No. 15
PRS Identification Pro-Spec R9U Control Sales Item No. 95
PTA Provisions Low Profile Front Tires SGB Form Advanced Broadcast Document
Wheel: Front, Generic 8 Hole, 275 mm Spacer Pack: Right Spring Cab
PVG SMA
(10.8 in), BC Leveling, +10 mm (+.374 in)
Wheel: Rear, Generic 8 Hole, 275 mm Spacer Pack: Right Spring Cab
PVH SMB
(10.8 in), BC Leveling, +0 mm (+0 in)
P2C Pricing Wheels, Class A Spacer Pack: Right Spring Cab
SMC
Tire Tread, Spare Tread and Brand, Leveling, -10 mm (-.374 in)
P53
Front Match Spacer Pack: Right Spring Cab
SMD
Tire Tread, Spare Tread and Brand, Leveling, -20 mm (-.787 in)
P54
Rear Match SNF Wheel: Front, Spare
QE5 Odometer Rear Axle Hub SNR Wheel: Rear, Spare
Wheel: Front, 22.5 x 7.50, 10 Hole, Tire Tread: Rear, Extra Strength
S3B
QH3 287.75 mm (11.25 in) BC, FN, Hub Highway
Piloted
S3C Tire Tread: Rear, Premium Highway
Wheel: Rear, 22.5 x 7.50, 10 Hole,
S3D Tire Tread: Rear, Highway Premium
QH4 287.75 mm (11.25 in) BC, FN, Hub
Piloted S3E Tire Tread: Rear, On/Off Road Highway
Wheel: Front, 19.5 x 6.0, 8 Hole, S3F Tire Tread: Rear, Off Road Rolling
Q82
275mm (10.8 in), BC, FN S3H Tire Tread: Rear, Highway
Wheel: Rear, 19.5x6.0, 8 Hole, S3J Tire Tread: Rear, Highway Traction
Q83
275mm (10.8 in), BC, FN
S3K Tire Tread: Rear, On/Off Road Rib
Wheel: Front, 22.5 x 8.25, 10 Hole,
RNE S3L Tire Tread: Rear, Off Road Traction
285.75 mm (11.25 in), BC, Piloted Hub
S3M Tire Tread: Rear, All Season
Wheel: Rear, 22.5x8.25, 10 Hole,
RNF
285.75 mm (11.25 in), BC, Piloted Hub Tires: Tread, Rear, Premium Highway,
S3N
Wheel: Front, 19.5x6.75, 8 Hole, Improved Steering Control
RPM
275 mm (10.8 in), BC, FN, Piloted Hub S4A Rear Tire Brand: Goodyear
Wheel: Front, 22.5 x 8.25, 10 Hole, S4C Rear Tire Brand: Dunlop
RPQ
285.75 mm (11.25 in), BC, Piloted Hub
1998 -
MD-lsuzu
S4H Rear Tire Brand: General Tire: Front, 255/80R22.5/G, 14PR, BL
XSB
S4L TL Radial
Rear Tire Brand: Michelin
S4N Tire: Front, 275/80R24.5/G, 14PR, BL
Rear Tire Brand: Bridgestone XSH
TL Radial
S4R Rear Tire: Select, Brand Plant
Tire: Front 255/70R22.5/H, 16PR, BL
S4T Rear Tire Brand: Yokohama XTB
TL Radial
TMO Battery: 900 CCA, Dual
Tire: Front, 245/70R19.5/F, 12PR, BL
XTI
TNL Battery: Twin, 12V (1110) TL Radial
TNN Battery: Twin, Deico 1150, 12V Tire: Front, 225/70R19.5/F, BW, R/ST
XTN
TRF Tires: Front, Radial Identifier
TLHWY
Tire: Front, 245/75R22.5/G, BL TL
TRG Tire Selection, Customer Brand XTQ
Radial
TRH Tire Selection, Customer Brand
Tire: Front, 265/75R22.5/G, BL TL
XTU
TRR Tires: Rear, Radial Identifier Radial
TRZ Equipment Air Shift Transmission Tire: Front, 8.00R19.5/F, 12 PR, BLTL
XTX
T62 Lighting: Daytime Running Radial
UEA Taillamp Delete Tire: Front, 245/70R19.5/G, 14PR, BL

XTY
TL Radial
Indicator, Electronic Transmission,
UET Tire: Front, 10.00R22.5/F, 12PR, BLTL
Oil Level
XWJ
Radial
Radio: AM/FM Stereo, Seek & Scan,
UM6 Tire: Front, 10.00R22.5/G, 14PR, BLTL
Auto Reverse Cassette, Clock, ETR XWK
Radial
Radio: AM/FM Stereo, Seek & Scan,
UM7 Tire: Front, 11 .OOR22.5/G, 14PR, BLTL
Clock, ETR XWL
Radial
UZF Alarm B/U Electrical, 97 Decibles
Tire: Front, 11.00R22.5/H, 16PR, BLTL
U08 Horn: Dual Electric XWM
Radial
U86 Wiring Harness: Full Trailer, 7-Wire
X80 Plate GVW Rating
Vehicle Label, Noise Control
VCO Sales Package Body Override,
Information YA6
California
VC5 Label, Shipping, Except US, or Japan YES Vehicle Test, Engineering
Label, Shipping, Hawaii, US Territories,
VC6 YF5 Certification Emission, California
and Puerto Rico
Sales Processing Option Geographic
VH4 Mud Flaps YF6
Control, California
Cable: Trailer Jumper Cable, 7-Wire,
VPG Tire: Rear, 8.00R19.5/E, 10PR, BLTL
12-foot, Synflex Coiled YQT
Radial
VPH Vehicle Preparation Overseas Delivery
Tire: Rear, 235/80R22.5/G, 14PR, BL
YRL
VWN Hook: Tow, Rear, Bolt On TL Radial
VXT Vehicle Incomplete Tire: Rear, 295/75R22.5/G, 14PR, BL
YRN
V01 Radiator: Heavy Duty
TL Radial
V48 Coolant: Maximum Protection Engine YSB
TL Radial
V76 Hook: Tow
V78 Vehicle Statement: Delete YSH
TL Radial
V98 Vehicle Statement: Delete Tire: Rear, 255/70R22.5/H, 16PR, BL
YTB
WDB Control Engineering Edit TL Radial
Tire: Front, 8.00R19.5/E, 10PR, Tire: Rear, 245/70R19.5/F, 12PR, BLTL
XQT YTI
BL TL Radial Radial
Tire: Front, 235/80R22.5/G, 14PR, Tire: Rear, 225/70R19.5/F, BW, R/ST
XRL YTN
BL TL Radial ST TL HWY
Tire: Front, 295/75R22.5/G, 14PR, Tire: Rear, 245/75R22.5/G, BL TL
XRN YTQ
BL TL Radial Radial
7998 -
MD-lsuzu

Tire: Rear, 265/75R22.5/G, BL TL Tire: Spare, 10.00R22.5/F, 12PR, BL
YTU ZWJ
Radial TT Radial
Tire: Rear, 8.00R19.5/F, 12PR, BL TL Tire: Spare, 10.00R22.5/G, 14PR, BL
YTX ZWK
Radial TT Radial
Tire: Rear, 245/70R19.5/G, 14PR, BL Tire: Spare, 11.00R22.5/G, 14PR, BL
YTY ZWL
TL Radial TT Radial
Wheel: Single, Polished Aluminum, One Tire: Spare, 11.00R22.5/H, 16PR, BL
YU8 ZWM
Side, Front TL Radial
Tire: Rear, 10.00R22.5/F, 12PR, BL TL ZY1 Color Combination: Solid
YWJ
Radial ZY2 Color Combination: Two-Tone
Tire: Rear, 10.00R22.5/G, 14PR, BL TL Export Canadian Modified Mandatory
YWK Z49
Radial
Base Equipment
Tire: Rear, 11.00R22.5/G, 14PR, BL TL
YWL Z89 Conversion Name Plate ISUZU
Radial
001 3.70 Ratio Code
Tire: Rear, 11.00R22.5/H, 16PR, BL TL
YWM 002 4.11 Ratio Code
Radial
Attachment Main Driveline One-Shaft 003 4.33 Ratio Code

YX6
System 005 4.56 Ratio Code
Attachment Main Driveline Two-Shaft 006 4.63 Ratio Code
YX7
System
008 4.88 Ratio Code
Attachment Main Driveline Three-Shaft
YX8 009 5.29 Ratio Code
System
01 L Secondary Color: Exterior, Special
Attachment Main Driveline Four-Shaft
YX9 01U
System Primary Color: Exterior, Special
YY7 Paint Process Chassis 010 5.43 Ratio Code

YY9 Paint Process Wheel 011 5.57 Ratio Code
Tire: Spare, 8.00R19.5/E, 10 PR, BL 012 5.83 Ratio Code
ZQT
TL Radial 014 6.14 Ratio Code
Tire: Spare, 235/80R22.5/G, 14PR, BL 015 6.17 Ratio Code
ZRL
TL Radial
016 5.25 Ratio Code
Tire: Spare, 295/75R22.5/G, 14PR, BL
ZRN 017 6.50 Ratio Code
TL Radial
018 6.65 Ratio Code
Tire: Spare, 255/80R22.5/G, 14PR, BL
ZSB
Tire: Spare 275/80R22.5/G, 14PR, BL 020 5.63 Ratio Code
ZSH
Tire: Spare, 255/70R22.5/H, 16PR BL 032
ZTB 6.29 Ratio Code
TL Radial
038 6.57 Ratio Code
Tire: Spare, 245/70R19.5/F, 12PR BL
ZTI 039 3.55 Ratio Code
TL Radial
Tire: Spare, 225/70R19.5/F, BW, R/ST
057 3.36 Ratio Code
ZTN
ST TL HWY 066 4.10 Ratio Code
Tire: Spare, 245/75R22.5/F, BL TL 069 3.90 Ratio Code
ZTQ
Radial
070 5.38 Ratio Code
Tire: Spare, 265/75R22.5/G, BL TL
ZTU 092 4.30 Ratio Code
Radial
Primary Color: Exterior, White Kodiak,
Tire: Spare, 8.00/19.5/F, 12PR, BL TL 16L
ZTX Frost
Radial
Color: Primary Exterior, White Kodiak,
Tire: Spare, 245/70R19.5/G, 14PR BL 16U
ZTY Frost
TL Radial
23L Secondary Color: Exterior, Ocean Blue
ZV1 Statement of Origin Manufacture
23U Primary Color: Exterior, Ocean Blue
1998 -
MD-lsuzu
RPO Code List (cont'd) Fasteners (Prevailing Torque Fasteners)
RPO Description
Secondary Color: Exterior, Medium
24L
Blue Metallic
40P Wheel Color: White la}
41 P Wheel Color: Black
2 4 5
46L Secondary Color: Exterior, Dark Green
46U Primary Color: Exterior, Dark Green
5DO Paint Process Bumper, Light Gray
61L Secondary Color: Exterior, Tan
61 U Primary Color: Exterior, Tan
70L Secondary Color: Exterior, Dark Maple 9

71 L Secondary Color: Exterior, Red Orange
71 U Primary Color: Exterior, Red Orange
171892
72U Primary Color Exterior, Standard Red
Engineers design prevailing torque nuts in order to
Secondary Color: Exterior, Wheatland
86L develop an interference between the nut and bolt
Yellow
threads. Usually the interference is caused by
Primary Color: Exterior, Wheatland distorting the top of a metal nut (1,2) or by a nylon
86U
Yellow patch on the threads in the middle of the hex flat (3).
A nylon insert between the nut and bolt threads also
Secondary Color: Exterior, Tangier
88L
Orange may cause the interference (4,5).
88U Primary Color: Exterior, Tangier Orange Engineers design prevailing torque bolts in order to
develop an interference between the bolt and nut
threads, or the threads of a tapped hole. The
Labels -
How to Obtain Replacement interference is caused by distorting some of the
Order the following replacement labels through Isuzu threads using one of the following methods:
Service Parts: A nylon patch (8)

The Vehicle Emission Control Information
Adhesive (6)
(Exhaust Emission Tune-Up) A deformed thread profile (7)

The Spare Wheel Caution
An out of round thread area (9)

The Jacking
Recommendations for Reuse

The Spare Tire Storage
Perform the following steps in order to reuse clean,

The Belt Routing non-rusted, prevailing torque nuts:
The Engine Fan Caution
1. Clean dirt and other foreign material off of the

The Standard Parts Catalog lists the above labels nuts and bolts.
and other labels. The Vehicle Certification Label, the Inspect the nuts or bolts for the following
2.
Tire Pressure Placard, and the Service Parts conditions. If any of the following conditions
Identification Label are NOT available as exist, use a new prevailing torque fastener:
service parts. Cracks
. Rust

Damage
Elongation
Signs of abuse
Signs of overtightening
3. Assemble the parts.

4. Hand start the nuts or bolts.
5. Ensure that the fastener develops proper torque
before the fastener seats. Refer to the Torque
Table. If the proper torque does not develop,
use a new prevailing torque fastener.
6. Tighten the fastener to the torque specified in
the appropriate fastener tightening specification.
1998 -
MD-ISUZU
Metric Fasteners (Prevailing Torque)

Specification
Fastener Type Metric English
Nuts/Metal Bolts
6 0.4 N.m 4lbin
6.3 0.4 N.m 4lbin
8 0.8 N.m 7 Ib in
10 1.4 N.m 12 Ibin
12 2.2 N.m 19 Ib in
14 3.0 N.m 27 Ib in
16 4.2 N.m 37 Ib in
Adhesive or Nylon Coated Bolts

6 0.4 N.m 4lbin
6.3 0.4 N.m 4lbin
8 0.6 N.m 5 Ibin
10 1.2 N.m 11 Ibin
12 1.6 N.m 14 Ibin
14 2.4 N.m 21 Ib in
16 3.4 N.m 30 Ib in
English Fasteners (Prevailing Torque)

Specification
Fastener Type/Torque Units Metric English
Nuts/Metal Bolts
0.250 0.4 N.m 4lbin

0.312 0.6 N.m 5 Ibin
0.375 1.4 N.m 12 Ib in
0.437 1.8 N.m 16 Ib in
0.500 2.4 N.m 21 Ib in
0.562 3.2 N.m 28 Ib in
0.625 4.2 N.m 37 Ib in

Adhesive or Nylon Coated Bolts
0.250 0.4 N.m 4lbin

0.312 0.6 N.m 5 Ibin
0.375 1.0 N.m 9 Ibin
0.437 1.4 N.m 12 Ib in
0.500 1.8 N.m 16 Ib in
0.562 2.6 N.m 23 Ib in

0.625 3.4 N.m 30 Ib in
7998 -
MD-ISUZU
Fasteners (Strength Identification)
171891
Legend
(1) English Bolt, Grade 2 (Strength Class) (4) English Bolt, Grade 8 (Strength Class)
(2) English Bolt, Grade 5 (Strength Class) (5) Metric Nut, Strength Class 9
(3) English Bolt, Grade 7 (Strength Class) (6) Metric Bolts, Strength Class Increases as
Numbers Increase
Notice: The designation of the standard fasteners embossed on the bolt head for each strength grade
used on this vehicle are of coarse screw thread up above 2. That is, a bolt with one embossed line
to M8 and fine screw thread beyond M10. The indicates grade-3. Two embossed lines indicate
designation to pitch relations are somewhat different grade-4. Six embossed lines signify grade-8, the
between coarse screw thread and fine screw thread. highest-grade bolt (4).
Therefore, when replacing fasteners, the pitch should Correct replacement bolts and nuts are available
be confirmed carefully even if the replacement through American Isuzu Parts Distributor Network
fastener is the same metric fastener. (AIPDN). Many metric fasteners available in the
The most common metric fastener strength property after-market parts channels are designed to foreign
classes are 9.8 and 10.9. The class identification metric standards, and may have a different thread
number is embossed on the head of each bolt (6). pitch. Isuzu products use metric fasteners designed
Some metric nuts are marked with single digit to new, international standards. Some non-domestic
strength identification numbers on the nut face. bolt and nut suppliers may not yet use the
international standards.
English strength classes range from 2 (low strength)
to 8 (high strength). A grade-2 bolt has no lines
embossed on the bolt head (1). One radial line is
1998 -
MD-lsuzu
Fasteners (Strength Identification)

Metric Coarse Screw Threads Metric Fine Screw Threads
Thread Pitch Thread Pitch Thread Pitch Thread Pitch
M39 4 M8 1.25 M39x3 3 M20x1.5 1.5

M36 4 M7 1 M36x3 3 M18.1.5 1.5
M33 3.5 M6 1 M33x2 2 M16x1.5 1.5
M30 3.5 M5x0.8 0.8 M30x2 2 M14x1.5 1.5
M27 3 M4x0.7 0.75 M27x2 2 M12x1.25 1.25
M24 3 M4x0.7 0.7 M24x2 2 M 10x1.25 1.25
M22 2.5 M3.5 0.6 M22x1.5 1.5 M8x1 1
M20 2.5 M3x0.5 0.5
M18 2.5 M2.5 0.45
M16 2 M2.2 0.45 ~
M14 2 M2 0.4
M12 1.75 M1.6 0.35
M10 1.5
Fasteners (Metric Fasteners) Thread Inserts

Current model Isuzu vehicles are dimensioned
primarily in the metric system. Many fasteners are Repair Procedure
metric and are very close in dimension to fasteners Tools Required
in the inch system. Replace the fasteners using the General purpose thread repair kits. These kits are
following identical specifications: available commercially.
The nominal diameter Caution: Wear safety glasses in order to avoid
The thread pitch eye damage.
The strength
Most stock metric fasteners have numbers indicating
the strength of the material in the fastener. "Beauty"
bolts, such as exposed bumper bolts have no
strength indicator. Identify metric cross-recess screws
by a Posidriv or Type 1A marking. Use a Type 1A
cross-recess screwdriver in order to fasten or
unfasten metric cross-recess screws. If a Type 1A
cross-recess screwdriver is not available, use a
Phillips head screwdriver.
Isuzu Engineering Standards and other North
American industries use a portion of the standard
metric fastener sizes defined by the International
Standards Organization (ISO). Now the total number
of fastener sizes in use is lower, and the overall
strength quality of each thread size is higher.
For example, the metric M6.0 x 1 screw replaces the

English V4-20 and "1/4-28 screws, which have nearly
the same diameter. The thread pitch, 25.4 threads 4962
per inch, is between coarse and fine thread pitches
in English. Metric and English thread notations differ
Important: Refer to the thread repair kit
manufacturer's instructions regarding the size of the
slightly. The thread major diameter of a 1/4-20 bolt is
drill and tap to use.
1/4-inch, and the bolt has 20 threads per inch. The
thread major diameter of a 6.0 x 1 bolt is 6.0 mm, Avoid any buildup of chips. Back out the tap every
and the distance between threads is 1 mm. few turns and remove the chips.
1. Determine the size, the pitch, and the depth of

the damaged thread. If necessary, adjust the
stop collars on the cutting tool and tap to the
required depth.
1998 -
MD-lsuzu
2. Drill out the damaged threads. Clean out Torque Techniques

any chips. The frictional characteristics of each fastener or
3. Lubricate the tap with light engine oil. Tap the threaded hole can vary under a variety of
hole. Clean the threads. circumstances. For example, consider a joint that has
10 bolts. If all 10 fasteners were torqued to 20 N.m
and the clamp load is measured, all 10 bolts would
most likely have different clamp load readings. Even
though all 10 bolts are torqued at 20 N.m, it is not
guaranteed that they have all reached the same clamp
load. A rule of thumb is that the clamp load can vary
25 percent using torque control for joint assembly
At times, critical applications such as cylinder head
bolts require very tight tolerances for clamp load
distribution. If torque is not considered to be
accurate enough for these critical joints, an
alternative method of tightening called TORQUE
ANGLE may be used.
Torque Angle Method
4963
4. Thread the thread insert onto the mandrel of

the installer. Engage the tang of the insert onto
the end of the mandrel.
Important: The insert should be flush to one
turn below the surface.
5. Lubricate the insert with light engine oil
(except when installing in aluminum) and
install the insert.
6. If the tang of the insert does not break off

when backing out the installer, break the tang
off with a drift.
Torque Wrenches
Torque Defined 65532
Torque is defined as the measurement of resistance Torque angle is required for critical joints because it
to turning or rotating. Torque, often called torsional or can help eliminate frictional variations in the joint.
twisting movement, tends to twist a body about an The following are the general steps used for the
axis of rotation. A typical application is the tightening torque angle method:
of a screw. 1. Tighten to a predetermined seating torque to
Torque applied in tightening a common bolt, nut, or remove any compliance out of the joint.
screw is expended in three areas:
2. Turn the fastener to a specified angle of

The head rotation. Use the Torque Angle Meter J 36660.
Bearing surface This is the only acceptable general method for

Clamp load measuring this angle of rotation. Follow the specific
procedure where it is provided.
Clamp Load
About 50 percent of applied torque is used in Torque Wrenches and Techniques
overcoming bearing friction. This is the friction The term TORQUE WRENCH is commonly used to
between the bearing surface of the bolt head, screw describe a type of measuring tool. The tool is set or
head or nut face, and the base material or washer calibrated in such a way as to make possible the
(the surface the fastener is rotating on). measurements of the resistance to turning (torque).
Approximately 40 percent of the applied torque is The torque wrench measures this resistance to
used in overcoming thread friction. This leaves only turning and, therefore, is the method used to obtain
about 10 percent of the applied torque to develop objective tightening data used in the assembly of
useful clamp load. Clamp load is the force that holds fasteners. A torque wrench is a gage tool that can
a joint together. Friction can account for as much as be compared with micrometers, dial indicators,
90 percent of the applied torque on a fastener. vernier calipers, levels, and other measuring devices.
1998 -
MD-lsuzu
Tapered Beam Model Torque Wrench Pivoted Handle Torque Wrench
65520 289952
Of the many different types of torque wrenches Some types of torque wrenches are equipped with a
pivoted handle. If used properly, this handle permits
available, the most popular in the service field is the
the accurate and correct use of the torque wrench.
tapered beam model. This model uses a pointer In order to hold a pivoted type handle, it should be
attached to the head that runs the length of the floated on the pivot point. This concentrates your
flexible beam (shaft) to a scale located near the pulling force. If the pivoting handle comes in contact
handle. As the wrench is pulled, the beam bends with the yoke extension during the process of pulling,
and the pointer indicates the torque on the scale. there is a very good chance the torque readings will
be inaccurate because this could alter the wrench
Click-type Torque Wrench loading point. The design of the handle, however,
makes it inconvenient to deliberately use the floating
principle improperly.
Direct Reading Torque Wrench
6484
Another type of torque wrench is the CLICK type

which is adjusted to a predetermined torque. Once
the designated torque has been reached, the wrench 6486
has a reflex signalling feature that causes a Some of the newer model wrenches, such as the
momentary breakaway of the body of the torque Snap-on Direct Reading Torqometer wrench (Model
wrench. This feature has the effect of sending a TES or equivalent) can be held at any position on
strong impulse to the technician's hand. Although the wrench without affecting accuracy. These
once quite popular, these wrenches are not the wrenches are preferred over the flexible beam types
preferred method for torque applications. because of their greater degree of accuracy,
compact design, and scales that are easily readable.
1998 -
MD-lsuzu
Torque Wrench Accuracy Abbreviations Table

Selecting the proper size and range of torque
a
Abbreviation Meaning
wrench is important in obtaining accurate results. A
The best quality torque wrenches (the Snap-on
Direct Reading Torqometer models or equivalent) are A/C Air Conditioning
accurate within 2 percent of the indicated reading AC Alternating Current

from 20 percent of full scale to full scale. For ACL Air Cleaner
example, a 200 N.m (148 Ib ft) full scale torque
ADJ Adjust
wrench is guaranteed to be accurate from 40 N.m to
200 N.m (30-148 Ib ft) (20-100 percent of full scale). A/F Air/Fuel (Ratio)
Using this wrench below 40 N.m (30 Ib ft) (its AIR Secondary Air Injection
guaranteed operating range) could result in
Alt Altitude
inaccurate torque readings and possible joint failure
due to either an overtorque or undertorque condition. AMP Ampere(s)
AM/FM AM/FM Stereo
Torque Wrench Selection
Ant Antenna
Since it is not possible to purchase one wrench to fit
AP Accelerator Pedal
the widest range of torque specifications in the
service environment, the following guidelines should ASM Assembly
be used for torque wrench selection: AT Automatic Transmission

0-20 N.m Full Scale (177 Ib in). Accurate from ATDC After Top Dead Center
4-20 N.m (35-177 Ib in). Auth Authority

0-75 N.m Full Scale (55 Ib ft). Accurate from
Auto Automatic
15-75 N.m (11-55lbft).
B
.
0-250 N.m Full Scale (185 Ib ft). Accurate from
50-250 N.m (37-185 Ib ft). B+ Battery Positive Voltage
BARO Barometric (pressure)

Torque Wrench Calibration
Bat Battery
This is a general guideline and is published to
BP Back Pressure
facilitate the selection of a range or torque wrenches
that would cover most applications and would remain BTDC Before Top Dead Center
in the guaranteed accuracy ranges of the wrenches. C
Once a wrench is put into service, nothing
C Degrees Celsius
guarantees that the wrench will remain calibrated
within its accuracy range. It is recommended, CAC Charge Air Cooler
therefore, that torque wrenches be calibrated a Calif California
minimum of twice annually. Once again, the torque CCOT Cycling Clutch Orifice Tube
wrench is a precision measuring device. The torque
CD Compact Disc
wrench is exposed to rugged working conditions.
Precautions must be taken in order to protect against CFI Continuous Fuel Injection
inaccurate measurements. CFM Cubic Feet Per Minute
CID Cubic Inch Displacement
Continuous Pull Method
CKP Crankshaft Position
Once torque wrench is selected, use a technique
a
called the CONTINUOUS PULL METHOD in order to CL Closed Loop

increase accuracy during torquing. Pull the torque cm Centimeters
wrench in one continuous, smooth action until the
specified torque is reached. There is no jerking or CMP Camshaft Position
ratcheting during this final tightening effort. The CO Carbon Monoxide
continuous pull method is an excellent way to Coax Coaxial
develop consistency.
Conn Connector
Abbreviations and Their Meanings Conv Converter
The following abbreviations may appear in CPP Clutch Pedal Position

this manual. CPS Central Power Supply
Crank Crankshaft
CTP Closed Throttle Position
CV Constant Velocity
1998 -
MD-lsuzu
Abbreviations Table (cont'd) Abbreviations Table (cont'd)

Abbreviation Meaning Abbreviation Meaning
Cyl Cylinder(s) gnd Ground
D GVW Gross Vehicle Weight
DC Direct Current GVWR Gross Vehicle Weight Rating
DFI Direct Fuel Injection H
Diff Differential Ham Harness

Dl Distributor Ignition HC Hydrocarbons
Dist Distributor HD Heavy Duty
DLC Data Link Connector Hg Mercury
DTC Diagnostic Trouble Code Hi Alt High Altitude
DTM Diagnostic Test Mode H02S Heated Oxygen Sensor

DVM Digital Voltmeter hp Horse Power
E 1
EAC Electric Air Control IAC Idle Air Control
EAS Electric Air Switching IAT Intake Air Temperature

ECL Engine Coolant Level 1C Ignition Control
ECM Engine Control Module ICM Ignition Control Module
EOT Engine Coolant Temperature ID Identification or Inside Diameter

ECU Engine Calibration Unit (PROM) IFI Indirect Fuel Injection
Electronically Erasable Programmable ign Ignition
EEPROM
Read Only Memory ILC Idle Load Compensator
EFE Early Fuel Evaporation
INJ Injection
EGR Exhaust Gas Recirculation INT Intake
Exhaust Gas Recirculation Thermal 1/P Instrument Panel
EGRTVV
Vacuum Valve
IPC Instrument Panel Cluster
El Electronic Ignition
ISC Idle Speed Control
EM Engine Modification
K
Erasable Programmable Read Only
EPROM kg Kilogram
Memory
ESC Electronic Spark Control km Kilometer
ESD Electrostatic Discharge km/h Kilometers per hour
ETR Electronically Tuned Receiver kPa Kilopascals
EVAP KS Knock Sensor

Evaporative Emission
kV Kilovolts
Exh Exhaust
F L
Ib Pound(s)
F Degrees Fahrenheit
FC Fan Control Ibft Pound feet (torque)
Ib in Pound inch (torque)
Federal (all the United States except
FED
California) L Liter (engine displacement)
G LF Left Front
gal Gallon LH Left Hand
GAW Gross Axle Weight LR Left Rear
GAWR Gross Axle Weight Rating LS Left Side
GCWR Gross Combination Weight Rating M
Gen Generator MAF Mass Air Flow

Gov Governor Man Manual
g gram MAP Manifold Absolute Pressure
1998 -
MD-lsuzu
Abbreviations Table (cont'd) Abbreviations Table (cont'd)

Abbreviation Meaning Abbreviation Meaning
MAT Manifold Air Temperature R
Max Maximum RAM Random Access Memory

MC Mixture Control Ref Reference
MDP Manifold Differential Pressure RF Right Front
MFI Multi-Port Fuel Injection RFI Radio Frequency Interference
mi Mile(s) RH Right Hand
MIL Malfunction Indicator Lamp ROM Read Only Memory
Min Minimum RPM Engine Speed (Revolutions Per Minute)
ml Milliliter RPO Regular Production Option
mm Millimeter RR Right Rear
mpg Miles per Gallon RS Right Side

mph Miles per Hour RTV Room Temperature Vulcanizing (sealer)
MST Manifold Surface Temperature RVB Rear Vacuum Brake
mV Millivolt RVR Response Vacuum Reducer
N S
NC Normally Closed SAE Society of Automotive Engineers
N.m Newton-meter (torque) Sec Secondary

NO Normally Open Sl System International
NOx Oxides of Nitrogen sol Solenoid
NVRAM Non-Volatile Random Access Memory SPEC Specification
0 Speedo Speedometer
OBD On-Board Diagnostics SPL Smoke Puff Limiter
OC Oxidation Converter (Catalytic) SRI Service Reminder Indicator
OD Outside Diameter SRT Service Readiness Test
OL Open Loop ST Scan Tool
02 Oxygen syn Synchronize
02S Oxygen Sensor T
oz Ounce(s) TAG Throttle Actuator Control

P Tach Tachometer
PAIR Pulsed Secondary Air Injection TCC Torque Converter Clutch
P/B Power Brakes TCM Transmission Control Module
PCM Powertrain Control Module TEMP Temperature
PCV Positive Crankcase Ventilation TDC Top Dead Center
PNP Park/Neutral Position Term Terminal
PRESS Pressure Themno Thermostatic Air Cleaner

PROM Programmable Read Only Memory TP Throttle Position
PS Power Steering TRANS Transmission

psi Pounds per Square Inch TV Throttle Valve
Pt Pint TVRS Television and Radio Suppression
PTO Power Take Off TVV Thermal Vacuum Valve

PWM Pulse Width Modulated TWC Three Way Converter (Catalytic)
Q Three Way + Oxidation Converter
TWC+OC
(Catalytic)
qt Quart(s)
7993 -
MD-lsuzu
Abbreviations Table (cont'd) Identify keys by the five-character key code stamped
onto the key. Use the code numbers and a code list
Abbreviation Meaning in order to determine the lock combination of the
U vehicle. The owners of key cutting equipment receive
the code list from equipment suppliers. If the code
U-Bolt Universal Bolt
number is not available from records or from the
U-Joint Universal Joint five-character key code number, a key code number
V label is on the inside of the bottom glass on the
V6
passenger's side door.
Six Cylinder Engine, V-Type
V8 Eight Cylinder Engine, V-Type Key Code Diagram
V Volt(s)
V-ref ECM Reference Group

Vac Vacuum
VAF Volume Air Flow
VDOT Variable Displacement Orifice Tube
VIN Vehicle Identification Number
^
VR Vacuum Regulator
VRV Vacuum Reducer Valve
VSS Vehicle Speed Sensor
W
12345678 1234
W/ With
W/B Wheel Base

W/0 Without
WOT Wide Open Throttle
Warm Up Oxidation Converter
WU-OC (Catalytic)
205851
Legend
Warm Up Three Way Converter
WU-TWC
(Catalytic)
(1) Position
(2) Level
Key and Lock Cylinder Coding Cutting Keys

Medium Duty Trucks use a one-key locking system. 1. Determine the code from the code list or the
A single, two-sided key operates the ignition and key code diagram.
both doors. The key is reversible, and inserts with 2. Cut a blank key to the proper level for each of
either side facing up. the eight tumbler positions.
3. Ensure that the key locks and unlocks the lock

cylinder.
Replacement Lock Cylinders

The service parts warehouses offer lock cylinders as
a complete assembly, including the key. Do not
service or code the lock cylinders. If a lock cylinder

is faulty, replace the cylinder. Order lock cylinders
^ from the service parts warehouses.
Lifting and Jacking the Vehicle

Caution: To help avoid a personal injury when a
vehicle is on a hoist, provide additional support
for the vehicle at the opposite end from which
components are being removed. This will reduce
the possibility of the vehicle falling off the hoist.
Notice: When jacking or lifting a vehicle at
prescribed lift points, be certain that lift pads do not
contact the exhaust system, brake pipes, cables, fuel
205853 lines or under body. Such contact may result in
damage or unsatisfactory vehicle performance.
1998 -
MD-lsuzu
Any time you lift a vehicle on one end, chock the Tilting the Cab
wheels at the opposite end. Use jack stands in order
to provide support. When supporting the vehicle
using jack stands, place the jack stands under the
side rails or the axle.
Park the vehicle on a clean, hard, level surface
before lifting the vehicle. Ensure that the lifting
equipment meets weight requirements. Ensure that
the lifting equipment is in good working order. Before
lifting the vehicle, ensure that the vehicle loads are
secure and equally distributed. In some cases only
the frame side rails are able to support the vehicle.
Do not put excessive stress on the frame side rails.
You may lift and support the front of the vehicle at
the front axle near the wheel assemblies.
In order to remove the front axle, support the vehicle
near the rear front spring support brackets using
suitable jack stands and/or other lifting equipment.
The lifting points for the front frame are just behind
the rear front spring support brackets.
205878
You may lift and support the rear of the vehicle at
the rear axle near the wheel assemblies. Do not Caution: A tilt cab not properly locked in the
support the vehicle at the differential assembly. tilted position could fall, causing serious injury.
To insure that the cab Is securely locked In
In order to remove the rear axle, support the vehicle
position and won't move, the safety lockpin must
at the frame side rails and the rear crossmember,
always be inserted into the cab support when the
just in front of the rear spring brackets.
cab is in the tilted position.
When you are removing the vehicle's major
Caution: Things that burn can get on hot engine
components while the vehicle is on a hoist, chain the
vehicle frame to the hoist pads nearest the
parts and start a fire. These include liquids like
gasoline or diesel fuel, oil, brake fluid, windshield
component to be removed. Chaining the vehicle to
the hoist pads will prevent tip-off.
washer and other fluids and plastic or rubber. Be
careful not to drop or spill things that will burn
Cab Tilting onto a hot engine.
In order to gain access to the components under the 1. Remove the leverpin. Turn the pin in order to
align the tab with the slot.
cab, complete the following procedure:
Before Tilting the Cab
1. Park the vehicle in a level place.
2. Secure all loose articles in the cab.
3. Close the cab doors.
4. Inspect the area for sufficient clearance in front

of and above the cab.
5. In order to prevent the vehicle from moving,

take the following steps:
Apply the parking brake.

Place an automatic transmission in
PARK (P).
Place a manual transmission in
NEUTRAL (N).

Turn the engine OFF.
Block both the front and the rear wheels.
205879
2. Move the primary tilt lever all the way

downward.
1998 -
MD-lsuzu
205872 205871
3. Pull the secondary latch lever in order to 5. Tilt the cab all the way forward until the cab
release the hook from the catch at the back of support(3) under the cab is fully locked.
the cab. Now the cab is able to tilt.
205876
6. Remove the lockpin(2) from the retainer(4) on

205877
4. Use the handle located at the bottom of the the cab support(3).
cab at the back in order to rotate the cab
7. Insert the lockpin(2) into the hole in the
forward. Torsion bars located under the cab cab support.
assist the tilting.
Caution: A tilt cab not properly locked in the
tilted position could fall, causing serious Injury.
To insure that the cab Is securely locked in
position and won't move, the safety lockpin must
always be inserted into the cab support when the
cab is in the tilted position.
Caution: Things that bum can get on hot engine
parts and start a fire. These include liquids like
gasoline or diesel fuel, oil, brake fluid, windshield
washer and other fluids and plastic or rubber. Be
careful not to drop or spill things that will burn
onto a hot engine.
1998 -
MD-lsuzu
When you are ready to lower the cab, complete the

following procedure:
Lowering the Cab
205869
4. Use the handle located at the bottom of the

cab toward the back in order to lower the cab
until the hook catches and holds the cab down.
205858
1. Rotate and pull on the lockpin(2) in order to

remove the lockpin(2) from the cab support(3).
2. Insert the lockpin(2) into the retainer(4) on the
cab support(3).
205861
5. Push the primary tilt lever upward fully in order

to lock the cab to the chassis.
205859
3. Squeeze the lock lever(1) on the cab support in

order to release the detent.
1998 -
MD-lsuzu
Vehicle Towing with the Front Bumper Removed
1. Remove the front bumper.
205855
6. Replace the lever pin. Insert and turn the pin in

order to align the tab with the slot.
205857
Towing a Disabled Vehicle 2. Connect and lock the lift chains to the front
axle, outside of the spring anchor plates.
When towing a Medium Duty Truck, take the
following precautions in order to prevent damage to 3. Place a hardwood beam underneath and
slightly behind the front spring shackle brackets.
the vehicle:
.
Use an Isuzu dealer or a professional 4. Connect the lift chains to the tow bar.
towing service in order to tow a disabled 5. Raise the tow bar until the lift chain cinches up
Commercial Truck. and the hardwood beam seats fully against the
spring shackle brackets.
Use proper equipment.
6. Raise the vehicle to the required height.

Turn on the hazard warning flashers (if they are
not damaged). To Tow a Vehicle with the Front Bumper Installed
.
Connect the towing components to the main
structural parts of the vehicle.
Do not attach towing components to the
following parts:
-
Bumpers
-
Tow hooks
-
Brackets
. Only use equipment designed for towing.
Follow the instructions given by the tow truck
manufacturer.
.
Use a safety chain system.
Front End Towing (Front Wheels off

the Ground)
Before Towing
Block the rear wheels of the disabled vehicle. On
vehicles with air brakes, release the parking brake
system by compressing the brake chamber springs. 205857
Refer to Air Brakes. Releasing the parking brake 1. Remove the front bumper.
system prevents the parking brake from engaging
2. Connect and lock the lift chains to the front
while the vehicle is in tow.
axle, outside of the spring anchor plates.
On vehicles with hydraulic brakes, release the
3. Place a hardwood beam underneath and
parking brake fully by moving the lever handle to the slightly behind the front spring shackle brackets.
fully released position.
4. Connect the lift chains to the tow bar.
1998 -
MD-lsuzu
5. Take up the slack in the chains until the tow After Towing
bar is within four inches of the front bumper . Block the rear wheels and install the axle
facing.
shafts. Refer to Axle Shaft Replacement in
6. Remove the remaining slack in the lift chains. Driveline/Axle.
7. Raise the vehicle to the required height. Install the propeller shafts and inspect for
8. Prepare the axles. Refer to Preparing the Axles proper phasing of the universal joints. Refer to
Before Towing the Vehicle in this section. one of the following procedures in
Driveline/Axle:
Preparing the Axles Before Towing
the Vehicle

One-Piece Propeller Shaft Replacement
Single Drive Rear Axle

Two or Three Piece Propeller Shaft
Replacement
1. Remove the rear axle shafts. Refer to Axle
Shaft Replacement in Driveline/Axle. Apply the parking brake before disconnecting
the Truck from the towing vehicle.
2. Cover the hub openings in order to prevent loss
of the lubricant or lubricant contamination.
Rear End Towing (Rear Wheels Off
After Towing the Ground)
1. Block the rear wheels and install the axle
Before Towing
shafts. Refer to Axle Shaft Replacement in
Driveline/Axle. Secure the steering wheel
in order to maintain
a straight-ahead position.
2. Install the propeller shafts, and inspect the
universal joints for proper phasing. Refer to one
Ensure that the front axle is not loaded above
of the following procedures in Driveline/Axle: the front axle Gross Axle Weight Rating (GAWR).

One-Piece Propeller Shaft Replacement The GAWR is located on the Vehicle

Two- Piece Propeller Shaft Replacement Certification Label.
Three- Piece Propeller Shaft Replacement

After Towing
Apply the parking brake before disconnecting Block the rear wheels.
3.
theTruck from the towing vehicle.
Release the steering.
4. Inspect the fluid level in the rear axle. Fill the Apply the parking brake before disconnecting
rear axles with oil as required. from the towing vehicle.
Front End Towing (All Wheels on the Ground) .

Inspect the fluid level in the rear axle.
Fill the rear axle with oil as necessary.
You may tow the vehicle on all wheels, provided that
the steering is operable. The power brakes and

power steering will not have power assist. Vehicles Special Towing Instructions
with air brakes will not have braking capability. Call a local Isuzu dealer or a professional
Ensure that there is a tow bar between the towing towing service.
vehicle and the disabled vehicle. Follow all the state and local laws regarding
Before Towing towing:
Block the wheels of the disabled vehicle.
Warning signals

On vehicles with air brakes, release the parking Night illumination
brake system by compressing the brake

Speed
chamber springs. Refer to Air Brakes.
Releasing the parking brake will prevent the
Do not tow any vehicle over 90 km/h (55 mph).
parking brake from engaging while the vehicle If a vehicle is damaged, secure any loose or
is in tow.
protruding parts prior to towing.

Disconnect the propeller shaft at the rear axle
Use a safety chain system that is completely
(forward unit on tandem axles). Refer to one of
independent of the primary lifting and towing
the following procedures in Driveline/Axle:
attachment.

One-Piece Propeller Shaft Replacement Do not go underneath a raised vehicle unless

Two-Piece Propeller Shaft Replacement the vehicle is supported by safety stands.

Three-Piece Propeller Shaft Replacement Do not perform any towing operation that may

Secure the propeller shaft to the frame or the risk the safety of the tow truck operator,
crossmember. bystanders or other motorists.
If there is damage or suspected damage to the
rear axle, remove the axle shafts. Refer to Axle
Shaft Replacement in Driveline/Axle.

Cover the hub openings in order to prevent loss
of lubricant or lubricant contamination.
1998 -
MD-lsuzu
Strategy Based Diagnosis 5.3. Intermittents: Conditions that are not

Strategy based diagnostics is a uniform approach to always present are intermittent. In order
to resolve intermittents, perform the
repair all electrical/electronics systems. The following. Observe the history for similar
diagnostic flow can always be used to resolve an
cases where repair history may be
E/E system problem and is the place to start when
available. Combine the technician
repairs are necessary. Refer to the following chart for knowledge with efficient use of the
proper strategy based diagnostics. available service information. Evaluate
1. Verify the complaint: In order to verify the the symptoms and conditions described
complaint the technician should know the by the customer. Use a check sheet or
normal operation of the system. other method in order to identify the
circuit or electrical system component.
2. Preliminary Checks: Conduct a thorough visual Follow the suggestions for intermittent
inspection. Review the service history. Detect diagnosis found in the service
unusual sounds or odors. Gather diagnostic documentation. The Tech 1, Tech 2 and
trouble code information in order to achieve an Fluke 87 scan tools have data capturing
effective repair. capabilities that can assist in detection of
intermittents.
3. Perform Published Diagnostic System Checks:
One or more DTCs may not support a system. 5.4. Vehicle Operates as Designed: This
System checks verify the proper operation of condition exists when the vehicle is found
the system. This will lead the technician in an to operate normally. The condition
organized approach to diagnostics. described by the customer may be
normal. Verify against another vehicle
4. Check Bulletins and Other Service Information: that is operating normally. The condition
Also checks the videos, the newsletters, etc.
may be intermittent. Verify the complaint
5. Check for any stored DTCs: Follow the under the conditions described by the
designated DTC steps exactly in order to make customer before releasing the vehicle.
an effective repair. 6. Re-examine the Concern: If a technician cannot
successfully find or isolate the complaint, a
5.1. Symptom No DTC: Select the symptom.
Follow the diagnostic steps or reevaluation is necessary. Re-verify the
suggestions in order to complete the complaint. The complaint could be an
intermittent or normal.
repair, or refer to the applicable
component/system check. 7. Repair and Verify Fix: After isolating the cause,
make the repairs. Then validate for proper
5.2. No Published Diagnostics: Analyze the operation. Verify that the symptom has been
complaint. Develop a plan for the
corrected. Verification may involve road testing
diagnostics. Utilize the wiring diagrams
the vehicle.
and theory of operation.
1998 -
MD-lsuzu
General Information Maintenance and Lubrication 0-33
Maintenance and Lubrication

Specifications
Approximate Fluid Capacities

Specification
Application Metric English
Automatic Transmission AT545
Shallow Pan 8.5 liters 18.0 pints
Deep Pan 15.0 liters 32.0 pints
Shallow Pan (Overhaul only) 14.0 liters 30.0 pints
Deep Pan (Overhaul only) 21.0 liters 44.0 pints
Cooling System
7.8L (W/Automatic Transmission) 30.3 liters 32.0 quarts

Dana Rear Axle Single-Speed Model (See Note A)
S150S (RPO-H08) 13.0 liters 13.8 quarts
Eaton Rear Axle Single-Speed Models (See Note A)
15040S (RPO-H10) 10.1 liters 10.7 quarts
15050S (RPO-HWY) 12.8 liters 13.5 quarts
15050S (RPO-HZW) 12.8 liters 13.5 quarts
15050S (RPO-H11) 12.8 liters 13.5 quarts
15060S (RPO-HPK) 14.6 liters 15.5 quarts
21060S (RPO-HPP) 14.6 liters 15.5 quarts
22060S (RPO-HPG) 14.6 liters 15.5 quarts
23080S (RPO-HPQ) 20.3 liters 21.5 quarts
23105S (RPO-HNA) 24.1 liters 25.5 quarts
Eaton Rear Axle Two Speed Models (See Note A)
19050T (RPO-HZT) 16.8 liters 17.8 quarts
19060T (RPO-HPM) 18.0 liters 19.0 quarts
21060T (RPO-H15) 17.5 liters 18.5 quarts
22060T (RPO-HPH) 17.5 liters 18.5 quarts
23080T (RPO-H20) 21.0 liters 22.0 quarts
Engine Crankcase
7.8L Engine 14.0 liters 14.79 quarts

Fuel Tanks
Standard Fuel Tanks (RPO NLO) 189.0 liters 50.0 gallons

Optional Fuel Tanks (RPO NL5) 378.0 liters 100.0 gallons
Manual Transmission
5-Speed Fuller FS5005A 5.0 liters 10.5 pints
6-Speed with PTO 7.2 liters 15.22 pints
6-Speed without PTO 6.5 liters 13.74 pints
These quantities include 1.5 liters (3.2 pints) in order to fill the hub cavities.
1998 -
MD-lsuzu
0-34 Maintenance and Lubrication General Information
Fluid and Lubricant Recommendations Fluid and Lubricant Recommendations

(cont'd)
Air Brake System Alcohol Commercial grade of
Evaporator methyl alcohol Front Wheel Bearings with SAE 75W-90 synthetic axle
Oil Filled Hubs lubricant.
Brake Caliper Housing, the
Caliper Support Spring, and Aeroshell #5 grease DOT-3 brake fluid. Hydraulic
Hydraulic Brake System
the Caliper Support Key Brake System
Cab-Door Hinges Power Steering System Power steering fluid.
Engine oil
and Latches
Wheel bearing lubricant that
Chassis lubricant that meets meets the requirements of
Propshafts and Splines
the requirements of NLGI NLGI Grade 2, Category GC
Chassis Lubricant
Brake 2, Category LB or GC-LB.
or GC-LB SAE 75W-90 synthetic gear
Rear Axle
High-temperature grease of lubricant.
Clutch Bearing Lubricant
NLGI #3 consistency
Rear Axle Shift Motor Refrigerant Oil
50/50 mixture of clean
Spring Parking Brake DEXRON-111 automatic
drinkable water and
Hydraulic Pump transmission fluid.
DEX-COOL or Havoline
Engine Coolant NLGI Category GC-LB
DEX-COOL antifreeze Steering Shaft and Clutch
(orange-colored, #2 multi-purpose type
Shift Block
silicate-free). grease.
Engine oil with the Multi-purpose gear oil
letters CG-4 is best for your Manual Transmission Fluid SAE 90 GL5 (SAE 80 W
vehicle. If CG-4 is not -90 GL5 in Canada).
available, you may use DEXRON-111 automatic
CF-4/SH oil (see Note A). Automatic
Engine Oil transmission fluid or
In order to determine the Transmission Fluid
Type C-4.
preferred viscosity for your
NLGI Category GC-LB #2 or
vehicle's diesel engine, refer
Water Pump #3 multi-purpose type
to Engine Oil in the ISUZU
grease.
Owner's Manual.
Weatherstrip Conditioning Dielectric silicone grease
Exhaust Brake Ball Joint High-temperature grease of
Cap Lubricant NLGI #3 consistency Wheel bearing lubricant that
meets the requirements of
Wheel Bearing Grease
NGLI Grade 2, Category GC
or GC-LB
Maintenance Items
Item Part Identification
Fuel Filter (Primary) Raycor (NWB) B32002
Fuel Filter (Secondary Engine Mounted) 1-13240-074-0
Oil Filter 1-13200-487-2
1998 -
MD-lsuzu
Maintenance
Inspect the clutch pedal for free travel. (10)

Lubricate the clutch shift block (or every month,
Maintenance Schedule whichever occurs first).
Perform the services in this schedule up
Perform the shields and the underhood
to 161 000 km (100 000 mi) and after insulation service (or every month, whichever
161 000 km (100 000 mi) at the same intervals. occurs first). (4, 5, 21)
Refer to Explanation of Scheduled Services for 15 700 km (9,750 mi)
further explanations of maintenance services
Inspect the fluid levels (or every 3 months,
and footnotes. whichever occurs first). (3, 6)
160 km (100 mi) Lubricate the clutch shift block (or every month,
Perform the wheel stud nut service. (45) whichever occurs first).
800 km (500 mi) Clean the air conditioner filter (or every month,

Perform the wheel stud nut service. (45) whichever occurs first). Refer to Passenger
1 600km (1,000 mi) Compartment Air Filter Replacement in HVAC.
Perform the wheel stud nut service. (45,46) 20800km (13,000 mi)
5 200 km (3,250 mi)
Change the engine oil and the filter (or every
3 months, whichever occurs first). (3, 9)

whichever occurs first). (3, 6)


Perform the chassis lubrication service (or every
Inspect and clean the air conditioner filter (or

6 months, whichever occurs first). (12)
every month, whichever occurs first).
Clean the air conditioner filter (or every month,

whichever occurs first). Refer to Passenger

whichever occurs first). Compartment Air Filter Replacement in HVAC.
Service the rear axle air shift motor. (11)

Lubricate the water pump (or every 3 months,
10400km (6,500 mi) whichever occurs first).

Lubricate the steering column shaft (or every
3 months, whichever occurs first). (3, 9) 3 months, whichever occurs first).

Lubricate the door hinge pins and the rollers
whichever occurs first). (3, 6) using engine oil.

Perform the steering system inspection. (13)
Inspect the automatic transmission fluid level
(or every month, whichever occurs first). (1)

Inspect the manual transmission fluid level (or
Compartment Air Filter Replacement in HVAC. every 3 months, whichever occurs first). (2)
Perform the front and rear suspension
whichever occurs first). service. (14)

Perform the spring-to-axle U-bolts and the
. Lubricate the steering column shaft (or every
3 months, whichever occurs first). shackle bolts service. (16)
Perform the wheels and tires service. (15)

using engine oil.
Perform the brake service (or every 6 months,
whichever occurs first). (7)

Replace the automatic transmission fluid and
Perform the hydraulic parking brake service
the filter (or every 12 months, whichever occurs
(or every 6 months, whichever occurs first). (8)
first). (1)

every 3 months, whichever occurs first). (2)

whichever occurs first).
Verify the curb idle speed (or every 12 months,
Perform the throttle linkage service. (19)

Inspect the exhaust system (or every month,
whichever occurs first). (3, 4, 17)
service. (14)

Perform the thermostatically controlled engine
Perform the spring-to-axle U-bolts and the cooling fan service. (4, 20)
shackle bolts service. (16)
.
Perform the wheels and tires service. (15) insulation service(or every month, whichever
Perform the brake service (or every 6 months, occurs first). (4, 5, 21)
whichever occurs first). (7) Verify the operation of the air brake relay valve
.
Perform the hydraulic parking brake service (or and inspect for leaks (or every month or every
every 6 months, whichever occurs first). 300 hours, whichever occurs first).
1998 -
MD-ISUZU
26 000 km (16,250 mi) 36 400 km (22,750 mi)

whichever occurs first). (3, 6) whichever occurs first). (3, 6)

Clean air conditioner filter (or every month,
Clean air conditioner filter (or every month,
whichever occurs first). whichever occurs first).

31 400 km (19,500 mi) 41 600 km (26,000 mi)

3 months, whichever occurs first). (3, 9) 3 months, whichever occurs first). (3, 9)
whichever occurs first). (3, 6) whichever occurs first). (3, 6)
Perform the chassis lubrication service (or every Perform the chassis lubrication service (or every
6 months, whichever occurs first). (12) 6 months, whichever occurs first). (12)
Clean the air conditioner filter (or every month, Clean the air conditioner filter (or every month,
whichever occurs first). Refer to Passenger whichever occurs first). Refer to Passenger
Compartment Air Filter Replacement in HVAC. Compartment Air Filter Replacement in HVAC.
.
Lubricate the water pump (or every 3 months, Lubricate the water pump (or every 3 months,

3 months, whichever occurs first). 3 months, whichever occurs first).
Inspect door hinge pins and bushings and

replace as necessary. replace as necessary.

. Lubricate the door hinge pins and the rollers
using engine oil.
using engine oil.
Perform the steering system inspection. (13) Perform the steering system inspection. (13)

Inspect the automatic transmission fluid level (or
every month, whichever occurs first). (1) the filter (or every 12 months, whichever occurs

Inspect the manual transmission fluid level (or first). (1)

Perform the front and rear suspension every 3 months, whichever occurs first). (2)
service. (14)
Inspect the fuel injection fuel lines (or every
Perform the spring-to-axle U-bolts and the 12 months, whichever occurs first). (26)
shackle bolts service. (16) Perform the front and rear suspension
Perform the wheels and tires service. (15) service. (14)
Perform the brake service (or every 6 months, Perform the spring-to-axle U-bolts and the
whichever occurs first). (7) shackle bolts service. (16)
Perform the hydraulic parking brake service (or Perform the wheel bearing service (or every
every 6 months, whichever occurs first). (8) 24 months, whichever occurs first and whenever
Inspect the clutch pedal for free travel. (10) the hubs are removed). (23)
Lubricate the clutch shift block (or every month, Perform the wheels and tires service. (15)

Inspect the exhaust system (or every month, whichever occurs first). (7)
whichever occurs first). (3, 4, 17) Perform the hydraulic parking brake service (or
Perform the shields and the underhood every 6 months, whichever occurs first). (8)
insulation service (or every month, whichever Perform the engine drive belts service (or every
occurs first). (4, 5, 21) 12 months, whichever occurs first). (18)
Perform the hydraulic brake caliper system Inspect the clutch pedal for free travel. (10)
service (or every 6 months, whichever occurs
first). (22)

Perform the air brake service (or every
Perform the throttle linkage service. (19)

Clean the air brake application valve (or every
3 months, or every 300 hours, whichever occurs whichever occurs first). (3, 4, 17)
first). Lubricate the linkage.
1998 -
MD-lsuzu

cooling fan service. (4, 20) every month, whichever occurs first). (1)

insulation service (or every month, whichever every 3 months, whichever occurs first). (2)
occurs first). (4, 5, 21)
Inspect the air intake system (or every
24 months, whichever occurs first). (4, 5, 24) whichever occurs first). (7)
Air brake automatic slack adjuster service (or
Perform the hydraulic parking brake service (or
every 500 hours, whichever occurs first). (40) every 6 months, whichever occurs first). (8)

Replace the fuel filter (or every 24 months,
whichever occurs first. (3)


Replace the air cleaner filter (or every whichever occurs first).
24 months, whichever occurs first. (3, 4, 27)


Pereform the rear axle air shift motor insulation service (or every month, whichever
service. (11) occurs first). (4, 5, 21)

Perform the air brake service (or every 57 200 km (35,750 mi)
6 months, whichever comes first). (39)
Verify the operation of the air brake relay valve whichever occurs first). (3, 6)
and inspect for leaks (or every month or every
300 hours, whichever occurs first).

Inspect the operation of the air brake chamber Compartment Air Filter Replacement in HVAC.
(or every 2 months, whichever occurs first). (41)
.

Perform the trailer brake hand control valve whichever occurs first).
service (or every 3 months, or 900 hours, 62 400 km (39,000 mi)
Inspect the starter brushes for wear (or every

12 months, whichever occurs first). Replace the

brushes as necessary.
Inspect the generator brushes for wear (or

every 12 months, whichever occurs first). 6 months, whichever occurs first). (12)
Replace the brushes as necessary.
46 800 km (29,250 mi)

Compartment Air Filter Replacement in HVAC.

Clean air conditioner filter (or every month, whichever occurs first).
whichever occurs first). Refer to HVAC Air Filter

Replacement in HVAC.
3 months, whichever occurs first).
replace as necessary.
52 000 km (32,500 mi)

Lubricate the door hinge pins and rollers using

Change the engine oil and the filter (or every engine oil.


every month, whichever occurs first). (1)

Replace the manual transmission fluid (or every

Perform the spring-to-axle U-bolts and the
Compartment Air Filter Replacement in HVAC. shackle bolts service. (16)
whichever occurs first). whichever occurs first). (7)
3 months, whichever occurs first). every 6 months, whichever occurs first). (8)
.

engine oil.

Perform the cooling system service (or every whichever occurs first).
12 months, whichever occurs first). (3, 35) Perform the throttle linkage service. (19)
1998 -
MD-lsuzu
whichever occurs first). (3, 4, 17) insulation service (or every month, whichever

Perform the thermostatically controlled engine occurs first). (4, 5, 21)
cooling fan service. (4, 20) 78 000 km (48,750 mi)

Perform the shields and the underhood Inspect the fluid levels (or every 3 months,
insulation service (or every month, whichever whichever occurs first). (3, 6)
Perform the hydraulic brake capliper system whichever occurs first). Refer to Passenger
service (or every 6 months, whichever occurs Compartment Air Filter Replacement in HVAC.
first). (22) Lubricate the clutch shift block (or every month,
Perform the air brake service(or every whichever occurs first).
6 months, whichever occurs first). (39) 83 200 km (52,000 mi)
Verify the operation of the air brake relay valve
and inspect for leaks (or every month or every
300 hours, whichever occurs first). Inspect the fluid levels (or every 3 months,

Clean the air brake application valve (or every whichever occurs first). (3, 6)
3 months, or every 300 hours, whichever occurs
first). Lubricate the linkage. 6 months, whichever occurs first). (12)
67 600 km (42,250 mi)
Clean the air conditioner filter. Refer to

Inspect the fluid levels (or every 3 months, Passenger Compartment Air Filter Replacement
in HVAC.
Compartment Air Filter Replacement in HVAC. Lubricate the steering column shaft (or every


using engine oil.
72 800 km (45,500 mi)

the filter (or every 12 months, whichever occurs
first). (1)

Verify the curb idle speed (or every 12 months,

Clean the air conditioner filter (or every month, whichever occurs first). (20)

Perform the injector service (or every

Inspect fuel injection fuel lines (or every

service. (14)
Lubricate the door hinge pins and rollers using Perform the spring-to-axle U-bolts and the
engine oil. bolts service. (16)
shackle

Perform the wheel bearing service (or every
every month, whichever occurs first). (1) 24 months, whichever occurs first and whenever
Inspect the manual transmission fluid level (or the hubs are removed). (23)
every 3 months, whichever occurs first). (2) Perform the wheels and tires service. (15)
Perform the spring-to-axle U-bolts and the Perform the brake service (or every 6 months,
shackle bolts service. (16) whichever occurs first). (7)


Perform the brake service (or every 6 months, every 6 months, whichever occurs first). (8)
whichever occurs first). (7) Perform the engine drive belts service (or every

Perform the hydraulic parking brake service (or 6 months, whichever occurs first). (18)


Inspect the clutch pedal for free travel. (10) Lubricate the clutch shift block (or every month,
Lubricate the clutch shift block (or every month, whichever occurs first).
Perform throttle linkage service. (19)
1998 -
MD-lsuzu

Inspect the exhaust system (or every month, Lubricate the water pump (or every 3 months,
whichever occurs first). (3, 4, 17) whichever occurs first).

cooling fan service. (4, 20) 3 months, whichever occurs first).

Inspect the door hinge pins and rollers.
insulation service (or every month, whichever Lubricate the door hinge pins and the rollers
occurs first). (4, 5, 21) using engine oil.
Replace the air conditioning filter dryer (or

24 months, whichever occurs first). (4, 5, 24) every 18 months, whichever occurs first, and

Replace the fuel filter (or every 6 months, whenever the refrigerant charge is lost for any
whichever occurs first. (3, 4, 27) reason).

Replace the air cleaner filter (or every
24 months, whichever occurs first). (3) the filter (or every 12 months, whichever occurs
Adjust the valve lash (or every 12 months, first). (1)

Retighten the manifold mounting and the every 3 months, whichever occurs first). (2)
injector bracket nuts to specifications (or every Perform the wheels and tires service. (15)
6 months, whichever occurs first). Perform the brake service (or every 6 months,

Perform the rear axle air shift motor whichever occurs first). (7)
service. (11) Perform the hydraulic parking brake service (or

Perform the air brake service (or every every 6 months, whichever occurs first). (8)
Verify the operation of the air brake relay valve Lubricate the clutch shift block (or every month,
operation and inspect for leaks (or every month whichever occurs first).
or every 300 hours, whichever occurs first).

Inspect the operation of the air brake chamber insulation service (or every month, whichever
(or every 2 months, whichever occurs first). (41) occurs first). (4, 5, 21)

Perform the trailer brake hand control valve
Perform the hydraulic brake caliper service (or
service (or every 3 months, or 900 hours, every 6 months, whichever occurs first). (22)
Air brake automatic slack adjuster service (or 3 months, or every 300 hours, whichever occurs
every 500 hours, whichever occurs first). (40) first). Lubricate the linkage.

Inspect the starter brushes for wear (or every 98 800 km (61,750 mi)
12 months, whichever occurs first). Replace the Inspect the fluid levels (or every 3 months,
brushes as necessary. whichever occurs first). (3, 6)
Inspect the generator brushes for wear (or
every 12 months, whichever occurs first). whichever occurs first). Refer to Passenger
Replace the brushes as necessary. Compartment Air Filter Replacement in HVAC.
88 400 km (55,250 mi)
Inspect the fluid levels (or every 3 months, whichever occurs first).
whichever occurs first). (3, 6) 104000km (65,000m!)
whichever occurs first). Refer to Passenger 3 months, whichever occurs first). (3, 9)
Compartment Air Filter Replacement in HVAC. Inspect the fluid levels (or every 3 months,
. Lubricate the clutch shift block (or every month, whichever occurs first). (3, 6)
93 600 km (58,500 mi) 6 months, whichever occurs first). (12)
.
Change the engine oil and the filter (or every Clean the air conditioner filter (or every month,
3 months, whichever occurs first). (3, 9) whichever occurs first). Refer to Passenger
Inspect the fluid levels (or every 3 months, Compartment Air Filter Replacement in HVAC.
whichever occurs first). (3, 6) Lubricate the water pump (or every 3 months,

Perform the chassis lubrication service (or every whichever occurs first).

Clean the air conditioner filter. Refer to
Passenger Compartment Air Filter Replacement Lubricate the door hinge pins and the rollers
in HVAC. using engine oil.
1998 -
MD-lsuzu

Service the cooling system (or every 12 months Perform the steering system inspection. (13)
since the last service, whichever occurs Inspect the automatic transmission fluid level (or
first). (3, 35)


Inspect the automatic transmission fluid level (or every 3 months, whichever occurs first). (2)

Inspect the manual transmission fluid level (or service. (14)
every 3 months, whichever occurs first). (2) Perform the spring-to-axle U-bolts and the

Perform the front and rear suspension shackle bolts service. (16)
service. (14) Perform the wheels and tires service. (15)


whichever occurs first). (7) Inspect the clutch pedal for free travel. (10)


Lubricate the clutch shift block (or every month, whichever occurs first). (3, 4, 17)
. Perform the shields and the underhood

Perform the throttle linkage service. (19) insulation service (or every month, whichever

Inspect the exhaust system (or every month, occurs first). (4, 5, 21)
whichever occurs first). (3, 4, 17) 119 600 km (74,750 mi)

Perform the thermostatically controlled engine Inspect the fluid levels (or every 3 months,
cooling fan service. (4, 20)
insulation service (or every month, whichever

Perform the air brake service (or every Lubricate the clutch shift block (or every month,
Verify the operation of the air brake relay valve
124 800 km (78,000 mi)
operation and inspect for leaks (or every month
or every 300 hours, whichever occurs first).

109 200 km (68,250 mi)




Lubricate the clutch shift block (or every month, whichever occurs first). Refer to Passenger
whichever occurs first). Compartment Air Filter Replacement in HVAC.
114400km (71,500 mi) Lubricate the water pump (or every 3 months,

3 months, whichever occurs first). (3, 9) Lubricate the steering column shaft (or every
whichever occurs first). (3, 6) Inspect door hinge pins and bushings and
replace as necessary.

6 months, whichever occurs first). (12) Lubricate the door hinge pins and the rollers
using engine oil.
whichever occurs first). Refer to Passenger Perform the steering system inspection. (13)

Lubricate the water pump (or every 3 months, the filter (or every 12 months, whichever occurs
whichever occurs first). first). (1)

Replace the manual transmission fluid (or every
3 months, whichever occurs first). 12 months, whichever occurs first). (2)

Perform the injector service (or every
engine oil. 12 months, whichever occurs first). (25)
1998 -
MD-lsuzu

Perform the front and rear suspension Inspect the starter brushes for wear (or every

service. (14) 12 months, whichever occurs first). Replace the

.
Perform the spring-to-axle U-bolts and the brushes as necessary.
shackle bolts service. (16) Inspect the generator brushes for wear (or

Perform the wheel bearing service (or every every 12 months, whichever occurs first).
24 months, whichever occurs first and whenever Replace the brushes as necessary.
the hubs are removed). (23) 130000km (81,250 mi)


Perform the air brake automatic slack adjuster

service (or every 500 hours, whichever occurs

Perform the engine drive belts service(or every first). (40)
135 200 km (84,500 mi)

Lubricate the clutch shift block (or every month, 3 months, whichever occurs first). (3, 9)
Perform the throttle linkage service. (19) whichever occurs first). (3, 6)
whichever occurs first). (3, 4, 17) 6 months, whichever occurs first). (12)

cooling fan service. (4, 20) whichever occurs first). Refer to Passenger
Perform the shields and the underhood Compartment Air Filter Replacement in HVAC.
occurs first). (4, 5, 21) whichever occurs first).
24 months, whichever occurs first). (4, 5, 24) 3 months, whichever occurs first).

Replace the fuel filter (or every 6 months,
whichever occurs first. (3) engine oil.
Perform the fuel tank, the fuel cap, and the fuel .
lines service(or every 72 months, whichever every 12 months, whichever occurs first). (1)
occurs first). (3, 30)

Replace the air cleaner filter (or every every 3 months, whichever occurs first). (2)
24 months, whichever occurs first). (3, 4, 27) Perform the wheels and tires service. (15)
Perform the rear axle air shift motor
service. (11) whichever occurs first). (7)
Perform the hydraulic brake service (or every Perform the hydraulic parking brake service (or
6 months, whichever occurs first). (22) every 6 months, whichever occurs first). (8)
Perform the air brake service (or every
Verify the operation of the air brake relay valve whichever occurs first).
operation and inspect for leaks (or every month Perform the shields and underhood insulation
or every 300 hours, whichever occurs first). service (or every month, whichever occurs first).

Clean the air brake application valve (or every (4, 5, 21)
3 months, or every 300 hours, whichever occurs 140 400 km (87,750 mi)
first). Lubricate the linkage. Perform the wheel bearing service -
Eaton
Inspect the operation of the air brake chamber Axle (oil filled) (or every 36 months, whichever
(or every 2 months, whichever occurs first). (41) occurs first). (23)
Perform the trailer brake hand control valve
service (or every 3 months, or 900 hours, whichever occurs first). (3, 6)
Air brake automatic slack adjuster service (or whichever occurs first). Refer to Passenger
every 500 hours, whichever occurs first). (40) Compartment Air Filter Replacement in HVAC.

1998 -
MD-lsuzu
145600km (91,000 mi)


Change the engine oil and the filter (or every whichever occurs first). Refer to Passenger
3 months, whichever occurs first). (3, 9) Compartment Air Filter Replacement in HVAC.

Inspect the fluid levels (or every 3 months, .
whichever occurs first). (3, 6) whichever occurs first).

6 months, whichever occurs first). (12) 3 months, whichever occurs first).

Clean the air conditioner filter (or every month, Inspect the door hinge pins and bushings and
whichever occurs first). Refer to Passenger replace as necessary.

Lubricate the water pump (or every 3 months, using engine oil.
whichever occurs first). Perform the cooling system service (or every

Lubricate the steering column shaft (or every 12 months since the last service, whichever
occurs first). (3, 35)
.
Replace the air conditioning filter dryer (or
using engine oil.
every 18 months, whichever occurs first, and
Perform the steering system inspection. (13) whenever the refrigerant charge is lost for any

Inspect the automatic transmission fluid level (or reason).
every month, whichever occurs first). (1) Inspect the automatic transmission fluid level (or
Inspect the manual transmission fluid level (or every month, whichever occurs first). (1)

Perform the front andthe rear suspension every 3 months, whichever occurs first). (2)
service. (14) Perform the wheels and tires service. (15)

Perform the wheels and tires service. (15) Perform the hydraulic parking brake service (or


Perform the hydraulic parking brake service (or Lubricate the clutch shift block (or every month,



Lubricate the clutch shift block (or every month, insulation service (or every month, whichever

Perform the throttle linkage service. (19) Inspect the oil level gauge rubber hose for
Perform the thermostatically controlled engine cracks, damage, or other abnormal conditions
cooling fan service. (4, 20) (or every 12 months, whichever occurs first).

Perform the shields and the underhood Perform the hydraulic brake system service (or
Verify the operation of the air brake relay valve 3 months, or every 300 hours, whichever occurs
and inspect for leaks (or every month or every first). Lubricate the linkage.
300 hours, whichever occurs first).
166 000 km (100,000 mi)
150 800 km (94,250 mi)

Change the power steering fluid (or every


Perform the front axle service (or every
whichever occurs first). Refer to Passenger 36 months, whichever occurs first). (38)
Compartment Air Filter Replacement in HVAC. Perform the exhaust brake service (if equipped).
Lubricate the clutch shift block (or every month, Inspect for excessive spindle free play and
whichever occurs first). smooth operation. Lubricate the ball joint cap.
156 000 km (97,500 mi)
Replace the accelerator control cable (or every

Change the engine oil and the filter (or every 36 months, whichever occurs first). (19)
3 months, whichever occurs first). (3, 9) Perform the air brake valves service (or every

Inspect the fluid levels (or every 3 months, 6 months, or 1800 hours, whichever occurs
whichever occurs first). (3, 6) first). (44)

Perform rear axle service Eaton Axle (or
6 months, whichever occurs first). (12) every 12 months, whichever occurs first). (37)
1998 -
MD-lsuzu
240300km (150,000 mi) At the minimum, perform these routine inspections
Perform the cooling system service (or every every 6 months or 10 000 km (6,000 mi), whichever
60 months since the last service, whichever occurs occurs first. Complete any necessary repairs before
first). (3, 35) operating the vehicle.
320 000 km (200,000 mi) At Each Fuel Fill
Remove, disassemble, clean, and inspect the air
brake trailer supply valve (or every 2 years or Important: Perform these underhood inspections at
each fuel fill.
7,200 hours, whichever occurs first).
400 000 km (250,000 mi) Engine Oil Level Inspection
Inspect the engine oil level. Add the proper oil if

Perform the wheel bearing service Eaton
-
necessary. Refer to Fluid and Lubricant

Axle (oil filled) (or every 36 months, whichever
Recommendations.
occurs first). (23)
Engine Coolant Level Inspection

Service the rear axle Eaton Axles service
-
Inspect the engine coolant level. Add the proper

(or every 36 months, whichever occurs
coolant mix if necessary. Refer to Fluid and
first). (37)
Lubricant Recommendations.
480 000 km (300,000 mi) Windshield Washer Fluid Level Inspection
Remove, disassemble, clean, and inspect the air Inspect the windshield washer fluid level in the
brake dryer (or every 3 years or 10,800 hours, windshield washer tank. Add the proper fluid if
whichever occurs first). Replace the desiccant on
necessary. Refer to Fluid and Lubricant
Bendix Westing House.
Recommendations.
Short Trip/City Tire Inflation Inspection
Inspect the tire inflation. Ensure that the tires are
Notice: One of the reasons you should follow the inflated to the pressures specified on the
Short Trip/City schedule, if you operate your vehicle Certification/Tire label.
under any of these conditions, is that these
conditions cause engine oil to break down sooner. At Least Twice a Year
Restraint System Inspection
Follow this schedule if any one of the following
Ensure that the following components are functioning
conditions is true for your vehicle:
properly:

Most trips are less than 8-16 km (5-10 mi). The belts
This is particularly important when outside
temperatures are below freezing.
The buckles

Most trips include extensive idling and/or low

The latch plates
speed operation (such as door-to-door delivery
The retractors
and frequent driving in stop-and-go traffic).
The anchorages

Most trips are through dusty areas. The reminder systems

The vehicle frequently tows a trailer. Inspect for any other loose or damaged safety belt

The vehicle operates at or near the maximum system parts.
Gross Vehicle Weight (GVW) ratings. Repair any components in a condition that might

The vehicle operates in hilly or mountainous prevent a safety belt system from functioning
properly.
terrain.
Replace any torn or frayed safety belts.
Body Lubrication Service

Long Trip/Highway
Notice: Recommended Fluids and Lubricants tells
Notice: Driving a vehicle with a fully warmed engine you what to use. More frequent lubrication may be
under highway conditions causes engine oil to break required when exposed to a corrosive environment.
down slower. Lubricate all of the following exposed surfaces:
Follow this schedule only if none of the conditions
The door checks
from the Short Trip/City Maintenance Schedule
The door lock bolts
is true.

The lock strike Plates
Owner Checks and Services (General)
The door hinge bushings
Perform the owner checks and services that are The dovetail bumper wedges
listed below at the intervals specified in order to Use a dripless oil where oil holes are provided.
ensure the safety, dependability and emission control Also lubricate the following components:
performance of your vehicle. The seat adjusters
For your safety and the safety of others, inspect any The seat track
of the safety related components that may have
been damaged in an accident. Perform any

The door weatherstrips
necessary repairs before operating the vehicle.
The rubber hood bumpers
1998 -
MD-lsuzu
Parking Brake Inspection Engine Cooling System Service
Park on a fairly steep hill. Hold the vehicle with the Inspect the hoses and have them replaced if they
parking brake only. This procedure determines the are cracked, swollen or deteriorated. Inspect all
holding ability of the parking brake. pipes, fittings and clamps; replace as needed. Clean
Starter Switch Inspection the outside of the radiator and air conditioning
condenser. To help ensure proper operation, a
Caution: When you are doing this check, the
pressure test of the cooling system and pressure cap
vehicle could move suddenly. If It does, you or is recommended at least once a year.
others could be Injured. Follow the steps below.
Exhaust System Inspection
Follow this procedure for the starter switch
Be alert for any changes in the sound of the exhaust
inspection:
system or any smell of fumes. These conditions
1. Ensure that there is enough room around the indicate that the system may be leaking. Inspect or
vehicle. repair the exhaust system immediately, if needed.
2. Firmly apply the parking brake (refer to Parking Refer to Engine Exhaust and Running Your Engine
Brake in your Isuzu Owner's Manual if While You're Parked cautions in the Owner's manual.
necessary) and the regular brakes.
Windshield Wipers and Washers Inspection
Notice: Do not use the accelerator pedal, and Inspect the following:
be ready to turn off the engine immediately if Inspect the operation and the conditions of the
it starts.
wiper blades.
3. On automatic transmission vehicles, attempt to
Inspect the for wear or cracking.
start the engine in each gear. The starter
should function only in NEUTRAL (N) or PARK
Replace blade inserts that appear worn or
(P). If the starter functions in any other position, damaged or that streak or miss areas of the
perform the service of the vehicle. windshield.
On manual transmission vehicles, place the Defroster Inspection
shift lever in NEUTRAL (N). Push the clutch Move the control to the defrost symbol and the fan
down halfway and attempt to start the engine. to HI or the high symbol. Inspect the airflow from the
The starter should function only when the clutch ducts at the inside base of the windshield.
is pushed down all the way to the floor. If the
Mirrors and Sun Visors Inspection
starter functions when the clutch is NOT Verify that the friction joints hold the mirrors and the
pushed all the way down, perform the service
sun visor in place.
of the vehicle.
Seat Adjuster Inspection
Automatic Transmission Shift Indicator Inspection
Verify that the indicator points to the gear chosen. When adjusting a manual seat, ensure that the seat
adjuster latches by attempting to move the seat after
Steering Inspection latching.
Be alert for any of the following conditions:
in
Lamps Inspection

Changes steering action
Inspect the following lamps on the inside:

Abnormal front tire wear
The panel lighting

Changes in steering wheel position
The warning lights
An inspection or service is needed when the
following conditions occur:
The indicator lights

The steering wheel is harder to turn.
The interior lamps
The steering wheel has too much free play. Inspect the following lamps on the outside:

Strange sounds can be heard during turning or The license plate lamps
parking.
The sidemarker lamps
Brake System Inspection The reflectors or lights on the outside mirrors
Be alert for any of the following conditions: The headlamps
Illumination of the low air warning lamp

The parking lamps
The tone alarm
The identification lamps and the clearance

Changes in braking action
lamps
-
Repeated pulling to one side
The taillamps
-
Unusual sounds during braking The brake lamps
-
Increased brake pedal travel

The turn signals
Ensure that the air brake system reservoirs are
drained daily with full system air pressure. Inspect
The backup lamps
the system for leaks.
The hazard warning flashers
Any of these conditions may indicate the need for Inspect the headlamp aim if the beams seem to be
brake system inspection or service. inappropriately aimed.
1998 -
MD-lsuzu
Glass, Mirrors, Lamps and/or Reflectors At least every spring, flush these materials from the
Condition Inspection underbody using plain water. Thoroughly clean any
Inspect all glass, mirrors, lamps, or reflectors for the areas where mud and other debris may collect.
following conditions: Loosen the sediment packed in closed areas of the

Breaks frame before flushing.

Scratches Engine Cover Inspection
Verify that the cab's engine cover and seal (if
. Dirt
equipped) are not torn or damaged.

Damage Verify that the cover is bolted down firmly to
Any of the above conditions may reduce the view or the floor.
visibility or cause injury. Replace, clean, or repair
promptly if necessary. At Least Once a Year
Door Latches Inspection Key Lock Cylinders Service
Verify that the doors perform the following functions: Lubricate the key lock cylinders with the correct

Close lubricant. Refer to Fluid and Lubricant
Recommendations.
Latch
Underbody Flushing Service

Lock tightly At least every spring, use plain water to flush any
Inspect for broken, damaged, or missing parts that corrosive materials from the underbody. Take care to
might prevent tight latching. clean thoroughly any areas where mud and other
Cab Latches Inspection debris can collect.
Verify that the cab closes firmly.
Tractor Protection (Breakway) Valve Check
Inspect for broken, damaged, loose, or missing parts On air brake models, remove, disassemble, clean
that might prevent tight latching. and inspect the tractor protection (breakaway) valve.
Fluid Leaks Inspection Towing Vehicle Protection Valve
Inspect for fluid leaks of the following substances by On air brake models, remove, disassemble, clean,
looking at the surface beneath the vehicle after it and inspect the towing vehicle protection valve.
has been parked for a while:
Fuel

Coolant
Oil
Underbody Inspection
Corrosive materials used for ice and snow removal
and dust control may collect on the underbody. If
these materials are not removed, accelerated
corrosion (rust) may occur on the following
underbody parts:

The fuel lines
. The frame

The floor pan

The exhaust system
1998 -
MD-lsuzu
Owner Checks and Services (Single Axle)

Single Axle Models
290696
Legend
(1) Propshaft Slip Joint (16) Brake Camshaft Brake Caliper Rails
(2) Parking Brake Clevis Pin (If equipped with (If equipped)
hydraulic brakes only) (17) Slack Adjuster (Air Brakes Only)
(3) Clutch Release Cross Shaft (If equipped) (18) Brake Cam Roller Pins at interface of pin
(4) Master Cylinder (If equipped with hydraulic and shoe (Air Brakes Only)
brakes only) (19) Front Steering Knuckles
(5) Steering Tie Rod Ends (If equipped) (20) Front Wheel Bearings
(6) Steering Column U-Joints (21) Steering Tie Rod Ends (If equipped)
(7) Front Wheel Bearings (22) Clutch Release Cross Shaft (If equipped)
(8) Front Steering Knuckles (23) Clutch Release Bearing (If equipped)
(9) Brake Cam Roller Pins at interface of pin (24) Battery Terminal (Except "ST" type)
and shoe (Air Brakes Only) (25) Transmission
(10) Slack Adjuster (Air Brakes Only) (26) Parking Brake Bell Crank (If equipped with
(11) Brake Camshaft Brake Caliper Rails hydralic brakes only)
(If equipped) (27) Parking brake Lever Pivot (If equipped with
(12) Steering Column Slip Joint (If equipped) hydralic brakes only)
(13) Steering Drag Link Ends (28) Propshaft Slip Joint
(14) Pivot Points and Hinges (29) Propshaft Slip Joint
(15) Pivot Points and Hinges (30) Rear Wheel Bearing
(31) Brake Cam Roller Pins at interface of pin
and shoe (Air Brakes Only)
7998 -
MD-lsuzu
(32) Brake Camsaft Brake Caliper Rails (36) Slack Adjuster (Air Brakes Only)
(If equipped) (37) Brake Camshaft Brake Caliper Rails (If
(33) Slack Adjuster (Air Brakes Only) equipped)
(34) Rear Axle (38) Brake Cam Roller Pins at interface of pin
(35) Spring Slip Pads (If equipped with and shoe (Air Brakes Only)
Multi-leaf) (39) Rear Wheel Bearing
Explanation of Scheduled Services

The brake pedal for excessive free play or
travel (or every 6 months, whichever occurs
1. Replace the automatic transmission fluid and
first). Perform the service, if necessary.
the filter at 10 400 km (6,500 mi), 41 600 km
(26,000 mi) and then every 41 600 km Inspect the brakes more often if driving
(26,000 mi) thereafter. habits and conditions result in frequent
Inspect the automatic transmission fluid level at

braking.
each 10 400 km (6,500 mi) interval that does Important: The spring brake section of the
not call for a fluid change (or every month, actuator is NOT serviceable.
8. Inspect the hydraulic parking brake drum and
2. Replace the manual transmission fluid every the linings for wear or cracks. Inspect the
62 400 km (39,000 mi). linkage and the adjustment. Inspect the spring
Inspect the manual transmission fluid level at brake actuator and the pump for leaks.
each 10 400 km (6,500 mi) interval that does 9. Change the main oil filter and the partial oil
not call for a fluid change (or every 3 months, filter element.
10. Inspect the clutch pedal for free travel. Use the
3. This is an emission control service. following procedure:
4. This is a noise emission control device.
Press the pedal using your hand until

in the resistance is felt.
5. This service applies only to vehicles sold
United States.
Maintain free travel at 38-51 mm (1.5-2.0 in)
6. Inspect the fluid level in the following measured at the clutch pedal pad.
components:
Inspect the clutch pedal for free travel at
5 200 km (3,250 mi) and 10 400 km
The brake master cylinder. A low fluid level
in the brake master cylinder may indicate (6,500 mi) and then every 10 400 km
worn brake linings and should be inspected. (6,500 mi) thereafter.

The clutch master cylinder (if equipped) 11. Inspect the rear axle air shift motor for fluid
The power steering pump leaks. Use the following procedure:

The axle

Remove the plug in order to inspect the
fluid level.

The transmission

Inspect the air lines and the hoses for the
. The hydraulic spring parking brake pump following conditions:
(if equipped)
-
Proper hookup
7. Inspect the following brake components: -
Binding
The brake lines and the hoses. Inspect the

lines and the hoses for the following

-
Leaks
conditions:
Inspect the rear axle air shift motor at
5 200 km (3,250 mi) and 16 00 km
-
Proper hookup
(24,000 mi) and then every 40 000 km
- Binding
(24,000 mi) thereafter.
-
Leaks
12. Lubricate all the grease fittings in the front
-
Cracks suspension, the front axle, and the steering
- Chafing linkage.
The disc brake pads for wear Lubricate the suspension, the axle and the
The rotors for surface condition steering linkage more often when operating
under dusty or muddy conditions and in
The drum brake linings for wear or cracks
excessive off-road use.

The drums
DO NOT lubricate the kingpin bushings with air
The wheel cylinders
pressure equipment. Use a hand-held grease
. The piston heat shields and the boots gun in order to ensure complete purge and

Other brake parts eliminate sealer cap distortion.
1998 -
MD-lsuzu
Lubricate the following components: 16. Inspect the spring-to-axle U-bolts and the

The transmission and the shift linkage shackle bolts for the proper torque.

The hood latches and the hinges When the vehicle is new or when you have
replaced the parts, inspect and adjust the

The parking brake lever pivot
torque more often during the first 10 000 km

The clevis pins and the linkage (6,000 mi). Inspect the torque at 800 km

The disc brake caliper rails (500 mi) and 3 000 km (2,000 mi) after the
The clutch linkage and the release bearing (if parts are first used.
equipped) 17. In order to maintain the exhaust system

The propeller shaft slip joint integrity, replace the exhaust pipes whenever a

The universal joint new muffler is installed.

The brake camshaft bracket Inspect the complete exhaust system for the
following conditions. Perform any needed

The slack adjusters
repairs immediately.

The pedal shaft Broken parts

The clutch cross shaft
Damaged parts

The clutch pedal springs Missing parts
13. Inspect the steering the system for damaged, Out of position parts
loose or missing parts. Inspect for parts

Open seams
showing signs of wear or lack of lubrication.
Replace the parts as needed. . Holes
Inspect the following components:

Loose connections
The steering gear mounting bolts. Tighten if
Other conditions which may permit exhaust
necessary. fumes to seep into the driver compartment.

The pitman arm nut. Tighten if necessary. 18. Inspect all of the engine drive belts for cracks,
fraying, wear, and proper tension. Adjust or

The gear housing upper cover and the side
replace the belts as needed. Replace the belts
cover attaching bolts. Tighten if necessary.
at 83 200 km (52,000 mi) and every 83 200 km

The steering column mounting bolts. Tighten
(52,000 mi) thereafter.
if necessary.
19. Do not lubricate the accelerator and cruise

The cardan joint clamp bolts. Tighten if
control cables.
necessary.
Inspect the throttle linkage for the following
The power steering hoses, the tubes and the
fittings for leaks. Ensure that the hoses and conditions. Perform any needed repairs
immediately.
the lines are not twisted, kinked, or tightly
bent.

Damaged parts (including throttle return
springs)

The clips, the clamps, the supporting tubes,
and the hoses for proper location and Missing parts (including throttle return
secureness. springs)

The steering gear for leakage around the
Interference
pitman shaft and the housing. If leakage is Binding
evident (lubrication oozing out, not just an
20. With the engine OFF and below normal
oily film), repair the leak immediately.
operating temperature, verify that the
14. Inspect the front and rear suspension for thermostatically controlled engine cooling fan
damaged, loose or missing parts, or parts may be rotated by hand on viscous-operated
showing signs of wear or lack of lubrication. drives. Replace the components as needed.
Replace the parts as needed.
21. Inspect the shields and the underhood
15. Adjust the tire pressure as indicated in the insulation for damage or looseness. Adjust or
Isuzu Owner's Manual for optimum tire life. replace the components as needed.
Inspect the tires for excessive or abnormal 22. Lubricate the following components:
wear or damage. Inspect the wheels for
The brake caliper V-ways
damage. Replace the wheels and/or tires as The brake caliper retainer
needed.
The brake caliper retainer spring
1998 -
MD-lsuzu
23. Perform the following wheel bearing service: 30. Perform the following inspections, replacing the

Grease type: Clean, inspect and lubricate parts as needed:
using the proper wheel bearing grease at Inspect the following components for damage

designated intervals or whenever the hubs which may cause leakage:

are removed. Refer to Fluid and Lubricant -
The fuel tank
Recommendations. -
The fuel cap
Oil-filled type: Some wheel bearings require
-
The fuel lines
a rear axle lubricant. If you have the oil-filled
Inspect the fuel cap for proper sealing ability
hubs, use a lubricant identical to that used in

the rear axle. Lubricant change intervals are and damage.

the same for both the front and the rear
Inspect the fuel cap gasket for an even filter
axles. Maintain the oil level at the OIL neck imprint.
LEVEL mark between the change intervals.
31. Drain, flush, and refill the cooling system. Refer
Refer to Fluid and Lubricant to Fluid and Lubricant Recommendations.
Recommendations.
Inspect the hoses. Clean the radiator, the
24. Inspect the air intake system installation in
condenser, the pressure cap, and the neck.
order to ensure that the gaskets are seated Perform the cooling system pressure test and
properly and all of the hose connections,
the pressure cap test.
fasteners, and other components are tight.
32. Tighten the wheel stud nuts to the torque
For gasoline engines, ensure that the air
values indicated in the Isuzu Owner's Manual at
cleaner housing is properly seated, that the 160 km (100 mi), 800 km (500 mi) and
cover fits tightly and that the wing nut is tight. 1 600 km (1,000 mi), then every 1 600 km
Tighten the connections and the fasteners or (1,000 mi) thereafter.
replace the parts as needed.
33. Change the lubricant. Refer to Fluid and
25. Incorrect injection timing may result in increased Lubricant Recommendations.
exhaust emission or reduced engine output.
34. Repack the upper kingpin roller bearing.
Inspect the tip of the injector needle valve and
the injector ofifices for accumulation of carbon. Notice: The spring brake section of the rear
brake diaphragms are non-serviceable.
Remove any contamination with an injector
cleaning tool by thoroughly cleaning the inside 35. Perform the following air brake service:
and outside of the injector end.
Test the air lines for leaks.
26. Inspect all of the fuel lines connections on the Tighten the air line connections as
fuel injection pump and the injector. necessary.
27. Replace the air cleaner filter (or every
Replace the compressor filter.
24 months, whichever occurs first). Replace the
Inspect the air parking brake chamber for
filter more often when driving in dusty leaks and damage.
conditions. Ask your dealer for the proper Inspect the lines and the hoses for leaks,
replacement intervals for your driving conditions.
cracks, chafing, etc.
28. Adjust the valve lash. Incorrect valve clearance
Inspect all attachments for tightness, wear, or
will result in increased engine noise and
damage.
reduced engine output. Retorque the rocker
shaft bracket nuts before inspecting and 36. Clean and lubricate the air brake automatic
adjusting the valve clearance. The intake and slack adjuster. Inspect the pushrod travel and
exhaust valve clearance is 0.4 mm (0.016 in) the auto adjustment operation. Perform the air
for cold adjustment. brake automatic slack adjuster service, if
necessary.
29. Verify curb idle speed at 10 400 km (6,500 mi),
83 200 km (52,000 mi) and then every 37. Inspect the operation of the air brake chamber
83 200 km (52,000 mi) thereafter. If necessary, and the following components. Inspect for
perform the adjustment by turning the injection leaks.
pump governor low idle adjusting screw.
The mounting

The clamps

The air lines
1998 -
MD-lsuzu
Maintenance and Lubrication General Information
Inspect the operation of the trailer brake hand Inspections and Other Services
control valve. Lubricate the cam and the
The steering shaft is provided with a lubrication
follower. fitting. The lubricant type and service intervals are
Remove, disassemble, clean, and inspect the outlined in Fluid and Lubricant Recommendations. In
following air brake components. Replace any order to reach the top lower steering shaft lubrication
parts showing wear. Replace any rubber parts: fitting, use the following procedure:
The safety valve
The standard brake chamber
The quick release valve
The quick release/double check valve

combination
The parking brake control valve
The double check valve
The spring brake control valve
For Stud Wheels Only: Tighten the wheel stud
nuts to the specified torque values at 100 miles
(160 km), 500 miles (800 km) and 1,000 miles
(1,600 km) and thereafter.
For Hub Piloted Wheels Only: Tighten the
wheel stud nuts to the specified torque values
at 1,000 miles (1,600 km). Thereafter, tighten
them 1,000 miles (1,600 km) after each time the
wheel is removed.
228489
1. Push down the boot (2) in order to expose the

lubrication fitting.
2. Turn the steering wheel until the lubrication

fitting can be reached.
3. Turn the steering wheel in order to rotate the

lubrication fitting location.
1S98 -
MD-lsuzu
General Information Vibration Diagnosis and Correction 0-51
Vibration Diagnosis and Correction

Specifications
Wheel Specifications
All Wheels (Except Dual Wheel Applications)
Lateral 1.143 mm 0.045 in
Radial 1.015 mm 0.040 in
Dual Wheel Applications 2.3 mm 0.0938 in
On-Vehicle Hub Check 1.52 mm 0.06 in
One -
Piece Propeller Shaft Runout Propeller Shaft Balancing Weight Amounts
Application Metric English Correction, Total Weight Clamp Spread, Degrees
Front 1.016 mm 0.040 in 0.0 180
Center 1.27 mm 0.050 in 0.1 174
Rear 1.40 mm 0.055 in 0.2 169
0.3 163
Two -
Piece Propeller Shaft Runout 157
0.4
Application Metric English 151
0.5
Front 0.762 mm 0.030 in
0.6 145
Center 0.762 mm 0.030 in 139
0.7
Rear 0.889 mm 0.035 in
0.8 133
0.9 127
Three -
Piece Propeller Shaft Runout
1.0 120
1.1 113
Front 1.016 mm 0.040 in
1.2 106
Center 1.27 mm 0.050 in
1.3 99
Rear 1.40 mm 0.055 in
1.4 91
1.5 83
1.6 74
1.7 64
1.8 52
1.9 36
2.0 0
1998 -
MD-lsuzu
0-52 Vibration Diagnosis and Correction General Information
this same period, options such as air conditioning,
Diagnostic Information and
power steering, and have become more and more
Procedures popular. These types of options increase engine
load. They can also generate unwanted noise and
Systematic Approach
vibration.
During the last 10 to 15 years, vehicle design and
Customer perception of quality can be directly linked
engineering have dramatically changed because of to the presence or absence of unwanted noise and
increased fuel costs, decreased fuel supplies,
vibration. A technician's ability to quickly diagnose
Corporate Average Fuel Economy requirements, and repair a noise or vibration directly affects that
clean air legislation, foreign competition,
customer's loyalty to the dealership. Technicians who
crashworthiness, and rising customer expectations.
are capable of satisfying this need will be highly
Vehicle designs have evolved from full-frame
regarded and in great demand.
construction, utilizing multiple noise/vibration isolating
body mounts, to lighter unibody designs that transfer The intent of this section of the service manual is to
provide a systematic approach to vehicle vibration
noise and vibration much more readily.
diagnosis and correction. By using Strategy Based
General Motors has greatly reduced the use of
Diagnosis and troubleshooting philosophies covered
heavier and smoother running V8 engines, replacing in this section, technicians will be able to provide
them with lighter, more fuel-efficient engines. During effective and timely repairs.
Vibration Diagnosis
Engine Firing Frequencies

Any Engine First 6-Cylinder Third Order 8-Cylinder Fourth
Condition Engine Speed (RPM) Order(Hz) (Hz) Order(Hz)
500 8.3 24.9 33.2
750 12.5 37.5 50
Shake
1000 16.6 49.8 66.4
1500 25 75 100
2000 33.3 99.9 133.2
Roughness
2500 41.6 124.8 166.4
3000 50 150 200
Buzz 3500 58.3 174.9 233.2
4000 66.6 199.8 266.4
Engine Order Vibration Road Test

Engine Order L6 V890" Tire and Wheel Inspection
^2 Order Torque Single Cylinder Single Cylinder The tires on all new Medium Duty models have a
Sensitive Misfire Misfire tire rating molded on the sidewall. A replacement tire
1st Order should have the same rating.
Abnormal Abnormal
Imbalance
1.5 Order Torque - -
Sensitive
2nd Order Abnormal Abnormal
2nd Order Torque Bank-to-Bank
-
Sensitive EGR/Fuel Variance

3rd Order Torque
Normal -
Sensitive
4th Order Torque
-
Normal
Sensitive
1998 -
MD-lsuzu
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95607
Legend
(1) Hard Cornering, Under Inflation
(2) Excessive Toe on Non-Drive Axle
(3) Heavy Acceleration on Drive Axle,
Excessive Toe on Drive Axle, Over Inflation
This test should be performed for ALL vibration 4. Note the following readings where the
complaints unless the disturbance occurs only with disturbance occurs:
the vehicle at a standstill. . The vehicle speed, km/h (mph)
Inspect the tire and wheel assemblies for the
The engine speed (RPM)
following conditions:
The frequency (if possible)

Unusual wear such as cupping, flat spots, and
Following this test, perform the Neutral Coast-Down
heel-and-toe wear
Test and the Downshift Test.
(These conditions can cause tire growl, howl,
slapping noises, and vibrations throughout the
Neutral Coast-Down Test
vehicle.)
1. Observe the necessary safety precautions.

Proper inflation
Refer to Road Test Caution in Cautions and
Bulges in the sidewalls
Notices.
(Not to be confused with normal ply splices,
2. On a smooth level road, accelerate to a speed
commonly seen as indentations in the sidewall.) slightly higher than the speed at which the

Bent rim flanges vibration occurs.
Inspecting these characteristics of the tire and wheel
assemblies may lead to the cause of the vibration. 3. Shift the vehicle into NEUTRAL and coast down
through the vibration range.
At the very least, the inspection will provide
assurance that the vehicle is safe for road testing. Note if the vibration is present in NEUTRAL.
If the vibration still occurs in NEUTRAL, then the
Slow Acceleration Test vibration is definitely vehicle-speed sensitive. At this
This test will identify the engine-speed or point, the engine, the clutch disc (manual
vehicle-speed related conditions. Additional tests may transmission), the propeller shaft (located inside the
be necessary in order to determine in which category driveline support assembly), the transmission flex
the vibration belongs. plate (automatic transmission) and the torque
1. Observe the necessary safety precautions. converter have been eliminated as a cause.
Refer to Road Test Caution in Cautions and Depending on the symptoms or frequency, the repair
Notices. will concentrate on the tire and wheel assemblies,
On a smooth, level road, slowly accelerate up the transmission output shaft, the rear axle
2.
to highway speed. differential pinion, or the rear drive axle shafts.
3. Look for disturbances that match the customer's

description.
1998 -
MO-lsuzu
Downshift Test 6. Slowly increase the engine speed while looking

Observe the necessary safety precautions. for vibrations that match the customer's
1.
Refer to Road Test Caution in Cautions and description.
Notices. 7. Note the engine speed (rpm) and frequency
2. On smooth, level road, accelerate to the
a (if possible) at which the disturbance occurs.
speed at which the complaint vibration occurs. 8. Repeat steps 4, 6, and 7 in Reverse, if
Note the engine RPM. necessary.
3. Decelerate and safely downshift to the next
lower gear (from OVERDRIVE to DRIVE, or Additional Tests
from DRIVE to SECOND, etc.) You can perform one or more of the following tests
4. Operate the vehicle at the previous for unique vibration complaints such as those that
engine RPM. are torque/load sensitive, in addition to vehicle-speed
If the vibration returns at the same engine RPM, the or engine-speed sensitive:
engine, the clutch disc (manual transmission), the Steering Input Test
propeller shaft (located inside the driveline support Standing Start Acceleration Test
assembly), the transmission flex plate (automatic
transmission), or the torque converter are the most Steering Input Test
probable causes. You may repeat this test is still
This test is intended to determine how much the
smaller gears, and in NEUTRAL, in order to confirm
the results. wheel bearings and other suspension components
contribute to the vibration, especially those relating to
In some cases, a vibration may be sensitive to
noises such as growl, grinding, and roaring.
torque or engine load, as well as being related to a
specific engine (RPM) or vehicle (km/h / mph) speed. 1. Observe the necessary safety precautions.
These vibrations can be most difficult to diagnose, Refer to Road Test Caution in Cautions and
and require additional testing. Still, following a Notices.
systematic approach usually leads to pinpointing the
2. Drive through slow sweeping turns with the
problem. vehicle at the vibration speed (mph) in one
Neutral Run-Up Test direction, then in the other.
This test is designed to identify engine-speed related 3. If the vibration gets worse or goes away,
vibrations. Use this test when the customer inspect the following components as possible
complains of vibration at idle, or as a follow-up to causes of the vibration:
the downshift test. This test more than likely doesn't
The wheel bearings
apply when the complaint is vehicle-speed related
The hubs
only (appearing at the same vehicle speed
regardless of the engine speed). The tire tread
1. Observe the necessary safety precautions.
Standing Start Acceleration
Refer to Road Test Caution in Cautions
and Notices. (Launch Shudder) Test
The purpose of this test is to duplicate a vibration
2. Slowly increase the engine speed while looking
for disturbances that match the customer's called launch shudder. In some cases, a powertrain
complaint. mount or an exhaust ground-out may also be
suspected, depending on the symptoms.
3. Note at which engine speed (rpm) and
frequency (if possible) that the vibration occurs. 1. Observe the necessary safety precautions.
Refer to Road Test Caution in Cautions
Brake Torque Test and Notices.
This test is designed to identify engine-related
2. With the vehicle at a complete stop and in
vibrations that were not uncovered with the Neutral
gear, remove your foot from the brake pedal.
Run-Up Test. This test also works for vibrations that
are sensitive to the engine load or to the torque. 3. Accelerate to 48-64 km/h (30-40 mph) while
This test will more than likely not apply to looking for vibrations that match the customer's
vehicle-speed related only vibrations. description.
1. Observe the necessary safety precautions. Other possible causes of launch shudder include the
Refer to Road Test Caution in Cautions following conditions:
and Notices.
Incorrect trim height. Refer to the vehicle
2. Apply the parking brake. Body Builder.
3. Block the front wheels. A damaged propeller shaft.
4. Step firmly on the brake pedal.

Worn universal joins.
5. Place the vehicle in Drive. A ground-out

engine/transmission mount.
Faulty exhaust hangers and mounts.
1998 -
MD-lsuzu
Front Spring Shackle Inspection Test
301868
301887 Exceeding this clearance may result in wander,

shake, or shimmy and a slapping noise.
The lateral gap between the front spring eyes and or
shackle and the frame mounted spring hanger
brackets should be measured with a feeler gauge
and not exceed 1.016 mm (0.040 in). Thrust washers
should be used to bring the lateral gap within
tolerances.
301863
Ifa vehicle rides well on a smooth road surface and

a jolt or severe "slap-in-the back" occurs when
passing over highway irregularities, the shackle pins,
shock absorbers, cab mounts and fifth wheel should
be inspected and corrected as required.
1998 -
MD-lsuzu
Shackle Pin Inspection Test . Vibrations that make noise:

Apply grease to the front spring pin and shackle pin -
Boom
lubrication fittings (if equipped). As grease is applied, -
Moan and groan
it should come out evenly at each end of the pins.
-
Howl
If the assemblies accept grease readily and grease
Whine
comes out each end of the assemblies, it is a good
-
indicator they are actuating properly and not seized.

Vibrations That Can Be Felt
Another method of inspecting the front spring pins to
Shake
ensure that they are not seized requires placing
jacks under the frame rail at the front of the vehicle
and lifting the vehicle. If the spring pivots around the
front spring pin, and the shackle link position
changes in relation to the spring leaves on the
bottom and mounting bracket on the top, the
assemblies are activating properly.
If the shackle link position does not change, replace
the front spring pin and shackle pins as required.
Fifth Wheel Inspection Test
95608
The shake is a low frequency vibration, typically

5-20 Hz. The shake is sometimes seen in the
steering wheel, the seat, or the console. The best
description is the feeling from an out-of-round or
unbalanced tire. Customers may refer to shake in
one of the following terms:
.Shimmy
. Wobble
301892
Shudder
. Waddle
Rock the fifth wheel mounting plate manually up and
down to ensure that it pivots freely in the fifth wheel Hop

support bracket. If the fifth wheel mounting plate is Inmost cases, damage to or wear of the following
seized or the pivot bushings are worn, service as components is to blame for the shake:
required.
The tires
Classifying the Vibration The wheels
The next step after road testing the vehicle is to The brake rotors (vehicle-speed sensitive)
identify the frequency of the duplicated and abnormal The steering tie rod ends
vibration. Use the EVA in order to measure the
The suspension ball joints
frequency. If the EVA is not available, the frequency
The engine (engine-speed sensitive)
can be categorized into groups according to how the
vibration feels or sounds. The majority of vibrations Roughness
will fit into one of the following categories. Roughness is a vibration with a slightly higher
Vibrations that can be felt: frequency than the shake, usually 20-50 Hz.
Roughness is similar to the feeling you get from
-
Shake holding a jigsaw.
-
Roughness
-
Buzz
-
Tingling
1998 -
MD-lsuzu
Buzz Examples of similar noises include a bumble bee, or

Buzz is slightly higher in frequency: 50-100 Hz. A blowing air across the top of a soda bottle.
buzz is similar to the feel of an electric razor. You Examples of words to describe moan or drone are
may feel it in your hands through the steering wheel, humming, buzzing, resonance. Moan or drone may
in the feet through the floor, or in the seat. Inspect be accompanied by a perceptible buzzing vibration.
the following components for a possible cause: Inspect the following systems:

The exhaust system The powertrain mounts
The A/C compressor The exhaust system.
.
The engine Howl
Tingling Howl is a noise at mid-range frequency of
This is the highest frequency that can still be felt. 120-300 Hz. This sounds like the wind howling.
Tingling may sometimes produce a PINS AND Whine
NEEDLES sensation. Customers may say the Whine is prolonged, high-pitched sound in the
a
vibration puts their hands or feet TO SLEEP. 300-500 Hz range, and is usually related to the
meshing gears or gear noise. Similar sounds include
Vibrations That Make Noise mosquitoes, turbine engines, and vacuum cleaners.
Boom
Boom is a low frequency interior noise of 20-60 Hz. Matching Frequency to Component Speed
Sometimes the customer complains of a pressure in At this point in the diagnosis, the vibration has been
their ears. Examples of similar noises include a duplicated, designated as abnormal, identified as
bowling ball rolling down an alley, deep thunder, or a being related to engine speed or vehicle speed, and
bass drum. assigned a frequency from the EVA or categorized
A customer may use the following words to into a symptom group based on how it feels or
describe boom: sounds.
. Droning Automotive vibrations are usually related to the
rotating speed of a component. The speed of these
Growling
components will be calculated using either an engine

Moaning speed or vehicle speed method. The engine rpm
Roaring readings taken during the road test will be used in
diagnosing vibrations that are engine speed
Rumbling
sensitive. If the vibration is vehicle speed sensitive,

Humming the rotational speed of the tires needs to be
Boom may not be accompanied by a perceptible determined. As long as the vehicle is operated at a
vibration (roughness). constant speed, the tires will operate at a constant
Moan or Drone speed. These speed is measured in rotations or
Moan or drone is a sustained tone at a low cycles per second. The reading is then compared to
frequency of 60-120 Hz, somewhat higher the frequency of the vibration, which is also
than boom. measured in cycles per second.
1998 -
MD-lsuzu
Calculating Tire Rotation
TIRE/WHEEL AhsID PROPSHAFT ROTATION
Vehicle Information
km/h
Complaint Speed' (mph) Year: Undal:
Symptom: VIM:
Frequency: Enqine: Trans:
Engine Speed: mm Tire Siza: Axle Ratio:
Gear: TPC Soec:
Tire/Wheel Speed
Vibration km/h t 8(km/h) Increments of

Occurs at: mph * 5(mph) 8 km/h (5mph)
Tire/Wheel Speed,
tire RPS'
8 km/h (5mph) RPS (Hz)
x atSkm/h ^
increments 1st order
(5mph)
(from chart)
1st order
x2 2nd order
1st order
x3 3rd order
Propeller Sh aft Speed

Propeller Shaft Speed
1st order
tire x 1st order
(axle ratio)
1st order
props haft x2 2nd order
'UPS- revolutions per awcond; equates to cc'/ck par secand (Hz).
6509
Determine the rotational speed of the tires in 4. Divide the tires rolling circumference by 88.
revolutions per second, or Hertz (Hz), based on the
5. Multiply the Hertz value by the number of
vehicle speed at which the vibration occurs. In order 8 km/h (5 mph) increments.
to determine the rotational speed, follow this
6. The result is the rotational speed of the tires in
procedure:
Hertz at the complaint speed. If this figure
1. Determine the complaint speed the vehicle
matches the vibration frequency, a first-order

speed at which the vibration occurs. vibration is present in the tire and wheel
2. Determine the number of 8 km/h (5 mph) assembly.
increments: Sometimes, the tire/wheel vibration may be of
Divide the complaint speed by 8 when a higher-order. In order to compute possible
using km/h. higher-order vibrations, multiply the rotational speed
Divide the complaint speed by 5 when of the tires in Hertz at the complaint speed by the
using mph. order number. If any of these matches the vibration
frequency, then a vibration of that particular order is
3. Measure the tires rolling circumference. present in one of the tire and wheel assemblies.
1998
MD-lsuzu
Steering and Suspension Assembly Vibrations or shake, usually felt in the steering wheel or in the
Steering and suspension assembly vibrations are the seat. Inspect the following components for wear or
first level of testing for low-frequency vibrations that damage:
are vehicle-speed sensitive. The symptoms if a The steering tie rod ends.
steering/suspension first-order vibration are shimmy
The suspension ball joints.
Tire and Wheel Vibration

Problem Possible Cause Correction
Wheel Hop, Vehicle Rocks and debris wedged between dual disc Remove the rocks and debris.
Vibration, and Rough wheels
Steering
An out-of-balance tire and/or hub and Determine the out-of-balance component.
drum/rotor assembly Balance the component or replace the
component.
Loose or worn driveline or suspension Identify the location of the vibration. Vibration
components may be transmitted through the frame, so that a
rear end vibration gives the impression of

coming from the front. Repair or replace the
loose or worn components.
Wobble, Vehicle A bent or distorted disc from overloading or Replace the wheel.
Vibration, and Rough improper handling
Steering
Loose mountings Replace the worn or damaged components.

Damaged studs or wheel nuts

Enlarged stud holes
A worn or a broken hub face
Foreign material on the mounting surfaces
Improper alignment Align the wheels. Refer to Wheel Alignment

Specifications in Wheel Alignment.
Loose, worn, or broken suspension components Repair the components or replace the
components.
Tire and Wheel Runout Measurement

J34481
Aluminum Disc-type Wheels J8001
Tools Required
J 8001 Dial Indicator Set
J 34481 Universal Flexible Magnetic Dial
Indicator Stand
1. Inspect the torque of the wheel nuts.
2. Inspect the rim-to-drum or the rim-to-hub mating

surfaces. Verify that the surfaces are clean and
free of distortions and corrosion.
3. Remove the tire-wheel assembly. Refer to
Wheel Removal (Front) or Wheel Removal
(Dual/Rear) in Tires and Wheels.
4. Remove the tire from the wheel. Refer to Tire
Mounting and Dismounting in Tires and Wheels.
5. Clean the rim-to-hub or the rim-to-drum mating

surface and install the rim. Refer to Wheel
209841
Installation (Front) or Wheel Installation
(Dual/Rear) in Tires and Wheels. 6. Position J 34487 so that J 8001 contacts the
rim surface.
1998 -
MD-lsuzu
7. Measure the wheel lateral runout using J 8001 12. Position J 34481 so that J 8001 contacts the
while gently turning the rim. tire surface.
Reading 13. Measure the total radial runout using J 8001
The lateral runout at the rim should not exceed while gently turning the wheel.
3.1 mm (0.125 in). If the rim exceeds this Reading
measurement, replace the rim. The radial runout at the rim should not exceed
3.1 mm (0.125 in).
14. If the wheel exceeds this measurement,
demount the wheel. Clean the rim-to-tire mating
surfaces and mount the wheel to the rim. Refer
to Tire Mounting and Dismounting in Tires and
Wheels. Return to the previous step and
recheck the runout.
Off-Vehicle Hub and Wheel Check
209842
8. Position J 34481 so that J 8001 contacts the

rim surface.
9. Measure the wheel radial runout using J 8001

while gently turning the rim.
Reading
The radial runout at the rim should not exceed
3.1 mm (0.125 in). If the rim exceeds this
measurement, replace the rim. 209843
1. Place a straightedge on the face or the hub of

the wheel.
2. Measure the distance from the straightedge (1)
to the edge of the rim (2) at four equally
spaced locations. If the distance (3) is the
same at all positions, then the wheel is not
distorted.
You may also check a dismounted wheel for
radial and lateral runout. Temporarily mount the
wheel to a hub on the vehicle. Follow the
procedure for the On-Vehicle Check.
On-Vehicle Hub Check

If you are not certain whether the wheel or the hub
is distorted, check the hub using the following
procedure:
1. Replace the existing wheel with a wheel known
to be good.
2. Turn the wheel and perform the same
209840
measurements shown in the previous
10. Mount the tire to the wheel. Refer to Tire procedure.
Mounting and Dismounting in Tires and Wheels.
3. If the measurements are within the limits of
11. Install the tire-wheel assembly. Refer to Wheel
2.3 mm (0.0938 in) laterally and radially, then
Installation (Front) or Wheel Installation the wheel is good, but the hub is sprung.
(Dual/Rear) in Tires and Wheels.
1998 -
MD-lsuzu
Steel Disc-type Wheels

Tools Required
J 34481 Universal Flexible Magnetic Dial
Indicator Stand
1. Inspect the torque of the wheel nuts.
2. Inspect the rim-to-drum or the rim-to-hub mating

surfaces. Verify that the surfaces are clean and
free of distortions and corrosion.
3. Raise and support the axle on the side that you

are preparing to inspect.
209838
7. Position J 34487 so that J 8007 contacts the

tire surface.
8. Measure the total lateral runout using J 8007

while gently turning the wheel.
Reading
The lateral runout at the rim should not
exceed 3.1 mm (0.125 in) for single
wheels.

exceed 4.7 mm (0.187 in) for dual wheels.
9. If the wheel exceeds this measurement,
demount the wheel. Clean the rim-to-tire mating
209835
surfaces and mount the wheel to the rim. Refer
4. Position J 34401 so that J 8001 contacts the to Tire Mounting and Dismounting in Tires and
rim surface. Wheels. Return to the previous step and
recheck the runout.
5. Measure the wheel lateral runout using J 8001
while gently turning the rim.
Reading

exceed 3.1 mm (0.125 in) for single
wheels.
.
exceed 4.7 mm (0.187 in) for dual wheels.
6. If the rim exceeds this measurement, replace
the rim.
209839
10. Position J 34487 so that J8007 contacts the

rim surface.
1998 -
MO-lsuzu
11. Measure the wheel radial runout using J 8001 Off-Vehicle Hub and Wheel Check
while gently turning the wheel.
Reading
The radial runout at the rim should not exceed
3.1 mm (0.125 in). If the rim exceeds this
measurement, replace the rim.
209843
1. Place a straightedge on the face or the hub of

the wheel.
2. Measure the distance from the straightedge (1)
to the edge of the rim (2) at four equally
209840 spaced locations. If the distance (3) is the
12. Position J 34481 so that J 8001 contacts the same at all positions, then the wheel is not
tire surface. distorted. You may also check a dismounted
13. Measure the total radial runout using J 8001 wheel for radial and lateral runout. Temporarily
while gently turning the wheel. mount the wheel to a hub on the vehicle.
Follow the procedure for the On-Vehicle Check
Reading
The radial runout at the rim should not exceed On-Vehicle Hub Check
3.1 mm (0.125 in). If you are not certain whether the wheel or the hub
14. If the wheel exceeds this measurement, is distorted, check the hub using the following
demount the wheel. Clean the rim-to-tire mating procedure:
surfaces and mount the wheel to the rim. Refer 1. Replace the existing wheel with a wheel known
to Tire Mounting and Dismounting in Tires and to be good.
Wheels. Return to the previous step and
2. Turn the wheel and perform the same
recheck the runout. if runout is excessive,
measurements shown in the previous
replace the rim.
procedure.
3. If the measurements are within the limits of
2.3 mm (0.0938 in) laterally and radially, then
the wheel is good, but the hub is sprung.
1998 -
MD-lsuzu
Driveline Vibration Analysis with EVA The "roughness" or "buzz" vibration is felt in
the seat, floor or steering wheel.
The corresponding frequency on the EVA
equals first-order driveline rotation (25-60 Hz),
depending on the speed of the vehicle and the
ratio of the axle. Refer to the worksheet in
order to obtain the rotation speed of the
propeller shaft.
Driveline Vibration Analysis

Once you identify a vibration that is related to the
driveline, continue testing in this service area. The
following components are possible sources of
first-order driveline vibration:
The propeller shafts

The transmission output shaft

The pinion flange

The pinion gear
Locate the Source of Driveline Vibration with

301903
the EVA
The following components are possible sources of Caution: Never run the vehicle faster than
driveline vibration: 112 km/h (70 mph) when performing propeller
shaft vibration or checking for balance. Stay
The transmission output shaft
clear of rotating components and balance

The propeller shaft/s (driveshaft/s) weights to avoid personal injury. Do not run the

The union flange vehicle on the hoist for extended periods of time
The pinion gear to avoid engine or transmission overheating. Do
not step on the brake pedal with the brake drums
The above components are either bolted or splined
removed.
together. Therefore, all of the components rotate at
the same speed, vibrate at the same frequency and In order to pinpoint the source of vibration,
have the same symptoms. reproduce the vibration with the vehicle in the
Driveline vibrations may relate either to the first or to service stall. Then determine which component is
vibrating the most using the EVA and the following
the second order of driveline rotation. Driveline
vibrations are always related to the speed of the procedure:
vehicle. The vibration is often related to torque. If the 1. Raise the vehicle to curb height. Support the
vibration is worse or only noticeable when vehicle on a hoist or on safety stands. Do not
accelerating, decelerating, or crowding the throttle, allow the axle to hang. Refer to Lifting and
then the vibration is related to the torque. The Jacking the Vehicle in General Information.
vibration will always occur at the same speed. If a 2. Remove the rear tire/wheel assemblies. Refer
vibration is both torque and speed sensitive, the to Wheel Removal (Front) in Tires and Wheels.
driveline is the probable cause. Tire/wheel vibrations
3. Remove the brake drums. Refer to Brake Shoe
are speed sensitive, but not torque sensitive. Replacement in Air Drums.
First-Order Driveline Vibration Symptoms 4. Ensure that the propeller shaft is free of
The following symptoms may indicate first-order undercoating.
driveline vibration: 5. Inspect the propeller shaft and U-joints for
The vibration is related to vehicle speed. dents or damage.

The vibration is torque sensitive. 6. Start the engine.
A "boom" or "moan" noise is present. 7. Place the transmission in gear.
The vibration occurs commonly above 8. Run the vehicle at the speed which the
72 km/h (45 mph), but possibly as low as vibration occurs.
48 km/h (30 mph).
1998 -
MD-lsuzu
The EVA is able to simplify the balancing process.

Use the following procedure:
1. Use the EVA in order to determine which end
of the propeller shaft has the most vibration.
2. Mark the end of the propeller shaft (1) that has

the most vibration at four points (2), 90 degrees
apart. Number the marks 1 through 4.
3. Mount the EVA sensor onto the bottom of the
following components:
.
The differential housing
The center bearing support (for two-part
propeller shafts)

The transmission tailshaft assembly
4. Position the sensor as close to the propeller
shaft as possible. Ensure that the UP side of
the sensor faces up. Ensure that the sensor
is horizontal.
Notice: Do not use cruise control to maintain

176032
vehicle speed.
Hold the EVA sensor against the pinion nose and
5. Start the engine.
the transmission tailshaft assembly in order to
determine which end of the propeller shaft has the 6. Turn off all engine accessories.
most vibration. The end that has the most vibration 7. Place the transmission in gear.
will have a higher amplitude on the EVA.
8. Run the vehicle at the speed which causes the
If the vehicle has a two-piece propeller shaft, inspect most vibration in the propeller shaft.
the center support bearing.
9. Hook the timing light clip to the trigger wire.
If the transmission tailshaft vibrates, inspect the
10. Plug the vibration sensor into Input A of the
transmission crossmember under the transmission EVA. Input B does not have strobe light
mount. If the mount is secured properly, there should capability.
be no vibration at the crossmember.
11. Verify that the predominant frequency on the
Runout and Balance Testing with the EVA EVA display matches the frequency of the
original vibration. Use the strobe light only if the
rotation speed of the propeller shaft is the
predominant frequency.
12. The EVA displays a series of questions in order
to select the correct filter. Press YES in order
to select the desired filter. Ensure that the
frequency is in the middle of the filter range.
Use the full range only as a last resort.
13. The EVA displays the test frequency, the
amplitude and the filter range. The driveline is
balanced when the amplitude is near two. In
some cases a slightly higher amplitude will
provide adequate balance.
14. Point the timing light at the propeller shaft. The
strobe effect will appear to freeze the propeller
shaft. Note which of the numbered marks is at
the bottom of the propeller shaft (the 6 o'clock
position). This position is the light spot.
15. Turn the engine off.
182137 16. Install a weight directly on the light spot.
Ensure that the runout of the various driveline 17. Start the engine.
components are within specifications. If the runouts 18. Run the vehicle at peak vibration speed.
are within specifications, strobe balance the driveline. 19. Strobe the propeller shaft again.
1998 -
MD-lsuzu
The propeller shaft is balanced if the strobe image is If three weights fail to balance the driveline, replace
erratic and the amplitude is near two. the propeller shaft.
The propeller shaft is not balanced if one of the When the propeller shaft balances, road test the
following conditions exist: vehicle in order to verify that the vibration is
The weight and the original light spot are at eliminated.
the 6 o'clock position
This condition means
that there is not enough weight on the
First-Order Driveline Vibration Analysis
propeller shaft.
(Torque Sensitive)
If the vehicle has a vibration that is equal to
In order to correct the balance, add a second
weight next to the first weight. Inspect the first-order driveline rotation, and the vibration is not
balance again using the strobe light. present when testing the vehicle in the stall, then
internal rear axle components are the probable
cause of the vibration.
Internal rear axle components are also the probable
cause of the vibration if you were able to correct the
vibration in the stall, but the vibration returned during
the road test. Internal rear axle vibrations may be
aggravated by the load of the vehicle working
against the ring and pinion gear seat.
Since the propeller shaft and the pinion gear are
bolted together through the pinion flange, the
propeller shaft and the pinion gear operate at the
same speed. Vibration in the pinion gear will
therefore have the same frequency and symptoms
as the propeller shaft.
0.0 1.0 2.0 In order to isolate the vibration to the pinion gear,
use the following procedure:
1. Raise the vehicle to curb height. Support the
vehicle on a hoist or on safety stands. Refer to
Lifting and Jacking the Vehicle in General
Information.
182176
If the weights are now between 90 and 2. Remove the tire/wheel assemblies. Refer to
Wheel Removal (Front) in Tires and Wheels.
180 degrees off (between the 9 and the
3 o'clock positions) there is too much weight. 3. Remove the brake drums. Refer to Brake Shoe
In order to correct the balance, split the two Replacement in Air Drums.
weights equally on either side of the original 4. Touch the pinion nose, or hold the EVA
light spot. Splitting the weight will produce a vibration sensor up to the pinion nose.
total weight between one and two weights.
5. Use another technician in order to accelerate
Inspect the balance again using the strobe light. and decelerate the vehicle through the speed
Adjust the weights as necessary. range at which the vibration was noticed during
The weight and original light spot are 90 to the road test.
180 degrees off (between the 9 and the Example
3 o'clock positions)
This condition means
If the vibration was originally noticed at
that one weight is too much.
88 km/h (55 mph), accelerate from
In order to correct the balance, split the two
72 km/h (45 mph) to 107 km/h (65 mph).
weights equally on either side of the original Then decelerate from 107 km/h (65 mph)
light spot. in order to produce a total weight back to 72 km/h (45 mph).
less than one (between 120 and 180 degrees

Repeat the above step and note whether or
apart).
not the pinion nose vibrates under load
Inspect the balance again using the strobe light.
during acceleration and/or deceleration.
Adjust the weights as necessary.
If the vibration does not occur during the above
The weight and the original light spot are within procedure, install the brake drums and the tire/wheel
180 degrees of the 6 o'clock position. assemblies. The brake drums and tire/wheel
Move weight towards the 6 o'clock position. assemblies will add additional load on the system.
Inspect the balance again using the strobe light. Then repeat the above test.
Adjust the weight as necessary. Refer to the
Ensure that both axle shafts rotate at the same
previous two conditions.
speed. The differential may mask a vibration when
If the shaft will not balance using two weights, then
one tire is spinning faster than the other tire.
place a third weight on the light spot. Split the first Adjust the brakes in order to correct unequal tire
two weights in order to produce a total weight rotation speed.
between two and three weights.
1998 -
MD-lsuzu
If you are unable to reproduce the vibration in the Second-order driveline vibrations are independent of
stall, apply the brake lightly in order to load the runout or balance of a driveline component.
system further. Maintain the vehicle speed at The following description of basic U-joint theory will
which the vibration was noticed. Do not overheat help you to understand where second-order driveline
the brakes. vibrations originate and why they occur.
If the pinion nose vibrates under acceleration and/or As the propeller shaft rotates, the U-joints
deceleration, and the other driveline components are speed up and slow down twice for each rotation
eliminated as the cause of the vibration, then one of of the propeller shaft.
the following conditions may cause the vibration:
The acceleration and deceleration of the
A high spot on the pinion gear U-joints is not visible. If there is vibration in the
. A bent pinion stem U-joints, the acceleration and deceleration will
A cocked pinion bearing be audible and tactile.
An improper axle housing bore

Compare the U-joint in a vehicle to a
Anything that effects the pinion gear and how the universal-type socket. When a universal-type
pinion gear contacts the rotating ring gear may socket is used to tighten a bolt, the socket will
"bind and release" as the socket turns toward
contribute to a first-order, torque-sensitive driveline
90 degrees. The "bind and release" occurs
vibration. The only way to correct the condition is to
twice for each revolution of the socket.
replace the faulty components. In most cases, the
ring and pinion gear set and the related bearings The U-joint in a vehicle works in the same way
must be replaced. In some case, however, the axle as the universal-type socket. The "bind and
housing must be replaced. Complete a close-up release" effect is directly proportional to the
visual inspection for damage or unusual wear in angle that the U-joint operates: the greater the
order to measure or identify the specific faulty angle, the greater the effect.
component.
Because the transmission output speed is
It is possible to isolate an internal axle vibration. constant, the binding and releasing of the
Install a "known good" axle assembly from a stock U-joints is better described as an acceleration
unit. Verify that the "known good" axle assembly and deceleration which occurs twice for each
does not have a vibration problem. revolution of the propeller shaft.
If the propeller shaft is running slowly, the
Once you correct the internal axle problem, road test
the vehicle. Inspect the vehicle for vibration. Balance accelerating and decelerating effect is visible.
the driveline as necessary in order to eliminate any The acceleration and deceleration may create a
remaining vibration. vibration due to the fluctuations in force that

are generated at high speeds.
Second-Order Driveline Vibration Theory
Canceled Out Driveline Angles
182178
182180
A faulty universal joint (U-joint) may cause a
Legend
vibration that occurs twice for each rotation of the
(1) Front Working Angle
propeller shaft. This type of vibration is called a
second-order vibration. (2) Rear Working Angle
1998 -
MD-lsuzu
increases. Launch shudder feels more like driveline

roughness at higher speeds 24-40 km/h (15-25 mph).
At speeds greater than 40 km/h (25 mph) the
vibration usually disappears.
Launch shudder vibration is equal to a second-order
vibration of the driveline. The EVA will not perceive
frequency information due to the transitory nature of
ZJ11
^ launch shudder.
lnl
fll^^ Engine Related Vibration
Engine vibration is usually due to one or more of the
following conditions:

First-order engine imbalance
.
Inherent engine firing sequence

Inherent shaking engine forces

Engine-driven accessories
Because these vibrations are engine-speed related,
301902 they are also normally torque sensitive. These
vibrations may appear and disappear at different
Engineers design drivelines in order to compensate
for the accelerations and decelerations in order to vehicle or road speeds, but will always appear at the
produce a smooth, constant flow of power, as same engine speed.
listed below: For example, if a customer states that a vibration is

The transmission drives the front yoke of the present at 40 km/h (25 mph), 64 km/h (40 mph), and
propeller shaft at a smooth and constant speed. again at 104 km/h (65 mph), and that the symptoms
The first U-joint causes the power to fluctuate of the vibration are similar at all of these speeds, the
twice for each revolution of the propeller shaft. vibration is probably engine-speed related. Any
disturbance or vibration that is present during the

The second U-joint, oriented 90 degrees from
following road tests would be considered
the first U-joint, causes the power to fluctuate
opposite that of the first U-joint. engine-speed related:
.
As the first joint slows down, the second joint
The Neutral run-up test
speeds up. The downshift test
This design causes one U-joint to cancel out the The brake torque test
effect of the other U-joint. The cancelled effects
Any vibration that is present during the Neutral
result in a smooth, constant power flow from the
Coast-Down test is not engine-speed related. The
output yoke of the propeller shaft.
engine-related vibrations covered in this diagnosis
Second-order driveline vibrations occur when the are engine-speed sensitive only.
cancellation become unequal between the front and
rear U-joints. Notice: Do not accelerate against the brakes for
longer than 10 seconds. Do not overheat the engine
Second-Order Driveline Vibration Symptoms or the transmission. Depending on the vehicle
Second-Order driveline vibration has the following design, the engine will only accelerate to a certain
signs and symptoms: point under these conditions. Also, care should be
taken during diagnosis as some disturbances may

The vibration is always related to
be created during brake torque that normally do
vehicle speed.
not exist.
The vibration is usually torque-sensitive.
is Notice: Proper flywheel installation requires carefully
.
The vibration
worse under a torque load.
WALKING the flywheel onto the crankshaft and
Launch shudder is the most common complaint of a
stagger-tightening the bolts. Proper torque converter
second-order driveline vibration.
to flywheel installation then requires gradually
Launch shudder occurs during acceleration from WALKING the torque converter to be flush with the
0-40 km/h (0-25 mph). Launch shudder appears as a flywheel, prior to installing the bolts. Do not draw the
low frequency shake, wobble, or shudder. The driver
torque converter to the flywheel with the bolts. If
may feel the vibrations in the seat or steering wheel
these precautions are not followed, warping or
at low speeds 0-24 km/h (0-15 mph). The vibrations
will increase in frequency as the vehicle speed bending of the flywheel and/or damage to the
transmission torque converter may result.
1998 -
MD-lsuzu
First-Order Engine Imbalance
95610
Engine imbalance is a condition that exists when a 6. Disconnect the torque converter from the
component that rotates at crankshaft speed is either flywheel. Move and secure the torque converter
unbalanced or has excessive runout. In rare cases, away from the flywheel.
the crankshaft may be unbalanced. In any case,
7. Perform the Neutral run-up test again. Refer to
balancing the component or correcting the runout
Road Test in Vibration Diagnosis and
may bring the disturbance to an acceptable level. Correction. If the flywheel shows any wobble or
Symptoms lateral runout, replace the flywheel. Refer to
The following list contains symptoms that are Refer to Engine Flywheel Replacement in
8.
typically exhibited from a first-order engine Engine Mechanical 7.8L.

imbalance.
9. Rotate and secure the torque converter to the
Vehicle shake at low engine speeds of flywheel 120 degrees from its originally marked
500-1200 RPM, or 8-20 Hz position and perform the Neutral run-up test.

Roughness and BOOM at higher speeds of 10. Repeat Step 7 with the torque converter in all
1200-3000 RPM, or 20-50 Hz three positions until the vibration is minimized.
Vibration detected during the Neutral run-up test If the vibration still exists, replace the torque
11.
Isolating the Components converter.
Inspect the following:
12. If the vibration still exists after replacing the
1. Inspect for any exhaust system binding or torque converter, replacing the harmonic
exhaust-to-vehicle contact. Repair as necessary. balancer MAY reduce the vibration.
Refer to Vibration or Rattling in Engine 13. If the vibration still exists after replacing the
Exhaust. crankshaft balancer, the problem is related to
2. Inspect all engine and transmission mounts. residual engine imbalance.
Repair or replace as needed. Correcting Residual Engine Imbalance
3. Refer to Engine Mount Inspection in Engine 1. Install washers on the harmonic balancer
Mechanical
7.8L. pulley bolts.

4. Perform the Neutral run-up test noting the 2. Replace bolts with longer bolts of equal
severity and the RPM at which the vibration is
hardness as needed.
the worst. Refer to Road Test in Vibration
Diagnosis and Correction 3. Manual Transmission Only: Inspect the flywheel
and the pressure plate for the following
5. Matchmark the torque converter and the conditions:
flywheel.

Correct factory indexing.

Warping

Balance
1998 -
MD-lsuzu
Excessive Inherent Engine Firing Frequency 4. Slowly accelerate until the vibration occurs.
Firing frequency is a term used to describe the
5. Note the vehicle and engine speed (RPM)
pulses created as the engine fires each cylinder. All where the disturbance occurs.
engines have a firing frequency. However, the object
is to keep these disturbances from entering the 6. Press ENTER on the EVA in order to record
the vibration data.
passenger compartment. Perform the following steps:

Ensure that the engine and the exhaust system 7. Perform the road test diagnoses in order to
determine engine-speed or vehicle-speed
are mounted in a relaxed position.
sensitivity. Refer to Road Test in Vibration

Ensure that all of the engine mounts, Diagnosis and Correction.
transmission mounts and exhaust hangers are
in good condition and correct for the Engine Firing Frequency Symptoms
application. .The vibration may be torque sensitive.

Ensure that no hoses or lines are contacting The vibration is engine-speed related.
the frame or the body.
The vibration is heard as a boom or a moan.
The frequency of these disturbances will depend on
The vibration is felt as shake, roughness, or
the number of cylinders. The engine order will buzz (depending on the number of cylinders).
always be equal to one-half the number of cylinders.
The vibration excites the resonance of a system
This is because a four-stroke engine requires two
or a component, causing the system or the
complete revolutions of the crankshaft in order to fire
all of the cylinders. component to have a narrow engine speed
(RPM) range.
For example, a V6 engine will fire cylinders 1, 3 and Correct these types of complaints by isolating
5 on the first revolution. Cylinders
2, 4 and 6 will fire the vibration from the passenger compartment or
on the second revolution. This results in three firing the body.
pulses per revolution of the crankshaft, or third order.
A V8 engine will fire cylinders 1, 3, 5, and 7 on the Diagnosis and Repair of Engine Firing
first revolution. Cylinders 2, 4, 6, and 8 will fire on Frequency-Related Vibrations
the second revolution. This results in four firing 1. Raise and suitably support the vehicle. Refer to
pulses per revolution of the crankshaft, or Lifting and Jacking the Vehicle in General
fourth order. Information.
Engine Vibration Diagnosis with the EVA 2. Take the necessary safety precautions. Refer to
Work Stall Test Caution in Cautions and
Notices.
3. Attempt to duplicate the vibration.
INPUT A INPUT B
4. While the vibration is present, find the area(s)
of the vehicle excited by the vibration.
5. Inspect for witness marks due to a rubbing

IW2X<^ component.
6. Isolate the component and re-evaluate the
vibration.
r'TaT'ljii-N^Hpmrrniin 7. Inspect for proper torque on the excited
TMFir component(s). Tighten the component fasteners
as needed.
8. If the vibration still exists, proceed to the
following diagnostic information.
Engine Firing Frequency-Related Vibration
Causing Components
Important: Some residual vibrations may be normal.
Compare the complaint vibration with a similar
95611 vehicle to validate that the vibration is abnormal,
preferably with the customer present. Also, refer to
1. Place the EVA vibration sensor on the seat bulletins for updates on the use of mass damper
track rail with the UP label facing upward.
weights for specific applications.
2. Plug the EVA into a 12-volt power supply.
1. Inspect and replace any collapsed engine
3. Prepare the EVA for data recording: mounts.
3.1. Press RECORD.
2. Refer to Engine Mount Inspection in Engine
3.2. Select a snapshot tag number. Mechanical
7.8L.
3.3. Press ENTER in order to begin
recording.
1998 -
MD-lsuzu
3. Inspect the exhaust system and hangers. Engine-Driven Accessories

Remember that exhaust systems can expand
one to two inches in length when they are hot.

Remove the exhaust system hangers one at
time.
a
Adjust or replace any faulty exhaust system

hangers as needed.
4. Lubricate the exhaust manifold flexible coupling.
5. Inspect the air conditioning and power
steering lines.

Isolate the hoses from the body.
Install the retainers.
6. Inspect the drive belts for whipping.

7. Inspect the accessory unit fasteners for damage
or looseness. Tighten or replace as necessary.
8. Inspect the body panels for missing or
loose welds.
9. Remove any aftermarket equipment that may
complete a vibration transfer path into the
95613
passenger compartment.
10. Inspect the exhaust system and powertrain Important: Some vibrations may be normal.
Compare the complaint vibration with a similar
mounts. Re-bed the engine and align the
exhaust system as follows if needed: vehicle that is operating normally to validate that the
vibration is abnormal, preferably with the customer

Loosen the exhaust system and powertrain
present.
mounts and hangers.
Diagnosing engine driven accessories that exhibit
Tighten all fasteners with the powertrain in
vibration pose some special challenges. For
the relaxed position.
example, most engine accessory drive belts can no
Inherent Engine Shaking Forces longer be removed one at a time in order to isolate
Just like firing frequency, some engine disturbances the condition. If removing the belt eliminates the
are the result of normal operation. Some engines vibration, reinstall the belt and operate each
can have additional inherent vibration due to the accessory one at a time in order to see which has
cylinder arrangement, the design, and the the most effect on the vibration. However, one
firing order. component may affect another because the drive belt
The key to resolve an inherent engine disturbance is drives all of the accessories.
to isolate the vibration from the passenger Verify that the accessory load is not exciting the
compartment. Follow the same procedures as engine firing frequency.
described in Diagnosis and Repair of Engine Firing
Frequency-Related Vibrations.
Diagnosis
1. Remove the drive belts.
Engine Order Vibration Table 2. If the vibration stops, perform the following
steps:
Engine Order V6 60' and V6 90'
Single Cylinder Misfire or
2.1. Install the drive belts.
1/2 Order Torque Sensitive Bank-to-Bank EGR/Fuel Important: The drive belts drive all of
Variation the engine accessories. Therefore, one
1st Order Imbalance
component may affect another.
Abnormal
2.2. Operate each accessory one at a time in
Bank-to-Bank EGR/Fuel
1.5 Order Torque Sensitive order to see which has the most effect
Variation
on the vibration.
2nd Order Normal Inspect for accessory load affecting the engine
3.
2nd Order Torque Sensitive firing frequency.
3rd Order Torque Sensitive Normal 4. Inspect the pulleys for misalignment or bends.
Repair or replace as needed.
4th Order Torque Sensitive
5. Inspect the A/C system for an overcharge

condition. Evacuate and recharge the system
as needed.
7995 -
MD-lsuzu
Repair Instructions under the same conditions. Correcting the existing

tire and wheel assemblies is the most accurate and
General Service Precautions least time consuming approach. This is due to
vehicle-to-vehicle sensitivities and the differences
Caution: One or more of the following guidelines between the hubs of any two vehicles.
may apply when performing specific required
tests in the work stall: Balancing Tires and Wheels
1. When a test requires spinning the drive
Caution: Failure to adhere to the following
wheels with the vehicle jacked up: precautions before tire balancing can result In
On vehicles equipped with a limited-slip

personal injury or damage to components:
differential, do not attempt to spin one Clean away any dirt or deposits from the
1.
drive wheel with the other wheel on the inside of the wheels.
ground. The vehicle may drive through
this wheel and cause the vehicle to move 2. Remove any stones from the tread.
unexpectedly, or drive off the safety 3. Wear eye protection.
stands. This may result in personal injury 4. Use coated weights on aluminum wheels.
or damage.
Important: The tires can be balanced either
Do not exceed 56 km/h (35 mph) when

on-vehicle or off-vehicle, but the off-vehicle balancing
spinning one drive wheel with the other procedures are recommended. Off-vehicle methods
drive wheel stopped. This limit Is are better because tire rotation will not affect the
necessary because the speedometer balancing. The off-vehicle balancers are also more
indicates only one-half the actual wheel accurate than the on-vehicle balancers. Off-vehicle
speed under these conditions. If all drive balancers can perform dynamic balancing as well as
wheels are spinning at the same speed, static balancing.
do not exceed 112 km/h (70 mph).
Personal injury may result from excessive
speed wheel spinning. All persons should
stay clear of rotating components and
balance weight areas to avoid possible
personal injury.
When running an engine in the repair stall

for an extended period of time, use care

not to overheat the engine and
transmission.
2. When a test requires jacking up the vehicle
and running with the wheels and brake drum
removed:
Do not apply the brake with the brake

drums removed.
Do not place the transmission in Park

with the propeller shaft still spinning.

Turn off the ignition to stop the

powertrain components from spinning.
Correcting Tire and Wheel Vibration

A first order tire and wheel vibration is usually the
result of one of the following five conditions:

Excessive radial runout

Excessive lateral runout

Excessive imbalance

Excessive radial force variation
Excessive lateral force variation
These conditions must be eliminated one at a time 95621
in order to attain a set of tires that are free from
vibration causing elements. Substitute a set of tires Tire and wheel balancers can drift out of calibration
from another vehicle only as a last resort, and only without warning, or can become inaccurate as a
after the tires have been tested on a similar vehicle result of abuse. The balancer calibration should be
inspected every two weeks, and whenever the
readings are questionable.
1998 -
MD-lsuzu
Tire Balancer Calibration Test

1. Spin the balancer without a wheel or any of the
adapters on the shaft.
2. Inspect the balancer readings.
Specification
0.00-0.25 oz
3. Balance a tire and wheel assembly that is
within radial and lateral tolerances to ZERO.
4. Add a 3 ounce test weight to the wheel at any
location.
5. Spin the tire and wheel assembly again, noting

the readings.

modes, the
In the static and dynamic
balancer should call for 3 ounces of weight,
180 degrees opposite the test weight.
.In the dynamic mode only, the weight should
be called for on the flange of the wheel
opposite the last weight. 95624
6. With the assembly unbalanced to 3 ounces,

Dynamic balance, or two-plane balance, affects
cycle the balancer 5 times.
the distribution of weight on each side of the
7. Take the balancer readings: tire/wheel centerline.
Specification Most off-vehicle balancers are capable of checking
Variation: 0.25 oz or less both types of balance simultaneously.
8. Index the tire and wheel assembly at four As a general rule, most vehicles are more sensitive
separate locations on the balancer shaft, to static imbalance than to dynamic imbalance, with
90 degrees apart. as little as 0.50-0.75 oz capable of inducing a
9. Cycle the balancer with the assembly at each vibration in some vehicles. Vibration induced by
location. static imbalance will cause a vertical or BOUNCING
10. Take the balancer readings: motion of the tire.
Specification Dynamic imbalance results in a side-to-side motion
Variation: 0.25 oz or less of the tire. This motion is referred to as SHIMMY.

Balance all four tires as close to ZERO as
Tire Balancing Guidelines possible.
Static and dynamic balance are two kinds of Carefully follow the wheel balancer
tire/wheel balance:
manufacturer's instructions for proper mounting
techniques to be used on different types of
wheels.

Regard aftermarket wheels, especially those
incorporating universal lug patterns, as potential
sources of runout and mounting problems.

Use the correct coated weights on aluminum
wheels.

Recheck the tire and wheel assemblies for
excessive runout after they have been
corrected and installed.

Evaluate the vehicle at the complaint speed
and note if the vibration has been corrected.
If the vibration is still present, or is reduced but
still unacceptable, you may find one of two
possibilities:
-
On-vehicle imbalance
-
Radial or lateral force variation
95623
Static balance, also called single plane balance,

affects the distribution of weights around the
wheel circumference.
1998 -
MD-lsuzu
Correcting On-Vehicle Imbalance Follow the on-vehicle balancer manufacturer

On-vehicle imbalance may result from components operator's manual for specific instructions while
other than the tire and wheel assemblies having keeping the following tips in mind:
imbalance. An on-vehicle high-speed balance or Balancing Tips
replacement of suspected components may be

Do not remove the off-vehicle balancing
necessary in order to correct the condition.
weights. The purpose of on-vehicle balance is
Rotors do not have a set tolerance. However, rotors to FINE TUNE the assembly balance already
with more than 0.75 ounce imbalance have the
achieved, not to start over again.
potential to cause vibration. The rotors can be
If the on-vehicle balance calls for more than
inspected for imbalance using either the on-vehicle
1 ounce of additional weight, split the weight
or the off-vehicle method as described below:
between the inboard and outboard flanges of
Checking Rotor Imbalance (On-Vehicle) the wheel, so as not to upset the dynamic
balance of the assembly that was achieved in
1. Support the vehicle rear axle on a suitable
the off-vehicle balance.
hoist. Refer to Lifting and Jacking the Vehicle in
General Information.
An EVA vibration sensor placed on the fender
of the vehicle during the on-vehicle balance is
2. Remove the rear tire and wheel assemblies.
Refer to Wheel Removal (Dual/Rear) in Tires an excellent indicator of the amplitude of the
vibration, and the effect that the balance has
and Wheels.
on the vibration.
3. Reinstall the wheel nuts in order to retain
the rotors.

Evaluate the vibration after the on-vehicle
balance in order to determine if the vibration
4. Take the necessary precautions. Refer to Work condition has been resolved.
Stall Test Caution in Cautions and Notices.
Radial Force Variation
5. Run the vehicle at the complaint speed while
inspecting for vibration.
6. If the vibration still exists, perform the

following steps:
6.1. Remove the rotors.

6.2. Run the vehicle back to speed.
7. If the vibration is eliminated, perform the
following steps:
7.1. Remove the rotors one at a time.

7.2. Perform the vibration test for each rotor.
7.3. Replace the rotor causing the imbalance.
7.4. Inspect the balance of the new rotor.
Checking Rotor Imbalance (Off-Vehicle)
1. Measure the diameter and the width of the
rotor.
2. Mount the rotor on a balancer in the same
manner as a wheel.
Important: The rotors can only be inspected for 176971
static imbalance. Ignore the dynamic imbalance
Radial force variation is the difference in the stiffness
reading.
of tire as the tire rotates and contacts the road.
a
3. Inspect for static imbalance.
The tire and wheel assemblies have some variation
due to splices in the tire plies. These splices do not
On-Vehicle Balancing Procedure
cause a problem unless the force variation is
The vibration problem may not be correctable with
excessive. These STIFF SPOTS in the tire (1) can
the components removed from the vehicle. An deflect the tire and wheel assembly upward as the
on-vehicle high-speed balancer may be required in assembly contacts the road.
order to balance the tire and wheel assemblies while
If the tire has only one stiff spot, the spot will deflect
still mounted on the vehicle. On-vehicle balancing
will balance the hubs and the rotors simultaneously,
the spindle once per each revolution of the tire and
wheel assembly, thus causing a first-order tire/wheel
and will compensate for any residual runout
vibration. If the tire has two stiff spots, the spots
encountered as a result of mounting the tire and
wheel assemblies on the vehicle as opposed to cause a second-order vibration. First- and
off-vehicle balancing.
second-order tire/wheel vibrations are the most
common to occur as a result of radial force variation.
Third-, fourth-, or higher orders are possible but
rarely occur.
1998 -
MD-lsuzu
The most effective way to minimize the possibility of A lateral force variation condition is rare. The best
force variation as a factor in tire and wheel assembly way to eliminate lateral force variation as a factor in
vibrations is to ensure that the tire and wheel tire and wheel vibration conditions is to ensure that
assembly runout is at an absolute minimum. the lateral runout of the tire and wheel assemblies is
However, some tire and wheel assemblies exhibit at an absolute minimum.
vibration-causing force variation even though they The vehicle will "wobble" or "waddle" at slow speeds
are within runout and balance tolerances. These of 8-40 km/h (5-25 mph) when lateral force variation
instances are becoming rare due to tighter is excessive. This condition is usually related to the
tolerances and higher standards in manufacturing. first-order of tire and wheel rotation.
The following two alternatives are available if force
variation is suspected as a factor in tire and wheel Wheel Hub/Axle Flange Runout
assembly vibration complaints: Inspect the wheel hub/axle flange runout when
. Buff the tires. lateral runout occurs during on-vehicle testing but not
during off-vehicle testing. The tolerances provided
Substitute one or more known good tire and
are only guidelines. Perform corrections only if the
wheel assemblies.
on-vehicle runout cannot be brought to within
The tires may be buffed on a tire matching machine tolerance.
that is designed to remove small amounts of rubber
from the outer rows of the tread blocks at the
location of the stiff spots under load. This eliminates
the spindle deflection. This type of equipment is not
currently in widespread use. Do not use a TRUER or
any tool that is designed to make the tire perfectly
round. These tools will not correct the condition.
You may substitute one or more known good tire
and wheel assemblies when a tire manufacturer is
not available locally.
Lateral Force Variation
C3C3U
205276
1. Position the dial indicator on the machined

surface of the hub, the axle flange, or the rotor,
D D outside of the wheel studs.
2. Rotate the hub in order to find the low spot.

3. Set the dial indicator to zero at the low spot.
4. Rotate the hub again and check the total
amount of runout.
Specification (Guideline)
Runout tolerance: 0.130 mm (0.0050 in)
301905
Lateral force variation tends to deflect the vehicle

sideway, or laterally. Lateral force variation is based
on the same concept as radial force variation. A
SNAKY belt inside the tire may be the cause of
lateral force. The tire substitution method may have
to be used before tire replacement.
1998 -
MD-lsuzu
Wheel Stud (Stud Circle) Runout Locate the wheel weights on the inboard rim flange.
If during static balancing more than 28 grams
Use the following procedure whenever the off-vehicle
(1 ounce) is needed, split the weights as equally as
radial runout and the on-vehicle radial runout are
significantly different, and earlier attempts to correct possible between the inboard and outboard flanges.
the tire and wheel vibration condition have not been Special polyester-coated clip-on wheel weights are
successful. to be used to balance factory aluminum wheels.
These weights are designated MC or P, and must
be used on aluminum wheels having a wide,
7.6 mm (19/64 inch) flange. A plastic tipped hammer
should be used to prevent damage to the weight's
coating during installation.
Adhesive wheel weights are also available. Use the
following procedure to install adhesive wheel weights.
1. Determine where the wheel weight is to be
located on the inboard side of the wheel and
clean that area by sanding it to bare aluminum.
Do not sand the outboard side of the wheel as
this will damage the clear coat finish.
2. Wipe the sanded area with a mixture of half

ispopropyi alcohol and half water. Use a clean
cloth or paper towel.
3. Dry the area with hot air until the wheel surface
is warm to the touch.
4. Warm the adhesive backing on the wheel

balance weight to room temperature.
205279
5. Remove the tape from the back of the weight.
1. Position the dial indicator in order to contact the Do not touch the adhesive tape.
wheel mounting studs. 6. Apply the wheel weight and press on with hand
Measure the stud runout as close to the flange pressure.
as possible. 7. Secure the wheel weight with a 70 to 110 N.m
(16 to 25 Ib ft) force applied with a roller.
2. Turn the hub to register on each of the studs.
3. Zero the dial indicator on the lowest stud. Correcting Non-Uniform Tires
4. Rotate the hub again and check the total Use the following two methods to correct tires which
amount of runout.
cause a vibration, although the tires are balanced
Specification (Guideline) properly:
Runout tolerance: 0.80 mm (0.030 in) 1. This method uses an automatic machine that
loads the tire and buffs small amounts of
Wheel Weight Usage rubber from high spots on the outer two
tread rows.
Using this method in order to correct the
tires is usually permanent. This method does
not significantly affect the appearance or the
tire tread life.
Do not true the tires with a blade-type
machine. This reduces the tread life
substantially, and this often does not
permanently correct the problem.
2. The second method is to dismount the tire and
rotate it 180 degrees on the rim. It is important
that this is be done on the tire and wheel
assemblies which are known to be causing a
vibration, as it is just as likely to cause good
TYPEMC TYPEP
assemblies to vibrate.
218175
1998 -
MD-lsuzu
Correcting Driveline Vibration -
RWD and 4WD

Diagnosis will be much easier once you have identified
a vibration as first-order of driveline rotation during the
road test. Then identify the exact area that the
vibration is coming from and take proper action.
2
In most cases, vibration may be reproduced in the
stall. In the stall the vibration may be better or worse
Z. than that experienced during the road test.
The objective is to reduce the vibration to the lowest
point possible in the stall, than evaluate the results
on a road test. Many times, a vibration you were
4 3 able to reduce drastically in the stall will be
completely eliminated on the road.
The cause of first-order drive line vibration is usually
excessive runout or an imbalanced component.
The following procedure offers a systematic process
of elimination in order to determine which component
182256 is at fault:

vehicle on a hoist or heavy stands. Refer to
Information.
2. Remove the rear tire/wheel assemblies. Refer to
Wheel Removal (Dual/Rear) in Tires and Wheels.
3. Remove the brake drums. Refer to Brake Drum
Replacement in Air Drums.
4. Inspect the propeller shaft. The propeller shaft
should be free of undercoating before
continuing this diagnosis.
5. Inspect the propeller shaft or U-joints for any

obvious dents or damage. Dents or damage will
contribute to first-order driveline vibrations.

7. Place the transmission in gear.
8. Run the vehicle up to the speed at which the
vibration was most severe. Do not step on the
brake while the brake drums are removed.
9. Note the vibration present, and at what speed.
10. If the vibration is not present, refer to
First-Order Driving Vibration Testing (Torque
Sensitive) in the Road Testing Diagnosis.
11. If the vibration is present, determine which end
of the driveshaft is vibrating the most. Hold
your hand against the pinion nose and the
transmission tailshaft, or hold an EVA vibration
sensor up to each component.
12. If the vehicle is equipped with a two-piece
propeller shaft, inspect the center support
bearing for vibration.
13. If the transmission tail is vibrating, touch the
transmission crossmember under the
transmission mount. If there is no vibration on
the crossmember, then the transmission mount
is working properly.
14. Note which end of the driveshaft is the worst, and

how severe the vibration is. The inspection will be
a reference by which to judge future progress.
1998 -
MD-lsuzu
General Diagnosis and Correction 0-77
Information________________Vibration
Helpful Hints
Do not fill the propeller shaft with foam, oil, or any
other substance in order to correct a vibration. Filling
the propeller shaft is only effective in reducing an
unrelated condition called Torsional Rattle. Filling the
propeller shaft should only be done in strict
adherence to the procedure outlined in corporate
bulletins that address Torsional Rattle. Failure to
follow the correct procedure will induce a vibration
and/or affect the structural integrity of the propeller
shaft. The propeller shaft will then have to be
replaced.
Propeller Shaft Runout

A propeller shaft or pinion (companion) flange with
excessive runout causes first-order driveline
vibrations. Use the following procedure in order to
measure runout of the propeller shaft (2). The
tolerances are critical for smooth operation of the
driveline.
.
Remove excess corrosion of the propeller shaft
surface before checking runout. Also inspect for
damage and dents. Replace dented propeller
shafts. Remove any undercoating from the
propeller shaft before proceeding.
.
The measurement procedure that follows
applies to all one-piece and two-piece propeller
shaft assemblies.
The splined end (1) of a propeller shaft is
critical to the smooth operation of a two-piece
propeller shaft. When checking stub-shaft
runout, ensure that the dial indicator readings
are accurate.
Measuring Propeller Shaft Runout

Tools Required
J 8001 Dial Indicator
J 7872 Magnetic Base Dial Indicator Set
1. Raise the vehicle on a suitable hoist. Refer to
Information.
2. Allow the wheels to spin freely.
3. Attach J8001 and J 7872
1998 -
MD-lsuzu
4. Place the transmission in Neutral. Rotate the

pinion flange or transmission yoke by hand
while taking the measurements for runout. The
propeller shaft will turn easier in one direction
than in the other. Removing the wheels and
drums will also help.
5. For one piece propeller shafts, if the runout
exceeds the tolerances at one or more points:
5.1. Rotate the propeller shaft 180 degrees in
the pinion flange. Reinstall the propeller
shaft and recheck the measurement.
If the runout still exceeds the tolerance,
5.2.
double-check the pinion flange runout
before replacing the propeller shaft.
5.3. Do not include fluctuations on the dial
indicator due to welds or surface
irregularities.
6. For two-piece propeller shafts, if the runout

exceeds the tolerances at one or more points:
176029
6.1. Measure the rear propeller shaft.
6.2. Mark the position of the rear shaft in the
pinion flange, then remove the rear shaft.
6.3. Measure the front propeller shaft runout

on the tube and the stub shaft.
6.4. Replace the propeller shaft if either

measurement is out of tolerance.
Refer to Specifications in Vibration Diagnosis and
Correction.
Important: When you replace a propeller shaft,
check the new shaft for runout. Double-check the
pinion flange runout if the replacement shaft runout
is also out of tolerance.
Measuring Pinion Flange Runout

Tools Required
. J 23409 Dial Indicator Extension
J 35819 Pinion Flange Runout Gauge
1. Place the vehicle on a suitable hoist. Refer to

Information. Allow the wheels to rotate freely.
2. Remove the propeller shaft from the pinion
flange.
3. Install the J 35819 Pinion Flange
Runout Gauge
Important: The dial indicator will have inverted

readings. You are measuring the inside
diameter of the flange, and not the outside
diameter. The highest reading on the dial
indicator is the low spot. The lowest reading is
the high spot.
4. Rotate the pinion shaft 360 degrees and zero
the dial indicator on the low spot.
5. Rotate the pinion flange again and record the
total runout.
6. If the pinion flange runout is 0.15 mm (0.006 in)

or less, remove the pinion flange balance
weight.
1998 -
MD-lsuzu
General Information Vibration Diagnosis and Correctioh 0-79
7. If the pinion flange runout is over 0.15 mm

(0.006 in) but no less than 0.28 mm (0.011 in),
and the runout compensation weight is at or
near the low spot, then no further action is
necessary. Remove the weight if the runout
compensation weight is not at or near the
low spot.
8. If the pinion flange runout is more than

0.28 mm (0.011 in) but no greater than
0.38 mm (0.015 in), and the balance weight
is at or near the low point, then no further
action is necessary. Remove the weight and
re-index the pinion flange until the runout is
0.25 mm (0.010 in) or less if the runout
compensation weight is not at or near the
low spot.
9. Replace the pinion shaft when the runout is

0.25 mm (0.010 in) or less. Then, recheck the
runout. Service replacement flanges do not
have balance weights.
Helpful Hints
If necessary, add compensation weights on the
face of the pinion flange dust slinger. These
weights are tack-welded onto the slinger. You
may remove the weights with a die-grinder.

Carefully remove the spot weld at either end of
the weight.

Do not remove the weight unless you have
inspected the pinion flange runout and the
procedure calls for weight removal.
Do not remove any weights on the outboard
edge of the dust slinger. These weights are
present in order to internal axle components.
The weights are not related to the pinion
flange runout.
182274
Correcting Vibration at the Pinion Nose

Most first-order driveline vibrations originate at the
pinion nose end of the driveshaft. Ensure that the
vibrations are at a minimum at this location in order
to achieve acceptable results. Reduce the runout of
the components to a minimum. Balance the driveline
as a system when necessary.
1. Measure the runout of the propeller shaft and
check the tolerance.
2. If the tolerance is excessive, mark the position
of the shaft for future reference and rotate the
shaft 180 degrees.
3. Reinstall the shaft and recheck the runout.
Inspect the level of vibration in order to
determine if the vibration is lower or corrected.
182281
1998 -
MD-lsuzu
0-80 Vibration Diagnosis and Information
Correction_________________General
4. If the runout is still excessive, or if the vibration
is still present, refer to Measuring Pinion Flange
Runout. Replace the pinion flange or re-index
the flange 180 degrees if the pinion flange
runout exceeds the tolerance.
Remove and reinstall the pinion flange only
once on axles utilizing a "crush" type sleeve.
Replace the sleeve with a new sleeve if the
sleeve is "crushed". Removing the sleeve
requires removal of the ring and pinion set.
Therefore, replace flanges with excessive
runout. Regardless of the method used,
measure the pinion flange runout in order to
ensure that the flange is within tolerance.
5. Recheck the propeller shaft runout if the
vibration is present after the pinion flange
runout is corrected. If the propeller shaft runout
is still excessive, correct the runout before
doing a driveline system balance. Either replace
the shaft with a shaft that is within tolerance or
sublet the shaft to a reputable independent for
straightening and re-balance. Ensure that the
new or rebuilt shaft is within runout tolerance
before you continue.
6. Once the propeller shaft and pinion flange are

within runout tolerances, check if the vibration
is gone. If the level of the vibration is still
unacceptable, perform a driveline system
balance procedure.
Correcting Vibration at the Transmission

Tailshaft
First-order driveline vibrations that originate at the
transmission end of the propeller shaft are rare. If
the tailshaft of the transmission is vibrating, inspect
the tailshaft housing bushing for wear or damage.
A leaky transmission tailshaft oil seal indicates
bushing problems.
Feel for vibration at the crossmember underneath the

transmission mount. If there is no vibration, the
transmission mount is doing its job of isolating the
vibration from the structure of the vehicle. The
transmission mount is therefore probably not cause
of vibration.
Use the following procedure if you can feel vibration

on the crossmember and the tailshaft bushing, and if
transmission output is normal:
1. Measure the propeller shaft runout. If the runout

is excessive, replace the shaft with one that
has acceptable runout. Alternatively, sublet the
shaft to a reputable independent service shop
in order to have the shaft rebalanced and the
runout corrected.
2. Test drive the vehicle. If the vibration is still

unacceptable, balance the shaft on the vehicle.
Refer to Roughness or Vibration (Propeller
Shaft Runout) in Propeller Shaft.
1998 -
MD-ISUZU
Correcting Vibration at the Center Support

Bearing
These guidelines apply to the two-piece propeller or
three-piece shafts only. First-order driveline vibrations
that occur mainly at the center support bearing (2)
are usually the result of excessive runout at the stub
(splined) shaft (3).
Unlike other first-order driveline vibrations, these
vibrations can appear at unusually low speeds of
40 km/h (25 mph) and up.
Follow the following procedure to correct this type of
vibration:
1. Mark the position of the rear propeller shaft at
both ends for proper reassembly. Remove the
rear propeller shaft form the vehicle.
2. Measure the runout of the splines about
12.7 mm (0.5 in) from the end (1).
3. Replace the shaft if the runout exceeds the
tolerances. 182285
Stub shaft/spline runout 0.076 mm (0.003 in)
Troubleshooting Hints
Vibration is eliminated with the correction of the
propeller shaft runout. If some vibration is still
present, perform a vehicle road test. Then, determine
if an on-vehicle system balance is necessary.
Driveline System Balance with Electronic

Vibration Analyzer (EVA)
To pinpoint the source, you must reproduce the
vibration in the service stall and then determine
which component is vibrating the most using
the EVA:
1. Support the vehicle on a suitable hoist or on
safety stands. Ensure that the rear of the rear

axle is at curb height. Do not allow the axle to
hang. Refer to Lifting and Jacking the Vehicle
in General Information.
2. Remove the rear tire/wheel assemblies. Refer

to Wheel Removal (Dual/Rear) in Tires and
Wheels. 182137

4. Ensure that the propeller shaft is free of
undercoating. Check for dents or damage to the
propeller shaft or U-joints.
5. Start the engine. Place the transmission in gear

and run at the vehicle speed at which the
vibration occurs at.
Determine which end of the propeller shaft is
vibrating the most. Hold the EVA'S sensor against the
pinion nose and the transmission tailshaft assembly.
The higher the amplitude reading, the greater the
vibration.
If the vehicle has a two-piece propeller shaft, check
the center support bearing.
If the transmission tailshaft vibrates, check the
transmission crossmember under the transmission
mount. The vibration should not be present if the
mount is doing its job.
1998 -
MO-lsuzu
Runout and Balance Testing with the

Electronic Vibration Analyzer (EVA)
Ensure that the runout of the various driveline
components are within specifications. If the runouts
are within specifications, strobe balance the driveline.
The EVA is able to simplify the balancing process,
using the following procedure:
1. Use the EVA in order to determine which end

of the propeller shaft has the most vibration.
2. Mark the end of the propeller shaft (1) that has

the most vibration at four points, 90 degrees
apart. Number the marks 1 through 4 (2).
3. Mount the EVA sensor onto the bottom of the


The differential housing

The center bearing support (for two-piece or
three-piece propeller shafts)

The transmission tailshaft assembly
4. Position the sensor as close to the propeller
shaft as possible. Ensure that the UP side of
the sensor faces up. Ensure that the sensor is
horizontal.
6. Turn off all engine accessories.
o.o 1.0 2.0 7. Place the transmission in gear.
8. Run the vehicle at the speed which causes the
most vibration in the propeller shaft.
9. Hook the timing light clip to the trigger wire.
10. Plug the vibration sensor into Input A of the
182176 EVA. Input B does not have strobe light
capability.
11. Verify that the predominant frequency on the
EVA display matches the frequency of the
original vibration. Use the strobe light only if the
rotation speed of the propeller shaft is the
predominant frequency.
12. The EVA displays a series of questions in order
to select the correct filter. Press YES in order
to select the desired filter. Ensure that the
frequency is in the middle of the filter range.
Use the full range only as a last resort.
13. The display shows the test frequency, the
amplitude and the filter range. The driveline is
balanced when the amplitude is near two. In
some cases a slightly higher amplitude will
provide adequate balance.
14. Point the timing light at the propeller shaft. The
strobe effect will appear to freeze the propeller
shaft. Note which of the numbered marks is at
the bottom of the propeller shaft, or the 6
o'clock position. This position is the light spot.
15. Turn the engine off.
16. Install a weight directly on the light spot.
18. Run the vehicle at peak vibration speed.
19. Strobe the propeller shaft again.
The propeller shaft is balanced if the strobe image is
erratic and the amplitude is near two.
7998 -
MD-lsuzu
The propeller shaft is not balanced if one of the
following conditions exist:
The weight and the original light spot are at the
6 o'clock position.
The above condition means that there is not

enough weight on the propeller shaft. In order
to correct the balance, add a second weight
next to the first weight. Inspect the balance
again using the strobe light.
If the weights are now between 90 and
3 o'clock positions) too much weight exists.
In order to correct the balance, split the two
weights equally on either side of the original
light spot in order to produce a total weight
between one and two weights (between 0 and
120 degrees apart). Inspect the balance again
using the strobe light. Adjust the weights as
necessary.
The weight and original light spot are 90 to
3 o'clock positions).
The above condition means that one weight is

too much. In order to correct the balance, split
the two weights equally on either side of the
original light spot in order to produce a total
weight less than one (between 120 and
180 degrees apart). Inspect the balance again
using the strobe light. Adjust the weights as
necessary.

The weight and the original light spot are within
180 degrees of the 6 o'clock position.
Move weight towards the 6 o'clock position.
Inspect the balance again using the strobe light.
Adjust the weight as necessary. Refer to the
previous two conditions.
If the shaft will not balance using two weights, then
182137
place a third weight on the light spot. Split the first
two weights in order to produce a total weight
between two and three weights.
If three weights fail to balance the driveline, then
replace the propeller shaft.
When the propeller shaft balances, road test the
vehicle in order to verify that the vibration is
eliminated.
Driveline System Balance without the

Electronic Vibration Analyzer
The following procedure is designed to fine-tune the
balance of the propeller shaft while it is mounted in
the vehicle. The procedure also is able correct
residual imbalance of the remaining driveline
components.
Prior to balancing the driveline system, verify that the
propeller shaft and the pinion flange runout are
within specification.
1998 -
MD-lsuzu
Do not overheat the engine when performing this
procedure.
vehicle on a hoist or on safety stands. Do not
allow the axle to hang. Refer to Lifting and
Jacking the Vehicle in General Information.
2. Remove the rear tire/wheel assemblies. Refer

to Wheel Removal (Dual/Rear) in Tires and
Wheels.
4. Determine which end of the propeller shaft has
the most vibration in order to identify where to
begin installing the hose clamps.
5. Mark the end of the propeller shaft (1) which has

the most vibration at four points, 90 degrees
apart. Number the marks 1 through 4 (2).
The following procedure uses a trial and error
method of determining where to place the hose
clamps on the shaft. Use the following tips in order
to help locate the clamps:
1. Because the imbalance may be related to
propeller shaft runout, begin installing the
clamps at the low point of the propeller
shaft runout.
2. When the plant workers balance the propeller
shaft, they use weights in graduated
increments: 1/16 oz, 1/8 oz, etc. If the stock
weight is too light or too heavy, place the hose
0.0 1.0 2.0 clamp either directly in line with or opposite to
the stock weight.
The last method involves road testing the vehicle at
a speed which the vibration is felt.
1. Carefully hold a piece of chalk up to the very

end of the propeller shaft. Barely touch the
182176
chalk to the shaft.
2. Shut the engine off in order to stop the propeller
shaft from rotating. Do not step on the brake
pedal. Do not put the transmission in Park.
3. Inspect the chalk mark,
If you performed the above procedure correctly, the
chalk mark will indicate the heavy spot on the shaft.
The heavy spot deflected downward and touched the
chalk. If the chalk mark circle the entire shaft, touch
the chalk more gently to the shaft. Ensure that the
chalk touches only the heavy spot. Once the heavy
spot is located, place the hose clamp 180 degrees
opposite to the chalk mark. Then perform the
following steps:
1. Place the hose clamp at the light spot, or at

any of the four points marked previously.
2. Test drive the vehicle at the speed at which the
vibration occurred. Record any changes in the
vibration.
3. Move the clamp to the other positions.
4. Test drive the vehicle each time the clamp is
moved. Record any changes in vibration. Note
which position gives the best balance.
1998 -
MD-lsuzu
If the vibration does not change at all, or gets
worse,
then one clamp is too light or too heavy.
If the vibration did not change at all, then
repeat the procedure using two clamps
together.
If the vibration got worse, repeat the procedure
using two clamps separated. Separate the
clamps to reduce the spinning weight.
Continue the trial and error procedure using different
weights in different locations until you achieve the
best balance. If more that three clamps aligned in
the same position are required, then replace the
propeller shaft.
If you are able to reduce the vibration in the stall,
but are unable to eliminate the vibration completely,
perform a road test on the vehicle. A slight vibration
noticeable in the stall may not be noticeable on
the road.
Propeller Shaft Balance Weights 182176
When using clamps in order to

balance propeller
a
shaft with the total wight method, the correction

weight required will often be a fraction or a multiple
of one hose clamp. Use the following phasing
procedure with two hose clamp in order to accurately
place any required amount between zero weights
(0.0 total weight) to two weights (2.0 total weight).
Ensure that the clamps are located with even spaces
on either side of the light spot, or 180 degrees
opposite the heavy spot.
The following table contains the weight amounts in
terms of the total weight and the included angle
(spread) between the clamps.
The main objective of this section is to correct the

conditions that interfere with the proper cancellation
effect of the U-joints (1). The most common
condition, especially where the where launch
shudder is concerned, is incorrect driveline working
angles. However, other factors may aggravate the
condition.
Address these factors before you attempt to measure
or correct driveline working angles:

Worn, failed, damaged, or improperly installed vr=W^
U-joints (2).

Worn, collapsed, or improper powertrain mounts
.
Incorrect vehicle trim height adjustment for the
front suspension. This condition aggravates
launch shudder.

Incorrect trim height adjustment for the rear
suspension.
Trim height inspection includes trim heights that
are too low or too high. Vehicles equipped with 6498
aftermarket lift kits, vehicles that are constantly
loaded with cargo, and custom conversion vans
all fit in this category. On rear drive vehicles,
the pinion nose tilts upward as the rear trim
height is lowered.
If a second-order driveline vibration exists after these
conditions are corrected, measure and correct the
driveline angles.
1998 -
MD-lsuzu
If the complaint is present only with cargo in the
vehicle, perform the measurements with the vehicle
fully loaded. Once a second-order driveline vibration
has been corrected with the vehicle loaded, the
vibration may reappear with the vehicle unloaded.
The reverse of this is also true. You may have to
reach a compromise with the customer in this case.
Driveline Working Angles

Tools Required
J38460 Digital Inclinometer

J23498-A Driveshaft Inclinometer
J 23498-20 Driveshaft Inclinometer Adapter
Driveline working angle does not refer to the angle
of any one shaft, but to the angle that is formed by
the intersection of two shafts, as shown.
The procedure for measuring and correcting driveline
working angles depends on whether the vehicle is
equipped with a one or two-piece propeller shaft.
You need a J38460 Digital Inclinometer

The J 23498-A Driveshaft Inclinometer
The J38460 Digital Inclinometer

Use J 23498-20 Driveshaft Inclinometer Adapter
To verify the accuracy of the adapter, check the
angle of an angle of an accessible joint with
the inclinometer prior to assign it on an
inaccessible joint.
Preliminary Checks
Raise the vehicle on a suitable hoist or on safety
stands. Ensure that the rear axle is supported at
curb height and that the wheels are free to spin.
Refer to Lifting and Jacking the Vehicle in General
Information. Place the transmission in Neutral. Make
sure the vehicle has a full tank of fuel or the
equivalent amount of weight in the rear to simulate a
full tank. 3.8 liters of gasoline (one gallon) weighs
approximately 2.8 kg (6.2 Ib).
182316
1998 -
MD-lsuzu
Checking Phasing of U-joints
Inspect the propeller shaft for correct phasing. This
means that the front and rear U-joints are directly in
line or parallel with each other so that proper
cancellation takes place.
1. Rotate the propeller shaft so that the propeller

shaft rear U-joint bearing cap (1) is vertical
as shown.
2. Ensure that the front bearing cap (1) is also

vertical.
3. Place the inclinometer on the propeller shaft
rear U-joint bearing cap in order to ensure that
both U-joints are vertical.
4. Set the indicator line above the sight glass on

15 (the horizontal reference) and rotate the
propeller shaft until the bubble centers in the
sight glass. This brings the rear U-joint to
vertical.
5. Remove the inclinometer without disturbing the
setting. Leave the setting on 15 and install the
inclinometer on the front U-joint. The bubble
should remain centered plus or minus
3 degrees if the shaft is properly phased.
182325
The out of phasing of the single-piece propeller shaft

is very unusual. If the shaft is visibly out of place,
the end yokes are welded on in the wrong position,
or the shaft is damaged due to twisting. In either
case, replace the propeller shaft before continuing
with this procedure.
Measuring the Working Angles

The working angle of a U-joint is the difference
between the angles formed when two shafts
intersect. One piece propeller shaft systems have
two working angles, the front and the rear.
The two working angles should be equal within
1/2 of a degree.
The working angles themselves should not
exceed 4 degrees.
The working angles themselves should not be
equal to zero because a zero working angle will
cause premature U-joint wear due to lack of 301898
rotation of the U-joints.

The angle of the propeller shaft and the rear axle
pinion form the rear working angle (2). The angle of
the propeller shaft and the transmission output shaft
form the front working angle (1).
1998 -
MD-lsuzu
The angles of these components are most accurately

measured from the U-joint bearing caps. The bearing
caps should be free of corrosion or foreign material
to ensure accurate readings. Remove any snap rings
that may interfere wit the correct placement of the
inclinometer. Do not forget to reinstall them after you
take the measurements.
Take the measurements from the same side of the
propeller shaft to maintain consistent angle
measurements (either driver or passenger side).
It is extremely helpful to record the readings on a
diagram like the one shown as you proceed through
the measurements.
302013
Evaluation
The two working angles in a one-piece propeller
shaft system should be equal to within 1/2 of a
degree for effective cancellation.
Measuring Two-Piece Propeller Shaft System

Working Angles
Two-piece propeller shaft systems have three
working angles instead of two as in one-piece
systems.
The first angle (1) is the front working angle.
It is formed by the angle of the output shaft of
the transmission and the angle of the front
propeller shaft.
The second angle (2) is the middle working
angle. It is formed by the angle of the front
propeller shaft and the angle of the rear
propeller shaft.
301900
The third angle is the rear working angle. It is
formed by the angle of the rear propeller shaft
and the angle of the pinion yoke of the
rear axle.
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MD-lsuzu
This system has an odd joint that does not have
another joint to provide cancellation. Therefore, the
rear working angle and the middle working angle act
as a pair of joints to cancel each other out, like in
one-piece propeller shaft systems.
The front angle is considered the odd joint because
it does not have another joint to provide cancellation.
Because of this, the working angle of the odd joint
must be kept at or under 1/2 or a degree.
Keep the working angle of this odd joint to a
minimum so that there are not any great fluctuations
in speed that need to be canceled out. The front
joint is used as the odd joint because the front joint
angle does not change with suspension bounce,
rebound, or axle windup. For this reason, think of
the front propeller shaft of a two piece system as an
extension of the transmission output shaft.
302012
Measuring Three-Piece Propeller Shaft System

Working Angles
Three-piece propeller shaft systems have four
working angles instead of two as in one-piece
systems.
^
U* fl-
^dLg)
301902
The first angle is the front working angle. It is

formed by the angle of the output shaft of the
transmission and the angle of the front
propeller shaft.
The second angle is the middle working angle.
It is formed by the angle of the front propeller
shaft and the angle of the rear propeller shaft.
The third angle is the rear working angle. It is
formed by the angle of the rear propeller shaft
and the angle of the pinion yoke of the
An
rear axle.
This system has an odd joint that does not have
another joint to provide cancellation. Therefore, the
rear working angle and the middle working angle act
as a pair of joints to cancel each other out, like in
one-piece propeller shaft systems.
The front angle is considered the odd joint because
it does not have another joint to provide cancellation.
Because of this, the working angle of the odd joint 302009
must be kept at or under 1/2 or a degree.

1998 -
MD-lsuzu
Keep the working angle of this odd joint to a

minimum so that there are not any great fluctuations
in speed that need to be canceled out. The front
joint is used as the odd joint because the front joint
angle does not change with suspension bounce,
rebound, or axle windup. For this reason, think of
the front propeller shaft of a two piece system as an
extension of the transmission output shaft.
Propeller Shaft Phasing

The setup and measurement techniques are identical
to that of all propeller shaft systems. First, check for
proper phasing:
1. Turn the rear shaft so the rear U-joint is
straight up and down. Ensure that the front
(god U-joint of the (1) propeller shaft is also straight

up and down.
2. Rotate the shafts 90 degrees so that the front
propeller shaft front U-joint is straight up and
(t3=]Ml down. Ensure that the propeller shaft is also
straight up and down (actually part of the slip
2
yoke on the shaft) (1).
301817
If the two U-joints of the propeller shaft are not in

this phase (2), the two halves of the propeller shaft
may have been assembled incorrectly.
Propeller Shaft(s) Lateral Alignment

The procedure for lateral alignment of a propeller
shaft(s) is used for launch shudder or any
second-order, driveline vibrations. Adjust the lateral
alignment before you measure and adjust the
driveline angles.
1. Raise and suitably support the vehicle on a
hoist. Refer to Lifting and Jacking the Vehicle in
2. Look down the front of the propeller shaft.
3. If the propeller shaft is not straight, or if the
center bearing support, if equipped, is off to
one side, relocate center support bearing, if
equipped, to make the propeller shaft assembly
as straight as possible. Ensure that you do not
182343 create a ground-out condition against the
exhaust or another component.
1998 -
MD-lsuzu
If launch shudder or second-order driveline vibration
is still present,
measure and correct the driveline
angles.
Measuring Propeller Shaft Working Angles

This procedure is essentially the same, for all
propeller shaft(s). You must, however, take into
account the third angle if you have more than one
propeller shaft.
1. Place the inclinometer on the propeller shaft
bearing cap (1).
6499
2. Center the bubble in the sight glass and record

the measurement. The bearing cap must be
straight up and down to obtain accurate
measurement. Enter the measurements on
your diagram.
3. Rotate the propeller shaft 90 degrees and place
the inclinometer on the transmission output
yoke bearing cap. Again, the bearing cap must
be straight up and down to obtain an accurate
measurement.
4. Center the bubble in the sight glass and record
the measurement.
5. Subtract the smaller reading from the larger
reading to obtain the front U-joint working
angle.
6502
1998 -
MD-ISUZU
Evaluation
The working angle is within tolerance, following the
rule that the working angle of an odd joint in a
two-piece joint system is 1/2 degree or less. Notice
that in each of the good examples that the front
working angle (FWA) is 1/2 degree or less and is
treated as a separate joint. The middle working
angle (MWA) and rear working angle (RWA) are
subtracted and the difference (DIFF) is 1/2 degree
or less. The middle and rear joints may cancel
each other.
Correcting Working Angles

In order to change the working angles, shim the
components up or down. Look closely at the existing
angles. Use the existing angles and the shims in
order to achieve the correct working angles.
Compared to horizontal or true level, the components
182361 located at the rear of the vehicle are usually lower
than the components located at the front of the
vehicle. This condition is called "down in the rear".
If a component with a down in the rear angle is
shimmed up at the rear, then the shim will bring the
component closer to the horizontal (zero). Alternately,
if a component with a down in the rear angle is
shimmed down, then the component will move
farther from the horizontal (zero).
Rear Axle Wind-Up

Rear axle wind-up may cause launch shudder even
when all of the working angles are within
specifications. Rear axle wind-up occurs when heavy
torque during acceleration causes the pinion nose to
point upward. In order to compensate for axle
wind-up, tip the pinion nose downward. Install the
axle shims incrementally, performing a road test after
each shim. Add shims until the road test indicates
that the shudder is eliminated.
Rear Axle Shims

Wedge shims of different sizes are available through
GMSPO and independent suppliers for the purpose
of shimming the rear axle angle. GM shims are
available in two, three and four degrees.
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MD-lsuzu
Caution: Never attempt to shim a rear axle using

anything except shims that are designed for this
purpose. Failure to do so will result in the shims
falling out and a loss of vehicle control and that
could cause personal Injury.
Install the shims (5) in order to increase or decrease
the angle of the rear axle pinion. Install the shims
between the leaf spring (3) and the spring seat.
Depending on the design of the suspension (leaf
spring on top or underneath the axle), and the
direction of the desired change, install the shims with
either the thick side toward the front of the vehicle or
toward the rear of the vehicle.
Important: After installing the shims, ensure that the
U-bolt has two or three threads above the nut.
Ensure also that the center bolt, located in the
spring seat, is long enough to seat in the locator
hole. If these two conditions do not exist, use longer
U-bolts and center bolts. Longer U-bolts and center
bolts are available through local spring shops. 182364
Transmission Shims
If transmission requires shims, order the shims.
a
Installing most shims will change the transmission

angle approximately V2 degree.
When shimming transmissions, use a shim made
from steel stock at the necessary thickness. Ensure
that the shim contacts the full width of the area to
be shimmed. Do not use washers.
1998 -
MD-ISUZU
A vibrating component operates at a consistent rate
Description and Operation
(km/h, mph, or rpm). Measure the rate of vibration in
General Description question. When the rate/speed is determined, relate
the vibration to a component that operates at an
Vibration Theory equal rate/speed in order to pinpoint the source.
Vibrations also tend to transmit through the body
The vehicle designs and the engineering
structure to other components. Therefore, just
requirements have undergone drastic changes in this
because the seat vibrates doesn't mean the source
decade. The following factors drive many of these
of vibration is in the seat.
requirements:
Vibrations consist of the following three elements:

Increased fuel costs

Decreased fuel supplies
.
The source
the cause of the vibration
The transfer path the path the vibration
Corporate Average Fuel Economy (CAFE)

travels through the vehicle

Clean air legislation
The responder
the component where the
Foreign competition
vibration is felt

Crashworthiness
Rising customer expectations
The vehicle designs have evolved from the full frame
construction, where multiple isolating body mounts
were used, to the lighter unibody designs of today.
The unibody designs transfer any noise or vibration
faster.
The use of heavier V8 engines has been reduced,
being replaced with lighter, more fuel-efficient four
and six-cylinder engines. During this same period,
options such as A/C and PS have become more
popular. These types of options increase the engine
load, resulting in more unwanted noise and vibration.
The presence/absence of unwanted noise and
vibration is linked to the customer's perception of the
overall vehicle quality.
Vibration is the repetitive motion of an object, back
and forth, or up and down. The following conditions
cause most vehicle vibrations: 95585
A rotating component In the preceding picture, the source is the
The engine combustion process firing impulses unbalanced tire. The transfer path is the route the
Rotating components will vibrate with excessive vibrations travels through the vehicle's suspension
imbalance or runout. During vibration diagnosis, the system into the steering column. The responder is
amount of allowable imbalance or runout should be the steering wheel, which the customer reports as
considered a TOLERANCE and not a vibrating. Eliminating any one of these three
SPECIFICATION. In other words, the less imbalance elements will usually correct the condition. Decide,
or runout the better. from the gathered information, which element makes
the most sense to repair. Adding a brace to the
A vibration concern will occur when the firing
steering column may keep the steering wheel from
impulses of the engine are not properly isolated from
vibrating, but adding a brace is not a practical
the passenger compartment.
solution. The most direct and effective repair would
be to properly balance the tire.
1998 -
MD-lsuzu
For example, performing the following steps will help
demonstrate the vibration theory:
95586
Vibration can also produce noise. As an example,

consider a vehicle that has an exhaust pipe 95587
GROUNDED to the frame. The source of the a yardstick to the edge of a table,
1. Clamp
vibration is the engine firing impulses traveling leaving about 50 cm (20 in) hanging over the
through the exhaust. The transfer path is a grounded
edge of the table.
or bound-up exhaust hanger. The responder is the
frame. The floor panel vibrates, acting as a large 2. Pull down on the edge of the stick and release
while observing the movement of the stick.
speaker, which produces noise. The best repair
would be to eliminate the transfer path. Aligning the The motion of the stick occurs in repetitive cycles.
exhaust system and correcting the grounded The cycle begins at midpoint, continues through the
condition at the frame would eliminate the lowest extreme of travel, then back past the
transfer path. midpoint, through the upper extreme of travel, and
back to the midpoint where the cycle begins again.
Basic Vibration Terminology The cycle occurs over and over again at the same
The following are the two primary components of rate, or frequency. In this case, about 10 cycles in
vibration diagnosis: one minute. If we measure the frequency to reflect
The physical properties of objects the number of complete cycles that the yardstick
The object's properties of conducting made in one minute, the measure would be
10 cycles x 60 seconds = 600 cycles per
mechanical energy
minute (cpm).
The repetitive up and down or back and forth
We have also found a specific amount of motion, or
movement of a component cause most customer
vibration complaints. The following are the common amplitude, in the total travel of the yardstick from the
components that vibrate: very top to the very bottom. Redo the experiment as
follows:

The steering wheel
1. Reclamp the yardstick to the edge of a table,

The seat cushion leaving about 25 cm (10 in) hanging over the
. The frame edge of the table.
.
The 1/P 2. Pull down on the edge of the stick and release
Vibration diagnosis involves the following simple while observing the movement of the stick.
stepwise outline: The stick vibrates at a much faster frequency:
1. Measure the repetitive motion and assign a
30 cycles per second (1800 cycles per minute).
value to the measurement in cycles per second
or cycles per minute.
2. Relate the frequency back on terms of the
rotational speed of a component that is
operating at the same rate or speed.
3. Inspect and test the components for conditions
that cause vibration.
1998 -
MD-lsuzu
Cycle
95588
Legend
(1) 1st Cycle
(2) 2nd Cycle
(3) 3rd Cycle
(4) Time
Vibration Cycles in Powertrain Components The word CYCLE comes from the same root as the
word CIRCLE. A circle begins and ends at the same
point, as thus, so does a cycle. All vibrations consist
of repetitive cycles.
95589
Legend
(1) Spindle
(2) Pinion Nose
1998 -
MD-lsuzu
Legend
(1) Amplitude
(2) Reference
(3) Time in Seconds
(4) 1 Second
Frequency is defined as the rate at which an event Amplitude
occurs during a given period of time. With a
vibration, the event is a cycle, and the period of time
is one second. Thus, frequency is expressed in
cycles per second.
The proper term for cycles per seconds is Hertz
(Hz). This is the most common way to measure
frequency. Multiply the Hertz by 60 to get the cycles
or revolutions per minute (RPM).
Legend
(1) Maximum
(2) Minimum
(3) Zero-to-Peak Amplitude
(4) Peak-to-Peak Amplitude
1998 -
MD-lsuzu
Amplitude is the maximum value of a periodically Free Vibration

varying quantity. Used in vibration diagnostics, we
Free vibration is the continued vibration in the
are referring it to the magnitude of the disturbance. absence of any outside force. In the yardstick
A severe disturbance would have a high amplitude;
example, the yardstick continued to vibrate even
a
minor disturbance would have a low amplitude. after the end was released.
Amplitude is measured by the amount of actual
Forced Vibration
movement, or the displacement. For example,
Forced vibration is when an object is vibrating
consider the vibration caused by an out-of-balance
continuously as a result of an outside force.
wheel at 80 km/h (50 mph) as opposed to 40 km/h
(25 mph). As the speed increases, the amplitude
increases.
Centrifugal Force Due to an Imbalance
90 180 270 360 90
95594
Legend
(1) Location of Imbalance (Degrees)
(2) Centrifugal Force Acting on Spindle
A spinning object with an imbalance generates a is the imbalance in the tire. The string is the tire,
centrifugal force. Performing the following steps will wheel, and suspension assembly. As the vehicle
help to demonstrate centrifugal force: speed increases, the disturbing force of the
1. Tie a nut to a string. unbalanced tire can be felt in the steering wheel, the
seat, and the floor. This disturbance will be repetitive
2. Hold the string. The nut hangs vertically due to (Hz) and the amplitude will increase. At higher
gravity.
speeds, both the frequency and the amplitude will
3. Spin the string. The nut will spin in
circle. a increase. As the tire revolves, the imbalance, or the
Centrifugal force is trying to make the nut fly centrifugal force, will alternately lift the tire up and
outward, causing the pull you feel on your hand. An force the tire downward, along with the spindle, once
unbalanced tire follows the same example. The nut for each revolution of the tire.
1998 -
MD-lsuzu
Natural or Resonant Frequency Resonance
95595 95596
The natural frequency is the frequency at which an Legend

object tends to vibrate. Bells, guitar strings, and (1) Frequency cps
-
tuning forks are all examples of objects that tend to

(2) Suspension Frequency
vibrate at specific frequencies when excited by an
external force. (3) Unbalanced Excitation
Suspension systems, and even engines within their (4) Point of Resonance
mounts, have a tendency to vibrate at certain (5) Problem Speed
frequencies. This is why some vibration complaints
occur only at specific vehicle speeds or engine rpm. All objects have natural frequencies. The natural
The stiffness and the natural frequency of a material frequency of a typical automotive front suspension is
in the 10-15HZ range. This natural frequency is the
have a relationship. Generally, the stiffer the material,
the higher the natural frequency. The opposite is result of the suspension design. The suspension's
also true. The softer a material, the lower its natural natural frequency is the same at all vehicle speeds.
frequency. Conversely, the greater the mass, the As the tire speed increases along with the vehicle
higher the natural frequency. speed, the disturbance created by the tire increases
in frequency. Eventually, the frequency of the
unbalanced tire will intersect with the natural
frequency of the suspension. This causes the
suspension to vibrate. The intersecting point is called
the resonance.
The amplitude off a vibration will be greatest at the
point of resonance. While the vibration may be felt
above and below the problem speed, the vibration
may be felt the most a the point of resonance.
1998 -
MD-lsuzu
Damping
95597
Legend
(1) Low Damping
(2) High Damping
Damping is the ability of an object or material to
dissipate or absorb vibration. The automotive shock
absorber is a good example. The function of the
shock absorber is to absorb or dampen the
oscillations of the suspension system.
1998 -
MD-lsuzu
my ^niaaiiiy^
1+2=3
^\/ww\^^/w\| 10 Hz
2 :<
w
11111
/\v//\\y \y/\\y/\ /\i/\
/"X.
\y \y w /^: 8 Hz
3
.AV 11111
/\ /VA/V
V A,,^Â
VV^1
v
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95599
Two separate disturbances that are relatively close Order

together in frequency will lead to a condition called
Order refers to how many times an event occurs
beating, or phasing. A beating vibration condition will during one revolution of a rotating component.
increase in intensity or amplitude in a repetitive
fashion as the vehicle travels at a steady speed.
This beating vibration can produce the familiar
droning noise heard in some vehicles.
Beating occurs when two vibrating forces are adding
to each other's amplitude. However, two vibrating
forces can also subtract from each other's amplitude.
The adding and subtracting of amplitudes in similar
frequencies is called beating. In many cases,
eliminating either one of the disturbances can correct
the condition.
95600
For example, a tire with one high spot would create

a disturbance once for every revolution of the tire.
This is called first-order vibration.
1998 -
MD-lsuzu
EVA Basic Hookup

1. Inspect that the software cartridge is correctly
inserted at the bottom of the unit. (The
cartridge usually remains there at all times.)
2. Connect the vibration sensor cord into either

input A or B.
3. Line up the connector so that the release

button is at the bottom.
Important: Do not twist the connector. The

sensor should remain plugged into the unit at
all times.
4. Push the connector into the input until the

connector clicks and locks in place.
5. Plug the power cord into a 12-volt power feed
in order to turn the EVA
on. (There is no
ON-OFF switch.)
To Disconnect the sensor, press the release button
95601
and gently pull the connector straight out.
An oval-shaped tire with two high spots would create
a disturbance twice for every revolution. This is EVA Sensor Placement
called second-order vibration. Three high spots would
be third-order, and so forth. Two first-order vibrations
may add or subtract from the overall amplitude of
the disturbance, but that is all. Two first-order
vibrations do not equal a second-order. Due to
centrifugal force, an unbalanced component will
always create at least a first-order vibration.
Electronic Vibration Analyzer (EVA)
J 38792
95603
Proper EVA sensor placement is critical in order to

take proper vibration readings. The sensor can be
placed anywhere on the vehicle where vibrations are
felt. Use putty or a hook and loop fastener in order
to hold the sensor in place on non-ferrous surfaces,
such as the surface of the steering column.
95602
The J 38792 Electronic Vibration Analyzer (EVA) is

specifically designed to diagnose vibrations. This
hand-held device is similar to a scan tool. A
standard 12-volt power feed supplies the power. The
vibration sensor, or the accelerometer, is at the end
of a 6 m (20 ft) cord. The vibration sensor can be
mounted virtually anywhere on the vehicle where a
vibration is felt.
1998 -
MD-lsuzu
Freeze
Pressing the FREEZE button on the keypad
activates the freeze function, which locks the display
of data. The display shows FRZ at the top. The
freeze function is useful when conducting an
acceleration/deceleration test in which the significant
amount of vibration registers only for a very short
time. Pressing EXIT or the FREEZE button again
deactivates the freeze function.
Record/Playback
The displayed vibration information can be recorded
for later playback. The EVA retains stored data for
about 70 hours after the unit has been unplugged
from a power source. Data is recorded as
SNAPSHOTS of vibration information. Each snapshot
consists of 10 different frames. Up to 10 of these
snapshots can be recorded.
95604 Press RECORD in order to record a snapshot. The
A magnet is supplied in order to hold the sensor to screen will display R? in order to request a tag
number between 0 and 9. These tag numbers are
ferrous surfaces.
the individual frames of the snapshot recording. New
Vibrations are typically felt in an up-and-down data will replace the existing data when a number is
direction. The sensor is directionally sensitive. chosen that has already been used in order to tag a
Therefore, place the sensor as flat as possible with snapshot.
the side marked UP facing upward. Place the UP
Pressing PLAYBACK plays back the recorded data.
side of the sensor in the exact position every time
The screen shows P? in order to request the tag
for consistent results when repeating the tests or
making a comparison. number for the wanted snapshot. Once the number
is entered, the snapshot data is displayed: P and the
EVA Display tag number will appear. Then, an F and a 0-9 will be
displayed in order to indicate which frame of the
snapshot is being displayed.
The freeze function can be used in order to freeze
the display at any point in the sequence during
playback. Individual frames can be viewed in a
forward or backward sequence using the up and
down arrow keys.
The display returns to the active screen when the
recording or playback of a snapshot is finished, or
when EXIT is pressed.
HHEBIBB
BDDDB Averaging/Non-Averaging Modes
The EVA normally operates in an averaging mode
BDDDEi that averages multiple vibration samples over a

period of time. The averaging mode minimizes the
HDBBB effects of sudden vibration that are not related to the

problem (such as form potholes or uneven road
surfaces). Most tests use the averaging mode.
The EVA is more sensitive to vibrations in the
95605
non-averaging mode. The display is more
The EVA offers the following main display features, instantaneous and not averaged over a period of
all of which are described below: time. The non-averaging mode is used when

Freeze measuring a vibration that exists for only a short
period of time, and during acceleration/deceleration
Record/Playback
tests.
Averaging/Non-averaging modes
Pressing the AVG button switches between the
Strobe Balancing
averaging and non-averaging modes. The screen will

display AVG.
1998
MD-lsuzu
Strobe Balancing EVA Calibration
The EVA features the following two built in
J38792 calibration procedures:

Sensor Calibration

Phase Shift Calibration
A replaced or added sensor must be calibrated in
order to function properly with the EVA unit. The
phase shift calibration is performed at the factory
and should not be repeated under normal use.
Sensor Calibration
1. Lay the sensor on a flat stationary surface with
the UP side facing upward.
2. Plug the sensor into either input A or B.
3. Plug the EVA into a 12-volt power supply.
4. After the display initializes, select the
proper input.
5. Press the up arrow key.
6. Press the number 2 three times on the keypad.
The message BURNING will appear, followed
95606
by a request to turn the sensor over.
7. Turn the sensor over.
The EVA can strobe balance a rotating component.
A trigger wire is located on the top of the EVA, 8. Press any key in order to commence
calibration:
which is used in conjunction with an inductive
pick-up light strobe. The EVA triggers the strobe light
Calibration will take about 20 seconds.
at the same frequency as the vibration. The timing The display will return to the active mode
light clips on to the trigger wire. The vibration sensor when calibration is complete.
must be attached to input A. Input B does not Phase Shift Calibration
provide the strobe function. 1. Plug the EVA into a 12-volt power supply.
Pressing STROBE starts the strobe balancing 2. Press the down arrow key on the EVA keypad.
function. The EVA will ask a series of questions in 3. Press the number 2 three times in order to
order to determine the correct filter range: full, low, begin calibration:
or high. Do not press any key until the message ANY
The low and high ranges prevent other vibrations KEY TO CONTINUE appears. Pressing a key
will cancel the calibration process.
from interfering with the operation of the strobe light.
Use the full range as a last resort only. Press YES
The display will flash numbers for
in order to select a range. Press NO in order to go 5-6 minutes. (If the numbers flash for more
on to the next range. The vibration/strobe frequency than 10 minutes, the EVA is defective.)
must fall within the selected range. . The message BURNING PHASE SHIFT
CONSTANTS will appear for one minute.
The EVA will display the strobe frequency, amplitude,
and filter range. The EVA is now ready to begin the
. The BURNING CENTER FREQUENCIES
strobe balance procedure. LOW=39 HIGH=48 message will appear.
. The ANY KEY TO CONTINUE message
should appear.
4. Press any key in order to return to the
active mode.
1998 -
MD-lsuzu
Special Tools and Equipment

Illustration Tool Number/ Description Illustration Tool Number/ Description
J 34481
J8001
UniversI Flexable Magnetic
Dial Indicator Set
Dial Indicator Stand
2014 210346
J 23409 J 35819
Dial Indicator Extension Flange Runout Gauge
1517 1512
J 23498-A J 38460
Driveshaft Inclinometer Digital Inclinometer
8224 198883
J 23498-20 J 38792
Driveshaft Inclinometer Electronic Vibration
Adapter Analyzer (EVA)
180348 6826
199S -
MD-lsuzu
Illustration Tool Number/ Description
J7872
Magnetic Base Dial
Indicator Set
35463
1998 -
MD-ISUZU
Section 1
HVAC
Heating and Ventilation (Non-A/C)..............i-3 HVAC Systems with A/C -

Manual ...........1-57
Specifications......................................................1-3 Specifications....................................................1-57
Fastener Tightening Specifications..................1-3 Fastener Tightening Specifications................1-57
Schematic and Routing Diagrams ...................1-3 Compressor Specifications.............................1-57
Heater Blower Controls Schematic System
Capacities..........................................1-57
References ...................................................1-3 Refrigerant Oil Distribution Specifications.....1-58
Heater Blower Controls Schematics................1-4 Schematic and Routing Diagrams................. 1 -58
Component Locator............................................1-6 HVAC Schematic References........................1-58
Heater Blower Controls Components..............1-6 HVAC Schematic
Icons..................................1-58
Heater Blower Controls Component Views.....1-7 HVAC Blower Control Schematics.................1-59
Heater Blower Controls Connector HVAC Compressor Control Schematics........ 1-62
End
Views..................................................1-12 Component Locator..........................................1-65
Diagnostic Information and Procedures.......1-14 HVAC Components
........................................1-65
Blower Motor Inoperative at Any Speed.......1-14 HVAC Component
Views...............................1-66
Blower Motor Inoperative at High HVAC Connector End Views
Speed Only .........................1-75
................................................1-15 Diagnostic Information and Procedures....... 1-78
Blower Motor Inoperative at
Functional
Medium Speed...........................................1-16 Check............................................1-78
HVAC Blower Controls System Check..........1-78
Blower Motor Inoperative at
HVAC Compressor Clutch Does
Low Speed Only
........................................1-17 Not
Heating Insufficient.........................................1-17 Engage................................................1-79
HVAC Compressor Clutch Does
Heat Excessive...............................................1-18
Not Disengage
Repair Instructions...........................................1-19 ...........................................1-82
Blower Motor Inoperative at Any Speed.......1-82
Control Assembly Replacement.....................1-19
Blower Motor Low Speed Inoperative...........1-83
Blower Switch Replacement..........................1-20
Blower Motor Medium Speed Inoperative.....1-84
Blower Motor Resistor Replacement.............1-21
Blower Motor Low and Medium
Blower Motor and Fan Replacement ............1-24 Speeds Inoperative....................................1-85
Air Distributor Duct Replacement (Lower) ....1-27
Blower Motor High Speed Inoperative..........1-85
Air Distributor Duct Replacement (Upper) ....1-28
Condenser Fan Inoperative ...........................1-86
Air Inlet Actuator Replacement......................1-28
Condenser Fan On at All Times...................1-87
Temperature Actuator Replacement..............1-33 System Performance Chart ...........................1-88
Mode Actuator Replacement.........................1-37 Refrigerant System
Checks...........................1-89
Heater Pipes Replacement (Inlet).................1-41 Leak Testing
...................................................1-90
Heater Pipes Replacement (Outlet) ..............1-43 Heating
Insufficient.........................................1-92
Heater Core Replacement (Right).................1-45 Heat Excessive...............................................1-93
Heater Core Replacement (Left) ...................1-47 Cooling Insufficient A/C Inoperative............1-93
-
Heater/Vent Module Replacement.................1-50 Air Delivery

Improper.....................................1-94
Description and Operation..............................1-52 Repair Instructions...........................................1-94
Heater System Description............................1-52 Odor Correction..............................................1-94
Air Distribution System Description Refrigerant Recovery and Recharging..........1-95
...............1-53
Heater Blower Controls Circuit Description .....1-53 Compressor Replacement..............................1-96
Modes Description..........................................1-54 Compressor Sealing Washers
Replacement ..............................................1-99
1998 -
MD-lsuzu
Table of Contents HVAC
0-Ring Replacement............................ 1-101 Temperature Actuator Replacement........... 1-158

Compressor Magnetic Clutch Air Distributor Duct Replacement
.1-101 1-162
(Disassembly).................................., (Lower).....................................................
Compressor Magnetic Clutch Air Distributor Duct Replacement
1-102 1-163
(Assembly)........................................ (Upper).....................................................
Compressor Magnetic Clutch (Pulley), 1-103 Description and Operation........................... 1-164
Compressor Magnetic Clutch Operating 1-164
Modes.........................................
(Field ,1-104 Air Distribution System Description 1-165
Coil)........................................ ............
Compressor Magnetic Clutch Refrigeration System Description
(A/C Compressor ,1-105 (With 1-165
Seal)................... A/C)................................................
Compressor Overhaul.......................... ,1-108 Refrigeration System Description
Compressor Hose Assembly (Without 1-167
A/C)...........................................
Replacement.................................... ,1-108 Heater System Description ......................... 1-168
Evaporator Hose Assembly Refrigerant 1-168
R-134a......................................
Replacement.................................... ,.1-111 Handling Refrigerant 1-169
R-134a......................
Receiver Dehydrator and Evaporator Handling of Refrigerant Lines
Hose Assembly................................
,.1-115 and Fittings.............................................. 1-169
Receiver Dehydrator Replacement..... ..1-117 Maintaining Chemical 1-170
Stability....................
Thermal Expansion Valve Replacement......1-119 Evaporator Description................................ 1-170
A/C Temperature Sensor Replacement...... 1-122
Condenser Description................................ 1-171
Condenser Fan Replacement..................... 1-124 Accumulator Description.............................. 1-171
Condenser Replacement............................. 1-124 Compressor Description.............................. 1-171
Blower Motor Resistor Replacement.......... 1-128 Control Assembly Description..................... 1-171
Blower Motor and Fan Replacement.......... 1-131 Ventilation Description................................. 1-172
HVAC Module Assembly Replacement....... 1-134 1-172
Relays and Sensors Description ................
Evaporator Core Replacement.................... 1-135 ACR4 Procedures........................................ 1-173
Heater Core Replacement (Right).............. 1-139 HVAC Blower Controls Circuit
Heater Core Replacement (Left)................. 1-141 1-173
Description...............................................
Heater Pipes Replacement (Inlet)............... 1-143 HVAC Compressor Controls Circuit
Heater Pipes Replacement (Outlet)............ 1-144 Description............................................... 1-174
Passenger Compartment Air Filter HVAC Air Delivery Circuit Description........ 1-174
Replacement............................................ 1-145 HVAC Compressor/Condenser Fan
Description................................... 1-175
Control Assembly Replacement.................. 1-146 Circuit
Blower Switch Replacement........................ 1-147 Special Tools and Equipment...................... 1-176
Mode Actuator Replacement....................... 1-149 Special 1-176
Tools...............................................
Air Inlet Actuator Replacement................... 1-153
1998 -
MD-lsuzu
HVAC Heating and Ventilation (Non-A/C) 1-3
Heating and Ventilation (Non-A/C)

Specifications
Fastener Tightening Specifications

Specification
Quick Connect Heater Inlet Connector 35N.m 26lbft
Schematic and Routing Diagrams
Heater Blower Controls Schematic References

Reference on Schematic Section Number
Subsection Name
Fuse Block Details Cell 11 8Wiring Systems
Ground Distribution Cell 14 8Wiring Systems
Interior Lamps Dimming Cell 117 8Lighting Systems
1998 -
MD-lsuzu
Heater Blower Controls Schematics (Cell 60: HVAC Temperature Actuator)
-
HVAC ^.^
Recirculate/
f^ ^
i^nanaei
^f ^ I Switch | Fresh Actuator
1.25 GRN 216
E11, ,C212
E'
2 LT GRN 236
H G D
4'
0.8 PNK/ 232
5- 1'
0.8
3'
PNK 230
6-
I
BLK
0.8 PPU 235
WHT 0.8
2LTGRN 0.8 PPL/ 234 PNK/ 231
0.8
GRN 0.8LTGRN 229 LT GRN/
Ow9 0.5 PPL/ 233 BLU
'
197 WHT
YEL
2 LT GRN 197 B10 C71? B12|
r B11^
'
B9
D11, B6, C9, C8, ,C212 0.5
0.5 GRN 177 0.5 PNK/ 195 PNK 187
1.25LTBRN 171 0.5 PPL/ 175 BLK
0.5 PPL/ 178 YEL 0.5 0.5
0.5LTGRN 196 PNK/ 194 LTGRN/
WHT 0.5 PPL/ 176
GRN BLU WHT
3 5 9 6 2 C2 12 11 10 3 4
Evôrator Fan Ignition Redrculate Recirculate Temp Temp Temp Tmp Tem
23
Temperature Relay Off On 5 4 1
Input Input
(SolidState
F an F an
Fan Uled Mled
i U
5' 3 0-----
'"""2
2 BLU/RED 183 0.8 BLU/ 181
BLK 0.8 BL
0.8 BLU/ 182 WHT
\A/ YEL
D1; C10. C11.
3LTGR N191 2 BLU/RED 192 L-----01
2 BLU/RED
0.8 BL-U/ 194 0.8 BL
-<^-fM)-^>-
,
YEL WHT
192
2 BLU/R ED 193 0.8 BLU/ 195
2JI BLK 4
6. .
Blower
|
Motor ^
Heater Blower Controls Schematics (Cell 60: HVAC Mode Actuator)
HVA
,
Mod
Actu
| Chanfla Switch | ,
'-i
'1
>
11'.
1 1 1
A' C' D' H' B' F' Q' E'
0.8 BRN/BLK 227 0.8 BRN/YEL 220 0.8 BRN/WHT 223 225
0.8 LT GRN/BLK 224 0.8 BRN/BLU 226 0.8 BRN/GRN 221 0.8 BRN 222
AH, B8, B7, A7, A8, A10, ^ A12, : c212
0.5 BRN/BLK 190 0.5 BRN/YEL 199 0.5 BRN/WHT 191 0.5 BLK/QRY 197
0.5 LT GRN/BLK 198 0.5 BRN/BLU 189 0.5 BRN/GRN 200 0.5 BRN 192
''6. C1 1, C2
14, 6 5 7
8. 13. ,C1
-------' 1
H
Co
'
1' C3 10 C2 2' C1 8 4' rc2
0.8 BLK 179 0.5 BLK 186 0.5 BRN 172

0.5 BLK/RED 173
0.5 BLK 174
0 " <-
or1 OR ^^^^^^^
\^ &XS 2D^
r -
Interior
-<-
-
-.
^
Junction
'

T 'BIOCk
1
Doming
Cell 117
1 '1T)
I
L---1-J Y
i
Ground
Distribution
Cell 14
1-6 Heating and Ventilation (Non-A/C) HVAC
Component Locator
Heater Blower Controls Components

Name Location Locator View Connector End View
A/C Compressor Clutch In the engine harness, on the lower right
Heater Blower Controls
Connector Plug front of the engine, on the A/C compressor
Component Views
(w/o A/C) clutch harness
A/C Mode Switch In the center of the IP, part of the HVAC Heater Blower Controls
(w/o A/C) controller Component Views

Heater Blower Controls Heater Blower Controls
Blower Motor (w/o A/C) Behind the lower right side of the IP
Component Views Connector End Views
Blower Motor Resistor In the lower right side of the IP, part of the Heater Blower Controls Heater Blower Controls
(w/o A/C) blower motor assembly Component Views Connector End Views
In the center of the lower IP, behind the Heater Blower Controls
Blower Relay (w/o A/C)
panel, in relay center 2 Component Views

In the center of the IP, part of the HVAC Heater Blower Controls
Blower Switch (w/o A/C)
controller Component Views

HVAC Air Temperature Behind the lower right side of the IP, near Heater Blower Controls Heater Blower Controls
Actuator (w/o A/C) the blower motor assembly Component Views Connector End Views
HVAC Controller In the upper IP harness to the HVAC Heater Blower Controls
(w/o A/C) controller Component Views

HVAC Controller
In the upper IP harness to the HVAC Heater Blower Controls Heater Blower Controls
(w/o A/C) C1
controller Component Views Connector End Views
(16 cavities)
HVAC Controller
In the upper IP harness to the HVAC Heater Blower Controls Heater Blower Controls
(w/o A/C) C2
(12 cavities)
controller Component Views Connector End Views
HVAC Controller In the upper IP harness to the HVAC Heater Blower Controls Heater Blower Controls
(w/o A/C) C3 (6 cavities) controller Component Views Connector End Views
HVAC Mode Door Behind the lower right side of the IP, near Heater Blower Controls Heater Blower Controls
Actuator (w/o A/C) the blower motor assembly Component Views Connector End Views
HVAC Recirculating/Fresh Behind the lower right side of the IP, near Heater Blower Controls Heater Blower Controls
Air Actuator (w/o A/C) the blower motor assembly Component Views Connector End Views
1998 -
MD-lsuzu
Heater Blower Controls Component Views

Engine Harness to RH Side of Engine, RH Rear View
228805
Legend
(1) Engine Harness (4) A/C Compressor Clutch
(2) Generator Fuse (5) A/C Compressor
(3) Generator (6) Engine Oil Pressure Gauge Sensor
1998 -
MD-lsuzu
Instrument Panel, Left Forward View
231675
Legend
(1) HVAC Controller (5) Park Brake Switch (ABS-Air)
(2) Radio (6) Trailer Stoplamps Switch (ABS-Air)
(3) Cigar Lighter Lamp (7) Blower Switch (Part of HVAC Controller)
(4) Cigar Lighter
1998 -
MD-lsuzu
HVAC System
231683
Legend
(1) Blower Motor Resistor
(2) HVAC Recirculating/Fresh Air Actuator
(3) Blower Motor
1998 -
MD-lsuzu
Instrument Panel, Lower Right View
231681
Legend
(1) Relay Center 2
(2) Turn/Hazard Flasher Module
1998 -
MO-ISUZU
HVAC System
231686
Legend
(1) HVAC Mode Door Actuator
(2) HVAC Air Temperature Actuator
1998 -
MD-lsuzu
Heater Blower Controls Connector HVAC Air Temperature Actuator (w/o A/C)
End Views
Bl ower Motor (w/o A/C)

Blower A/C )
GO
-,01.
BI^ n]
-m
-EL. J u~B Be] ~ i
F^1
(^
L^J
B
A
a3 [5]
C
'^^^^^'
'*^^^^'
240174
> ^
5 Way
Connector Part
Information
Male
239986
Circuit
art 3 Way
Connector Pi
Part Pin Wire Color No. Function1
Function
Information
Male Temperature Acti
Actuator,
jator,
1
1 PNK/BLU
PNK/RIII 231
9-11
Circuit Temperatures5
Temperature
Pin Wire C;olor
Color No. Function
Fiunction 2
Not Used
A LTGRN
LTG RN 191 Blower Me
Motor
stor
Temperature Act
Actuator,
uator,
3 PNK 230
B BLU/FRED
BLU/RED 192 Blower Meator Resistor
Motor Temperature 4
Temperature Act
Actuator,
uator,
4 LTGRN 229
Blowerr Motor Resistor (w/o A/C) Temperature 2
Temperature Act
Actuator,
uator,
5 PNK/BLK 232
Temperature 3
LT Temperature Act
Actuator,
jator,
rrî 6
GRN/WHT
228
Temperature 1
aâ
L?]L?3L^
HVAC Controller C1 (w/o A/C)
5=^
240173
:BaBBaaaa
Connector Part 3 Way : B@0[i2]^]B@[ie]
Information
Male
Circuit
Pin Wire Color No. Function
1 BLU/ WHT 196 Fan Low Resistor
240175
2 BLU/RED 192 Blower Motor
Connector Part

16 Way
3
Not Used
Information
Male
4 BLU/BLK
Fan Mediijm Low
195 Circuit
Resistor
5 Not Used
1
Not Used
Fan Mediijm High
6 BLU/YEL 194 2 BLK 186 Ground
Resistor
3 PNK 187 Temp 4
LT
4 188 Temp 1
GRN/WHT
7995 -
MD-ISUZU
HVAC Controller C1 (w/o A/C) (cont'd) HVAC Controller C2 (w/o A/C) (cont'd)
^ ^
I I i
r-
:EB:3BBBBB EBBBBB
:B0E7|@@@@@ BBBEB@
240175 240177
Connector Part
16 Way Connector Part
12 Way
Information
Male Information
Male
Circuit Circuit
Pin Wire Color No. Function Pin Wire Color No. Function
5 BRN/BLU 189 Mode 1 4 BLK/RED 173 Rheostat
6 BRN/BLK 190 Mode 2 5 LTGRN 171 Ignition
7 BRN/ WHT 191 Mode 3 6 PPL/GRN 176 Recirculate OFF
8 BRN 192 Mode 4 7 RED/BLU 184 Ground
9
Not Used 8 BRN 172 Illumination
10 PNK/BLU 194 Temp 5 9 PPU WHT 178 Not Used

11 PNK/BLK 195 Temp 3 10 BLK 174 Ground
12 LTGRN 196 Temp 2 11-12
Not Used
13 LT GRN/YEL 197 Mode 7
HVAC Controller C3 (w/o A/(C)
14 LT GRN/BLK 198 Mode 8
15
Not Used
16 BRN/YEL 199 Mode 6
HVAC Controller C2 (w/o A/C) rî ,
c^cScS
^ L^cSa
:CTilBBBB
:B[]]BEB@ 6 Way
240180
Connector Part
Information
Male
Circuit
240177
1 BLK 179 Ground
Connector Part
12 Way
Information
2 BLU/ WHT 180 Fan Lo

Male
3 BLU/BLK 181 Fan Med Lo
Circuit
Pin Wire Color No. Function1 4 BLK 182 Fan Med Hi
1 BRN/ GRN 200 Mode 5 5 BLU/RED 183 Fan Hi
2 PPL/YEL 175 Recirculate ON 6 RED/BLU 184 Ground
3 GRN 177 Condenser Fan Control
1998 -
MD-lsuzu
HVAC Mode Door Actuator (w/o A/C) HVAC RecircuIating/Fresh Air Actuator
(w/o A/C)
ff=FI
EC all hTt hn r,r|
^J(|LJ Uil
SLF] [G] BE] as fS[ B
V J BE E B
240182
9 240183
Connector Part

Way
Information 7 Way

Male Connector Part
Information Male
Circuit
Pin Wire Color No. Function Circuit
A LT GRN/BLK 224 Mode Actuator Mode 8 Pin Wire Color No. Function
B BRN/ GRN 221 Mode Actuator Mode 5 A-C

Not Used
C BRN/BLK 227 Mode Actuator Mode 2 Recirculate/Fresh

D PPL/YEL 233
Actuator ON
D BRN/BUJ 226 Mode Actuator Mode 1
E LTGRN 236 Not Used
E LT GRN/YEL 225 Mode Actuator Mode 7
F
Not Used
F BRN/ WHT 223 Mode Actuator Mode 3
Recirculate/Fresh
G BRN 222 Mode Actuator Mode 4 G PPUGRN 234
Actuator OFF
H BRN/YEL 220 Mode Actuator Mode 6 H PPU WHT 235 Not Used
J BLK 219 Mode Actuator
Diagnostic Information and Procedures
Blower Motor Inoperative at Any Speed

Problem Action
A faulty fuse.
Determine and correct cause of the malfunction.

Refer to HVAC Blower Controls System Check.
A faulty blower motor resistor.

A faulty fan controller switch.
.
A faulty blower motor and/or
wiring.
1998 -
MD-lsuzu
Blower Motor Inoperative at High Speed Only

Step Action Value(s) Yes No
Place the blower speed switch in the failing speed
1 position.
Is HIGH speed the failing speed? Go to Step 2 Go to Step 3

Locate and repair the open in CKT 192 (BLU/RED)
2 between the blower resistor and the HVAC mode switch.
Is the repair complete? System OK Go to Step 3
1. Disconnect the connector at the blower motor

resistor.
2. Place the ignition switch in the RUN position.

3. Place the blower speed switch in the HIGH speed
position.
4. Connect a self-powered test lamp between the
3 blower motor resistor connector terminal for the
failing position and the wire and chassis ground. The

following are the failing positions:
. LOW-1
MED LOW-4

MED-HI-6
Does the test lamp light? Go to Step 4 Go to Step 5
Replace the blower motor resistor.

4
Disconnect the HVAC mode switch connector C 3

5 terminal 2 and chassis ground.
Locate and repair the open in the wire between the blower
6 resistor and the HVAC mode switch.
Replace the HVAC mode switch.

7
Is the repair complete? System OK
1998 -
MD-lsuzu
Blower Motor Inoperative at Medium Speed

1 position.
Is MED speed the failing speed? Go to Step 2 Go to Step 3


resistor.

3. Place the blower speed switch in the MED speed
position.


LOW-1
. MED LOW-4
.
MED-HI-6
4
Disconnect the HVAC mode switch connector C 3

5 terminal 2 and chassis ground.


7
1998 -
MD-lsuzu
Blower Motor Inoperative at Low Speed Only

1 position.
Is LOW speed the failing speed? Go to Step 2 Go to Step 3


resistor.
3. Place the blower speed switch in the LOW speed

position.


. LOW-1
. MED LOW-4
.
MED-HI-6

4
1. Disconnect the HVAC mode switch connector C 3.
5 2. Connect a test lamp between the connector C 3
terminal 2 and chassis ground.


7
Heating Insufficient
Poor Defrosting
Problem Action
The door(s) which control Determine and correct the cause of the malfunction.
airflow are not functioning Determine and correct the cause of the malfunction. Refer to. Blower Motor
correctly.
Inoperative at Any Speed
The blower motor is not
Remove the blockage.
working.
Flush the cooling system. Refer to. Flushing
There is blockage in the
Determine and correct the cause of the malfunction. Refer to Thermostat
defroster outlets.
Diagnosis.
A restricted heater core and/or
Clean the air conditioning filter. Refer to Passenger Compartment Air Filter
hoses.
Replacement.
A faulty thermostat and/or
Remove the blockage.
radiator cap.
There is blockage in front of the

air conditioning filter.
There is blockage in the path of
the door.
1998 -
MD-lsuzu
No Heat (Blower Motor Working)

Problem Action
There is low engine coolant 1. Check the engine coolant level. Refer to. Draining and Filling Cooling System
level. (Cooling System) in Engine Cooling.
A faulty thermostat and/or 2. Determine and correct the cause of the malfunction. Refer to. Thermostat
radiator cap. Replacement in Engine Cooling.
A restricted heater core and/or 3. Flush the cooling system. Refer to. Flushing
hoses. 4. Check the actuator function and replace as necessary.
A faulty actuator.
5. Seat the pivot shaft of the door(s) correctly.
The pivot shaft of door(s) is not Clean the air conditioning filter. Refer to Passenger Compartment Air Filter
6.
seated correctly. Replacement.
There is blockage in front of the
7. Remove the blockage.
There is blockage in the path of
the door.
Heater Gurgling Sound

Problem Action
There is low engine coolant. Check the engine coolant level. Refer to Draining and Filling Cooling System
A restricted heater core and/or (Cooling System).
hoses. Flush the cooling system. Refer to Flushing in Engine

Cooling.________
Poor Ventilation
Problem Action
A blockage in the heater Remove the blockage in the heater module.
module. Remove the blockage in the recirculating/fresh air duct.
A blockage in the
Remove the blockage, repair and replace as necessary.
recirculating/fresh air duct.
Repair and replace the door as necessary.
A binding or sticking of the
recirculating/fresh air door.
Seat the pivot shaft of the door.
Seat the pivot shaft of the door(s).
The recirculating/fresh air door
is not operating.
A faulty recirculating/fresh air
actuator.
The pivot shaft of the door is
not seated correctly.
Heat Excessive
Problem Action
The temperature door and/or Determine and correct the cause of the malfunction.
actuator are faulty. Determine and correct the cause of the malfunction. Refer to Engine
The engine is overheating.
Overheating.______________________________
1998 -
MD-lsuzu
Repair Instructions
Control Assembly Replacement
Removal Procedure
A control assembly is available from the service
parts warehouses. They are offered as a complete
assembly. This item cannot be serviced. Service is
by replacement only.
Caution: Refer to Battery Disconnect Caution in
Cautions and Notices.
1. Disconnect the negative battery cable. Refer to
Battery Replacement in Engine Electical.
2. Remove the cluster trim.
214649
3. Remove the control assembly screws.

4. Remove the control assembly.
5. Disconnect the electrical connectors.
229887
Installation Procedure
1. Connect the electrical connectors.
2. Install the control assembly.
3. Install the control assembly screws.
2298B7
1998 -
MD-lsuzu
4. Install the cluster trim.
5. Connect the negative battery cable.
214649
Blower Switch Replacement

Removal Procedure
Caution: Refer to Battery Disconnect Caution In
214649

229887
1998 -
MD-lsuzu
'==SS=\
229887
5. Connect the negative battery cable. Refer to

Battery Replacement in Engine Electrical.
214649
Blower Motor Resistor Replacement

Removal Procedure
2. Remove the assist handle bolts.
3. Remove the assist handle.
229889
1998 -
MD-lsuzu
22 Heating and Ventilation (Non-A/C) HVAC
4. Remove the instrument panel right lower trim.
214669
6. Remove the blower resistor screws.

7. Remove the blower motor resistor.
229930
1998 -
MD-ISUZU
1. Install the blower motor resistor.
229930
2. Install the blower motor resistor screws.

229897
4. Install the instrument panel right lower trim.
214669
1998 -
MD-lsuzu
5. Install the assist handle.
6. Install the assist handle bolts.

229889
Blower Motor and Fan Replacement

Removal Procedure
Caution and Notices.

229889
214669
1998 -
MD-lsuzu

6. Remove the blower motor cooling tube.
7. Remove the blower motor screws.
8. Remove the blower motor and fan.
1. Install the blower motor and fan.
229931
1998 -
MD-lsuzu
2. Install the blower motor screws.

3. Install the blower motor cooling tube.
229897
214669

229889
1998 -
MD-ISliZtl
Air Distributor Duct Replacement (Lower)

Removal Procedure
2. Remove the instrument panel. Refer to

IP Carrier Replacement Instrument Panel and
Gauges.
3. Remove the air distributor duct lower screws.
4. Remove the air distributor duct lower bolt.
5. Remove the air distributor lower duct.
229904
1. Install the air distributor lower duct.
2. Install the air distributor lower duct bolt.

3. Install the air distributor lower duct screws.
4. Install the instrument panel. Refer to IP Carrier
Replacement Instrument Panel and Gauges
229904
1998 -
MD-lsuzu
!8 Heating and Ventilation (Non-A/C) HVAC
Air Distributor Duct Replacement (Upper)

Removal Procedure

IP Carrier Replacement in Instrument Panel and
Gauges.
3. Remove the air distributor upper duct screws.
4. Remove the air distributor upper duct.
1. Install the air distributor upper duct.
2. Install the air distributor upper duct screws.

Replacement in Instrument Panel and Gauges.
229918
Air Inlet Actuator Replacement

Removal Procedure
229889
7998 -
MD-ISUZU
214669
229897
1998 -
MD-lsuzu
229904
7. Remove the air inlet actuator.
229948
1998 -
MD-lsuzu
1. Install the air inlet actuator.
229948
229904
1998 -
MD-ISUIU
229897
214669

229869
1998 -
MD-ISUZU
Temperature Actuator Replacement

Removal Procedure

229889
214669
229897
1998 -
MD-lsuzu
229904
7. Remove the temperature actuator.
229948
7998 -
MD-ISUZU
1. Install the temperature actuator.
229948
229904
199B -
MD-lsuzu
229897
214669

229689
1998 -
MD-lsuzu
Mode Actuator Replacement

Removal Procedure
229889

4. Remove the instrument panel lower trim.
214669
5. Disconnect the audio system. Refer to Radio

Replacement in Entertainment.
229897
1998 -
MO-lsuzu
38 Heating and Ventilation (Non-A/C) HVAC
229904
7. Remove the heater module (right side).
229927
1998 -
MD-lsuzu
8. Remove the mode actuator.
229907
1. Install the mode actuator.
229907
2. Install the heater module (right side).
229927
1998 -
MD-lsuzu
229904
4. Connect the audio system. Refer to Radio

229897
1998 -
MD-lsuzu
5. Install the instrument panel lower trim.
214669

229889
Heater Pipes Replacement (Inlet)

Removal Procedure
1. Drain the engine coolant. Refer to Draining and
Filling Cooling System (Draining) in Engine
Cooling.
2. Remove the inlet hose clamp to the engine pipe.
3. Remove the hose clamps from the heater core.
4. Remove the inlet pipe mounting bolts, washers
and nuts.
290969
1998 -
MD-lsuzu
5. Remove the inlet pipe clamp on the frame.
290969
Important:
If replacing the heater inlet connector (1), it is
located on the engine, remove the retainer (4)
from the hose and discard. The new
connector is equipped with a retainer. (4)
If replacing the heater inlet hose, (5) remove
the retainer (4) from the heater inlet hose and
^
reinsert in the connector. (1)
If reusing the hose (5) and connector, (1) the
retainer (4) can remain in heater inlet place on
the hose.
6. Remove the inlet pipe.
220038
Notice: Refer to Fastener Notice in Cautions and
Notices.
1. Push the pipe into the heater inlet hose
connnector (1) until the retainer locking tabs
lock (2, 3). Pull back on the hose to check for
^ proper engagement.
Tighten
Quick connect heater inlet connector to 35 N.m
(26 Ib ft).
220038
1998 -
MD-ISUZU
2. Install the inlet pipe.
290969
3. Install the pipe clamps on the frame.

4. Install the inlet pipe mounting bolts, washers
and nuts.
5. Install the inlet hose clamp from the heater core.
6. Install the inlet hose clamp to the engine pipe.
7. Fill with engine coolant. Refer to Draining and
Filling Cooling System (Filling) in Engine Cooling.
8. Inspect the system for leaks.
290969
Heater Pipes Replacement (Outlet)

Removal Procedure
Cooling.
2. Remove the hose clamp from the heater core.

3. Remove the hose clamp from the radiator hose.
4. Remove the mounting bolt.
1998 -
MD-lsuzu
5. Remove the pipe clamp on the frame.
291029
6. Remove the outlet pipe.
Installation procedure
1. Install the outlet pipe.
290964
1998
MD-lsuzu
2. Install the clamp on the frame.
3. Install the mounting bolt.
4. Install the hose clamp from the radiator hose.

5. Install the hose clamp from the heater core.
291029
Heater Core Replacement (Right)

Removal Procedure
1. Raise the hood and support.
Cooling.
3. Remove the windshield wiper right link.

4. Remove the heater hose clamps.
5. Remove the heater hoses.
229937
1998 -
MD-ISUZU
6. Remove the heater core cover plate screws.

7. Remove the heater core cover plate.
8. Remove the heater core screw.
229939
9. Remove the right heater core.
229941
1. Install the right heater core.
2. Install the heater core screw.

3. Install the heater core cover plate.
229941
1998 -
MD-lsuzu
4. Install the heater core cover plate screws.
229939
5. Install the heater hoses.

6. Install the heater hose clamps.
7. Install the windshield wiper right link.
10. Close the hood.
229937
Heater Core Replacement (Left)

Removal Procedure
Cooling.
229937
1998 -
MD-lsuzu

229939
9. Remove the left heater core.
229941
1. Install the left heater core.
229941
1998 -
MD-lsuzu
229939

Filling Cooling System (Filling) in Engine
Cooling.
10. Close the hood.
229937
1998 -
MD-lsuzu
Heater/Vent Module Replacement

Removal Procedure

IP Carrier Replacement in Instrument Panel and
Gauges.
3. Remove the right heater core. Refer to Heater
Core Replacement (Right).
4. Remove the A/C Tempature Sensor connectors
screw.
5. Remove the left heater core. Refer to Heater
Core Replacement (Left).
6. Disconnect the A/C Tempature Sensor
connectors electrical connectors.
229927
7. Remove the A/C Tempature Sensor connectors.
8. Remove the air conditioning evaporator. Refer
to Evaporator Core Replacement.
9. Disconnect the blower motor resistor electrical

connectors.
10. Disconnect the blower motor electrical connectors.
11. Remove the heater vent module nuts.
12. Remove the right heater vent module.
13. Remove the left heater vent module.
229929
1998 -
MD-ISUZU
1. Install the left heater vent module.
229929
2. Install the right heater vent module.

3. Install the heater vent module nuts.
4. Install the blower motor electrical connectors.
5. Install the blower motor resistor electrical
connectors.
6. Install the air conditioning evaporator. Refer to
Evaporator Core Replacement.
7. Install the A/C Tempature Sensor connectors.
8. Connect the A/C Tempature Sensor connectors
electrical connectors.
9. Install the A/C Tempature Sensor connectors

screw.
10. Install the heater cores. Refer to Heater Core
Replacement (Right).
Battery Replacement in Engine Electrical. 229927
1998 -
MD-ISUZU

Heater System Description
229842
Hot coolant comes from the engine and is directed Outside air is drawn from the plenum into the heater
through the heater cores (6) and returned to the vent module by the blower motor fan (3). Additional
cooling system when the engine is running (under outside air (called ram air) is forced into the heater
normal operating conditions). vent module by the forward movement of the vehicle
The heater vent module contains components that and goes to the outside air inlet (5). Within the
heat the air flowing through. The heater vent module heater vent module, the air is heated as required,
directes air to the proper ducts and outlets such as then routes through ducts to the proper outlets for
the distributor duct (upper) (1), the insturment panel discharge into the passenger compartment. A control
outlets (2), and the floor vents (7). assembly in the instrument panel allows the operator
to control the following conditions:
The heater system provides the following features:

Blower speed

Heated ram air

Mode of operation

Power ventilation

Temperature of the air coming from the heater
Windshield defrosting
system
1998 -
MD-lsuzu
Air Distribution System Description
229843
Within the heater vent module is a series of air doors are hinged parts that direct the airflow through
doors the inlet air door (1), the temperature actuator the various sections of the heater vent module in
door (2), and the mode actuator door (3). These air order to provide the proper airflow for the selected
operating mode.
229846
Each air door is controlled by an actuator either the routing the blower motor ground through dropping
mode actuator (1), the inlet air actuator (4) or the resistors. The blower motor speed switch supplies
temperature actuator door (5). ground through one of the resistors for all speeds
but HIGH.
Heater Blower Controls Circuit Description With the blower motor switch in the LO position,
Blower Motor voltage is applied from the switch contacts through
the BLU/WHT (180,196) wire to the blower motor
The blower motor controls operate by supplying
resistor. The blower motor current flows through all
ground to the motor through the blower speed switch
three resistors in this switch position. The grounding
contacts through the blower resistor. Battery voltage is provided through the switch common terminal
is available to the blower relay coil from Circuit
through the HVAC controller module. Current flow is
Breaker #6 when the ignition switch is in the RUN established at which point the blower motor
position through the BRN (198) wire. Relay contact
operates. Voltage drop through the three resistors in
power is provided by Circuit Breaker #24 for the the blower motor resistor limits motor operation to its
operation of the blower motor any time the ignition is lowest speed.
in the RUN position. Motor speed is controlled by
1998 -
MD-lsuzu
With the blower motor switch in the MED LO HVAC Temperature Actuator
position, voltage is applied to the blower motor
The HVAC temperature actuator controls the amount
resistor through the BLU/BLK (181, 195) wire. of engine coolant available to the heater core. The
Current flows through only two resistors to get to the
operator heat selection lever position is translated
motor. The motor operates at a faster speed than into an electric signal. The temperature actuator
through all three resistors.
controls a motor operated valve in the engine
With the blower motor switch in the MED HI position, coolant line. The valve is driven open in order to
voltage is applied to the blower motor resistor provide more heat energy (or closed for less heat) in
through the BLU/YEL (182/194) wire. Current flows response to the operator temperature selection.
through only one resister to get to the motor. With
the increased voltage at the motor, the motor
operates at a still faster speed.
With the blower motor switch in the HI position,
voltage is applied directly to the blower motor
through the BLU/RED (183/192) wire. Current flows
directly to the motor. With the maximum voltage at
the motor, the motor operates at the fastest speed.
Modes Description
( )( K X X I
^ ^

^ <S)

()()
(51 A/C
^
( COLDC )HOT 1
^ ^-^^ 4.
"
OFF
1234 )
\-
<=^D==3 H " -

-~
'
}
y
229857
The control assembly in the instrument panel Temperature Lever

contains the following components:
When the temperature lever (5) is in the COLD or
A blower switch extreme left end of the slot, all of the air delivered
Mode switches by the heater system is unheated. The temperature
A temperature lever actuator and the temperature control door are
positioned to stop all of the airflow through the
The controls are lit when the headlamps are on.
heater cores so only unheated air is sent up in the
Electrical power is provided by the control panel
heater module.
lighting circuit from the control panel harness.
When the temperature lever is in the HOT or
The mode control switches allow the driver to control
extreme right end of the slot, almost all of the air
the direction and quantity of air through different
delivered by the system is heated. The temperature
outlets.
actuator and the temperature control door is
Brightness of the illumination is controlled by the positioned to open so that all of the airflow through
instrument panel dimmer switch. The control the heater cores is sent up in the heater vent
assembly bulbs are in parallel with the radio bulb module.
and the instrument cluster illumination bulbs.
Intermediate positions of the temperature lever result
in a mixture of heated and unheated air to provide
Fan Control Switch
more moderate air temperatures. This lever operates
Air quantity is controlled by the four-position blower
the temperature actuator. As a result, this lever
fan (4) control switch. The blower fan control switch
moves the temperature control door.
provides a choice of various blower motor speeds.
1998 -
MD-lsuzu
Vent Mode Defrost Mode

With the vent switch (6) in the ON position, the inlet With the Defrost switch (1) in the ON position, the
air actuator is activated. This causes the mode actuator is activated. This causes the mode
recirculating/fresh air door to open completely and air control door to open completely. The majority of the
is discharged from the upper air outlets. As a result, airflow is routed to the windshield outlets while the
the air coming from the upper air outlets should be remaining airflow is routed to the floor.
nearly the same temperature as the outside air.
Max/Rec/Rc Mode
Bi-Level Mode With the Max /Rec/ Re switch (2) in the ON position,
With the Bi-Level switch (7) in the ON position, the the air inlet actuator is activated. This causes the air
mode actuator is activated. This causes the mode inlet door to close completely, causing very little
control door to open halfway. The airflow is divided outside air (that is needed for the outside air system)
between the upper air outlets and the floor air from coming in. The majority of airflow is not outside
outlets. air. The air is recirculated throughout the cab.
Floor Mode A/C Mode

With the Floor switch (8) in the ON position, the With the A/C switch (3) in the ON Position, the air
mode actuator is activated. This causes the mode conditioning will work.
control door to open completely. The majority of
airflow is routed to the floor while the remaining
airflow is routed to the windshield outlets.
Floor/Defrost Mode
With the Floor / Defrost switch (9) in the ON
position, the mode actuator is activated. This causes
the mode control door to open halfway. Half of the
airflow is delivered to the floor while the other half is
delivered to the windshield outlets.
1998 -
MD-ISUZU
BLANK
1998 -
MD-lsuzu
HVAC HVAC Systems with A/C -
Manual 1-57
HVAC Systems with A/C -

Manual
Specifications

Specification
Compressor Hose Block Fitting Bolt 35N.m 26lbft
Compressor Mounting Bracket Bolt 39N.m 29lbft
Condenser Brace Lower Nut 70N.m 51 Ibft
Condenser Insulator Bracket Nut 24N.m 18lbft
Condenser Insulator Nut 35N.m 26lbft
Condenser Tube to Receiver/Dryer or Dehydrator Fitting 15N.m 11 Ibft
Evaporator High Pressure Hose Fitting at Condenser 18N.m 14 Ibft
Evaporator Hose Bracket Nut 30N.m 22 Ibft
Evaporator Hose Clamp Nut 30N.m 22 Ibft
Evaporator Low Pressure Hose Fitting at Evaporator 32 N.m 24 Ibft

Expansion Valve Fitting 20N.m 15 Ibft
Expansion Valve Low Pressure Fitting 15 N.m 11 Ibft

Fan Drive Support Assembly Nut 45 N.m 33 Ibft
Refrigerant Hose Clamp Nut 30N.m 22 Ibft
Refrigerant Hose Fitting at Condenser 23 N.m 17 Ibft
Refrigerant Hose Fitting at Evaporator 32 N.m 24 Ibft
Armature Bolt 13 N.m 113lbin
Field Coil Screw 5 N.m 44lbin
Compressor Specifications
Compressor Information Data
Armature Clearance 0.3 -
0.6 mm (0.01 -
0.02 in)
Compressor Model 7 Zexel DKS-17CH
Cylinder Type 6 Cylinder Axial
Rotation Clockwise
Oil R-134a Swash Plate P/N AIPDN 2-90188-300-0 refrigerant oil
System Capacities
Specification
Refrigerant-134a 0.9072 kg 2.0 Ib
1998 -
MD-lsuzu
1-58 HVAC Systems with A/C -
Manual HVAC
Refrigerant Oil Distribution Specifications

Specification
R134-a Swash Plate P/N AIPDN 2-90188-300-0 Refrigerant Oil
Zexel DKS-17CH Compressor 196ml 6.6 fl oz
Evaporator 50.2 ml 1.7floz
Condenser 29.6 ml 1.0 fl oz
Receiver/Dryer Dehydrator 8.9ml 0.3 fl oz

Refrigerant Hose 8.9ml 0.3 fl oz
HVAC Schematic References

Subsection Name
Interior Lamps Dimming Cell 117 8Lighting Systems
Wiper/Washer: Pulse Cell 91 8Wiper/Washer Systems
HVAC Schematic Icons

Icon Icon Definition
Refer to SD Notice in Cautions and Notices.
A^ 19384
1998 -
MD-ISUZU
HVAC Blower Control Schematics (Ceil 63: HVAC Compressor and Condenser Fan Contro
Hoi hi RUN And START 1 iHot Al All Timest tHotAtATim<>*1
Ip
- -
[
-1
CIreuM Chcult circuit

*
^Breaker 'Fuse
\Broaker ^ JT^ [Block
6 /24
/
15 A 15 A ISA ,
2BRN 371 2 GRN/RED, 201 S304 8XXX

8227
2 LTGRN 210
2BRN 371 2 LTGRN 204
'8279 2 GRN/RED 201 2 GRN/RED 27
1 2BRN 371 30,. 85. 1 301 e5.
1
"
8280 Condenser <- -AC

1 1 r------< 2BRN 337 :
Fan
; :
Compressor
E Relay Relay
8281
/: ---.-i\ /-- ----4 ^ <
tttt
fuse bock
Details
2BRN 198
8282
LTGRN 190
'
86'
1.2
Cell 11
87 87 '0.8 86'
2BRN 198 1.25 GRN/RED 911
o
'85 [ aa. I:"--'Relay WHT
LT GRN/ 205
2 LT BLU 208 0.8 GRN/ GR
RED C211 RED
Relay 1^2 2BLK/WHT 202 8307 <
213 6 18
\ ! 30
v
28
I
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-
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-
--^ 27 ,C200
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S------S 0.8
J's.T 87 0.8 DK 0.8 LT BLU 203 QRN/ 211
GRN/WHT 1728 RED 0.8
0.8 BLK 199 0.8 DK
8341 BLU/WHT 1727
B, A, ,C107 B
1 6 Diode
0.8 BLK 14 0.8 LT BLU 203
1 r
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Module 0.8
1 | /
1.25 BLK 164 2 LT GRN 204 ,\ Conden
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ser
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3 BLK 21 Motor 0.8 DK
GRN/WHT 1728 RED Wloer Sy
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Distribution '8323 2 212
Cell 14
.-< 3 3^
3 BLK 21 AC t T High -
Low
-' LTGRN 191 p'reSSUre / Pressure / Pressure 6 C116
'8325 0.8 BLK 150 C^CutOff
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Distribution ^- - - -
-. '83283 Distribution '8103

>-
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DK GRN KfiRN 59
59 D KGRN w
Cell 14 3 BLK
3 ^200LTGRN
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SP100 C C107 P100
3 BLK 550 r- 7 v
$ 0.8 DK GRN C200 "^ 1
LG105 \y LG107 603 29
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2
HVAC Blower Control Schematics (Cell 63: HVAC Blower and Temperature Controls)
M
~
HVAC T
1^1 A
Recirculate/
J^
.. ^ fange
|
^F 1y a witch Fresh Actuator
6'
1.25 QRN 216
E11, ,C212 2
E"'"""H^
LTGRN 236
G D
- 4' 5'
0.8 PNK/ 232
w
1'
-8
3'
PNK 230
I
0.8 PPL/ 235 BLK
.WHT 0.8 PPL/ 234 0.8 0.8
2LT 3RN GRN 0.8 LT GRN 229 PNK/ 231 LT GRN/ 22
oouo 0.5 PPL/ 233
'
197 BLU WHT

YEL
2 LT GRN 197 B10; C7^ B9' C
'
Bi2^ Bil
D11, B6, C9, C8, ,C212 -5
0.5 GRN 177 0.5 PNK/ is>
195
p^K 187
1.25LTBRN 171 0.5 PPL/ 175 BLK
0.5 PPL/ 178 YEL 0.5 0.5
0.5 PPL/ 176 0.5 LTGRN 196
PNK/ 194 LT GRN/ 18
WHT
GRN BLU WHT
3 5 9 2 C2 12 11 10 3 4 ,C1
6,
Evaporator Fan Ignition Redrculato Radrculate Temp Temp Temp Teinp Temp
23
Temperature Relay Off On 5 4 1
Input Input
[8o8dSta!e'
F an F an
Fan ktad Mtod F
HI Hi Uo L
5' '"""4 '------3----------2

BLU/181
2 BLU/RED 183 0.8
BLK 0.8 BLU/
0.8 BLU/ 182 WHT
Y D1;
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C10. . C11^
.Cl2^
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2 BUJ/RED 192
2 BLU/RED
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,
WHT
2 BLU/R ED 193 0.8 BLU/ 195
2,
1 BLK
6.
4JI 1<
Blower
|
Motor
z
HVAC Blower Control Schematics (Cell 64: HVAC Mode Door Actuator)
JJL
h-IVAC
riSTi hôde Door
o1 f-\ctuator
| ChangeSwitch |
A '
C' r DTr HT BY F'

G'
'
E
'
B.
0.8 0.8 0.8 1
--Splice
LT 0.8 'Pack #3
BRN/ 226 BRN/ 221 BRN l ,
222 <>
GRN/ 224 BLU GRN 1
BLK 0.8
0.8
BRN/ 220 0.8 0.5 LT 22 5
BRN/ 227 BRN/ 223 GRN/ A'
BLK YEL
WHT GRY
AH r B8' B7'3 A12 ;C
212 1.25 BLK/ORN 160
Ar A(T AW r A9!
0.5 0.5
0.5 BRN 192
0.5 BRN/ 189 BRN/ 200
LT GRN/ 198
BLK
BLU
0.5
QRN
0.5 LT 19-7 0.8 BLK/ORN 161
F12; ;C212
-
0.5 0.5
BRN/ 190
BRN/ 199 BRN/ 191 GRN/ 2 BLK 26
YEL WHT GRY
BLK
14 6 5 16. C1 8 13 C-1
1. ,C2 7.
r
Mexto M ode Mode'1 AC Conditioning
Mode Mode Mode Mode Mode S323
347
8 2 1 8 5
Mode Switch
1
Qround
2 BLK 68 Distribution
|SodState) Cell 14
T
8325 < i. - - - - - j
0.8 BLK 179

r C3 10 C2
0.5 BLK 186

2-C1 g,,-----
'5 BRN 172
IC2 2 BLK 720
1
0.5BLK/RED[
173
0.5 BLK 174
'*"
C, B. D-.
i-------.splice Interior
Lamps Dimming
..!Pack# 2
: r
CeH7
AT
"Sround
Distribution
Cell 14
HVAC Compressor Control Schematics (Cell 63: HVAC Compressor and Condenser Fan Con
Hot In RUN And START | |Hot At AH Times ( ["HotAt All Times |
r"i Circuit
^Breaker
15A
*
/24
1
Circuit
Breaker
15A
r-~ --- ipFuse
l circuit
j^ 15A
Block
2BRN 371 2 GRN/RED, 201 S304 8XXX

8227 '(i
8233 < 2 LT GRN 210
2BRN 371 2 LTGRN 204
S279 2 GRN/RED 201 2 GRN/RED 2207
85, I 301
1 2BRN 371
30, 85.
1 >S280 Condenser -AC
r------(

11
2BRN 337 Fan Compressor
S281
^ : Relay : Relay
tttt 2BRN
Fu^btock
198
LT GRN 190 ^ f
/. 1.2
Details
Cell 11 <---<
2BRN
8282
198
87'
f 1.25
86< 87' 0.8
GRN/RED ?11
86'
08
''"'1I Relay LTGRN/ 205
0.8GRN/ GRN
3a, 2 LT BLU 208
k
I WHT
Center RED cm RED
Relay I
#2 2BLK/WHT 202 8307 <
213 6 18
30 28 C200 * SP100
' .
L-:;:---4^P100 27. ,0200
0.8
L8^ 87' 0.8 DK a8LTBLU 203 GWf
0.8 DK GRN/WHT 1728 RED 0.8
0.8 BLK 199
S341 BLU/WHT 1727 B; B
A, ,C107
I 0.8 BLK 14 Diode
6, 0.8 LT BLU 203
'8340 Module 0.8
h-AC "
D200
I
1 A
I r
A
1.25 BLK 164
iS339
21LTGRN 204
5
i
7\
"J
Conden ser
Fan
0.8 DK
C 0.8 GRN/
3 BLK 21 Motor
Ground ]
GRN/WHT 1-728
Distribution > - -<
iS323 5, 212 CeN91
Cell 14 2, 3^
3 + .
3 BLK 21 AC Low T High
LTGRN 191 p reSSUre / Pressure 7 Pressure 6 C116
0.8 BL K 150
-.-ôff <...^cut0ff
>S325 !;
Cut Off 2GRN
1
,:
8witch'f-'
^,
3 BLK 21 S306<
Ground Ground 0.8
Distribution
Cell 14 -----(
3 BLK
'83283 Distribution ^ -
8103 DK GRN 59 DKGRN 59 -^( >
S200LTGRN
191 CelU
3, 2 LTGRN 197 0.8 DK GRN 603
0.8 BUK 150
SP100
3 BLK 550
C
^
C107
0.8 DK GRN C200 ^ 1
IG105 \7
T- ^7 LG107 603
w
2
29
HVAC Compressor Control Schematics (Cell 63: HVAC Blower and Temperature Controls
M
-
HVAC T
Redrculate/
c^ A
J^
hange|
lawitch |
^7 ^7 Fresh Actuator
1.25 GRN 216 - 4! 5' 1" 3' 6t

E H G D -8
E11, ,C212 2 LTGRN 236 0.8 PNK/ '-32
239
PNK 230
BLK
0.8 PPL/ 235
WHT 0.8
2LT GRN 0.8 PPL/ 234 0.8
GRN 0.8 LT GRN 229 PNK/ 231
LTGRN/ 22
197 OOUu 0.5 PPL/ 233 BLU WHT
YEL
2 LTGRN 197 B10 07^ f'B12f-Bil^ B9- ;C2
011, B6, C9, C8, .C212 0-5
0.5 GRN 177 0.5 PNK/ 1Q-S
195
1.25>LTBRN 171 0.5 PPL/ 175 BLK p(^ 187
0.5 PPU 178 YEL 0.5 0.5

0.5 LTGRN 196 PNK/ 194 LT GRN/ 18
WHT 0.5 PPL/ 176
GRN BLU WHT
3 5 9 6 2 C2 12 11 10 3 4 C1
Evaporator Fan Ignition Redrculate Racirculata Temp Temp Temp Teimp Temp
23
Temperature Relay Off On 5 4 i
Input Input
[SolidState
F an F an
Fan Mtod Mled F
Hi H1 U ^
5' 4 3 ---------3
2 BLU/RED 183 0.8 BLU/ 181
BLK 0.8 BLU/
0.8 BLU/ 182 WHT
3LTGRIN
T 191
D1;
YEL
2 BLU/RED 192
C10. C11.
.-----P12
2 BLU/RED
0.8 BL-U/ 194 0.8 BLU/
-, .fi?"-
Tf
-
WHT
^- 192 YEL
2 BLU/R ED 193 0.8 BLU/ 195
BLK
2\ 6. >
4. 1.>
Blower
|
Motor ^
HVAC Compressor Control Schematics (Cell 64: HVAC Mode Door Actuator)
Jl I-HVAC
r -fMl
1^1
Kôde Door
/Actuator
| ChangeSwttch |
A
'
C' r DIr HY Bf
'
F' Q' E B.
0.8
LT
0.8
BRN/ 226
0.8
BRN/ 221 0.8 ;---'Pack
splice
, #3
BRN 222 1
GRN / 224 (
BLU GRN 1
BLK 0.8
0.8
BRN/ 220 0.8 0.5 LT 22 5
BRN/ 227 BRN/ 223 GRN/ A'
BLK YEL
WHT GRY
A1 1; B85 B7'' r
A7^ A8^ 'A10^ f A12 ;C
212 1.25 BLK/ORN 160
^T

0.5 0.5
0.5 BRN 192
0.5 BRN/ 189 BRN/ 200 F12; -C212
LTGRN / 198 BLU GRN
BLK
0.5
0.5 0.5 0.5 LT 19 7 0.8 BLK/ORN 161
BRN/ 190 BRN/199 BRN/ 191 GRN/ 2 BLK 26
YEL WHT GRY
BLK
6 5 8 13
r
14 16.C1 1. lC2 7\ n-1
Mode"" AC Conditioning
Mode Mode Me wh Mode Mode S323
347
8 2 1 6 5
Mode Switch
A
QrounT
2 BLK 68 Distribution
|Sold Statoj Cell 14
T
S325< .-
-j
2 BLK 720
r C3 10 C2 2'C1
'5
y..........
BRN 172
^
0.8 BLK 179

0.5 BLK 186 BLK/RED|173
0.5
0.5 BLK 174
^
C, B. D.>
1 ;- ----'Splice Interior
Lamps Dimming
,'Pack# 2 Ce117
L
^
Ground
Distribution
Cell 14
Manual 1-65
Component Locator
HVAC Components
A/C Compressor On the lower right front of the engine HVAC Component Views
On the lower right front of the engine, on

HVAC Connector
A/C Compressor Clutch the front of the A/C compressor, behind the HVAC Component Views
End Views
pulley, part of the A/C compressor
In the center of the lower IP, behind the
A/C Compressor Relay HVAC Component Views
panel, in relay center 2
On the upper left rear of the A/C

A/C Condenser Fan
condenser fan shroud, in the lower right HVAC Component Views
Capacitor
front of the vehicle
A/C Condenser Behind the A/C condenser, in the lower HVAC Connector
HVAC Component Views
Fan Motor right front of the vehicle End Views
A/C Condenser In the center of the lower IP, behind the
Fan Relay panel, in relay center 1

A/C Mode Switch In the center of the IP, part of the HVAC
(w/ A/C) controller

In the right front of the vehicle, behind the
A/C Pressure Cutoff HVAC Connector
front bumper, on the top of the A/C HVAC Component Views
Switch End Views
condenser receiver/dryer
HVAC Connector
A/C Temperature Sensor In the A/C evaporator housing HVAC Component Views
End Views
HVAC Connector
A/C Temperature Switch In the A/C evaporator housing HVAC Component Views
End Views
HVAC Connector
Blower Motor (w/ A/C) Behind the lower right side of the IP HVAC Component Views
End Views
Blower Motor Resistor In the lower right side of the IP, part of the HVAC Connector
(w/ A/C) blower motor assembly End Views
In the center of the lower IP, behind the HVAC Component Views
Blower Relay (w/ A/C)
panel, in relay center 2

In the center of the IP, part of the HVAC
Blower Switch (w/ A/C) HVAC Component Views
controller
HVAC Air Temperature Behind the lower right side of the IP, near HVAC Connector
Actuator (w/ A/C) the blower motor assembly End Views
HVAC Controller
In the center of the IP, above the radio HVAC Component Views
(w/ A/C)
HVAC Controller In the upper IP harness to the HVAC HVAC Connector
(w/ A/C) C1 (16 cavities) controller End Views
HVAC Mode Door Behind the lower right side of the IP, near HVAC Connector
Actuator (w/ A/C) the blower motor assembly End Views
HVAC Recirculating/Fresh Behind the lower right side of the IP, near HVAC Connector
Air Actuator (w/ A/C) the blower motor assembly End Views
1998 -
MD-lsuzu
>6 HVAC Systems with A/C -
Manual HVAC
fAC Component Views

228805
gend
1998 -
MD-lsuzu
Manual 1-67
228805
Legend
1998 -
MD-lsuzu
Manual HVAC
231681
Legend
(1) Relay Center 2
1998 -
MD-ISUZU
Manual 1-69
A/C Condenser
231530
Legend
(1) A/C Condenser Fan Motor
(2) A/C Pressure Cutoff Switch
1998 -
MD-lsuzu
Manual HVAC
231681
Legend
(1) Relay Center 2
1998 -
MD-lsuzu
Manual 1-71
231675
Legend
(4) Cigar Lighter
1998 -
MD-lsuzu
Manual HVAC
A/C Condenser
231530
Legend
(1) A/C Condenser Fan Motor
(2) A/C Pressure Cutoff Switch
1998 -
MD-ISUZU
Manual 1-73
HVAC System
231683
Legend
(1) Blower Motor Resistor
(2) HVAC Recirculating/Fresh Air Actuator
(3) Blower Motor
7993 -
MD-ISUZU
Manual HVAC
HVAC System
231686
Legend
(1) HVAC Mode Door Actuator
(2) HVAC Air Temperature Actuator
1998 -
MD-lsuzu
Manual 1-75
HVAC Connector End Views A/C Temperature Switch
A/C Condenser Fan Motor
CD
A
^
[as] \T
240168
Connector Part 3 Way

240166
Information
Female
Connector Part

12162890
Circuit
Information
ASM 2F (Black) Pin Wire Color No. Function
Circuit A GRN/ RED 18 Thermo Switch
Pin Wire Color No. Function B GRN/ YEL 17 Thermo Switch
Air Conditioning
C LTGRN 16 Thermo Switch
5 DKGRN 59 Compressor Clutch
Solenoid Feed
B lower Motor (w/ A/C )
6 BLK 150 Ground
A/C Refridgerant Pressure Switch

,
n=n .
r B I
l& />
239986
3 Way
Connector Part
240167
Information
Male

12162929 Circuit
Connector Part
Information ASM 4F 090 SLD (Natural)
A LTGRN 191 Blower Motor
Circuit
Pin Wire Color No. Function B BLU/RED 192 Blower Motor Resistor
Air Conditioning
1 DKGRN 603 Refrigerant Low Pressure
Cut Out Switch Output
Air Conditioning
DK
2 1728 Condenser Relay
GRN/WHT
Output Coil
Air Conditioning
3 LT BLU 203 Refrigerant High Pressure
Cut Out Switch Feed
Air Conditioning
4 LT GRN/BLK 59 Compressor Clutch
Solenoid Feed
1998 -
MD-lsuzu
Manual HVAC
Blower Motor Resistor (w/ A/C) HVAC Air Terrnperature Actuator (w/ A/C)
(cont'd)
^
. > |T=T1
^[IhES [ l^-TT-L
-m
L"J
C^CSCS [i B B
J
\-
240173
6 240174
Connector Part

Way
Information
Male Connector Part 6 Way
Circuit
Information
Male
Pin Wire Color No. Fljnction Circuit
1 BLU/ WHT 196 Fan Low Resistor Pin Wire Colo r No. Functior1
2 BLU/RED 192 Blower Motor Temperature Act uator,
4 LTGRN 229
Temperature 2
3 Not Used
5 PNK/BLK Temperature Act uator,
4 BLU/BLK 195 Fan Middle Low Resistor 232
Temperature 3
5
Not Used LT Temperature Actuator,
6 228
6 BLU/YEL 194 Fan Middle High Resistor GRN/WH1 Temperature 1
HVAC Air Temperature Actuator (w/ A/C) HVAC Controller C1 (w/ A/C)
^
B==B 1 1
C-r-CEELri
L ll BBBBBB
V
3S
C B
J
-W
:BE [nB@E@@
240174 240175
6 Way 16 Way
Connector Part Connector Part
Information
Male Information
Male
Circuit Circuit
Temperatu re Actuator, 1
Not Used
1 PNK/BLU 231
Temperatu re 5 2 BLK 186 Ground
2
Not Used 3 PNK 187 Temp 4
Temperature Actuator, LT
3 PNK 230 4
Temperature 4 188 Temp 1
GRN/WHT
1998 -
MD-lsuzu
Manual 1-77
HVAC Controller C1 (w/ A/C) (cont'd) HVAC Controller C2 (w/ A/C) (cont'd)
5==?
5=^
11
:BB[aJBBB BB :BBBE3BB
:B@Ei]@@B @@ :BBBE o] [12] n
240175 240177
Connector Part 16 Way Connector Part 12 Way

Information
Male Information
Male
Circuit Circuit
5 BRN/BLU 189 Mode 1 4 BLK/RED 173 Rheostat
6 BRN/BLK 190 Mode 2 5 LT GRN 171 Ignition
7 BRN/ WHT 191 Mode 3 6 PPL/GRN 176 Recirculate OFF
8 BRN 192 Mode 4 7 RED/BLU 184 Ground
9
Not Used 8 BRN 172 Illumination
10 PNK/BLU 194 Temp 5 9 PPL7 WHT 178 Not Used
11 PNK/BLK 195 Temp 3 10 BLK 174 Ground
12 LTGRN 196 Temp 2 11-12
Not Used
13 LT GRN/YEL 197 Mode 7
HVAC Connector C3 (w/ A/C;)
14 LT GRN/BLK 198 Mode 8
15
Not Used
16 BRN/YEL 199 Mode 6
r~i
HVAC Controller C2 (vw/A/C)
[SCSES
:B[3BE
5=^
4. 5 B
aaa
:a[3BE 0 11 |12|
Connector Part
6 Way
240180
Information
Male
Circuit
240177
1 BLK 179 Ground
Connector Part
12 Way
Information
2 BLU/ WHT 180 Fan Lo

Male
3 BLU/BLK 181 Fan Med Lo
Circuit
Pin Wire Color No. Function 4 BLK 182 Fan Med Hi
1 BRN/ QRN 200 Mode 5 5 BLU/RED 183 Fan Hi
2 PPUYEL 175 Recirculate ON 6 RED/BLU 184 Ground
3 GRN 177 Condenser Fan Control
1998 -
MD-ISUZU
1 -78HVAC Systems with A/C -
Manual HVAC
HVAC Mode Door Actuator (w/ A/C) HVAC Recirculating/Fresh Air Actuator
(w/ A/C)
ff=p
B [Bjp^tg H] a
[E)B [G] BB BB JaZ B

V J BE @ B
240182
9 Way 240183
Connector Part
Informatkan 7 Way

Male Connector Part
Circuit Information
Male
Pin Wire Color No. Function Circuit
A LT GRN/BLK 224 Mode Actuator Mod 8 Pin Wire Color No. Function
B BRN/GRN 221 Mode Actuator Mode 5 A-C
Not Used
C BRN/BLK 227 Mode Actuator Mode 2 Recirculate/Fresh

D PPL/YEL 233
Actuator ON
D BRN/BLU 226 Mode Actuator Mode 1
E LTGRN 236 Blower motor
E LT GRN/YEL 225 Mode Actuator Mode 7
F
Not Used
F BRN/ WHT 223 Mode Actuator Mode 3
Recirculate/Fresh
G BRN 222 Mode Actuator Mode 4 G PPL/GRN 234
Actuator OFF
H BRN/YEL 220 Mode Actuator Mode 6 H PPL/ WHT 235 HVAC Controller C2
J BLK 219 Mode Actuator

Functional Check HVAC Blower Controls System Check
The following conditions indicate that the electrical A constant air rush noise is typical of high-speed
circuits are functioning properly: blower operation. Some systems and modes may be
The air conditioning operates at all speeds in noisier than others.
any position except for OFF. Perform the following steps on a similar vehicle in

The compressor clutch engages. order to determine whether the noise is typical or
The system is charged properly if the hand-felt excessive:
temperatures of the following components are 1. Close the doors and the windows of the
the same: vehicle.
The evaporator inlet pipe 2. Sit in the vehicle.

The receiver/dryer or dehydrator surface of an 3. Turn the ignition to the ON position. Do not
opening system start the engine.
The air conditioning control head is operating 4. Set the temperature for maximum cooling.
correctly when the air conditioning control head
5. Run the blower on the 4 speed.
distributes air from the designed outlets.
6. Cycle through all of the blower speeds, the
modes and the temperature settings.
1998 -
MD-lsuzu
Manual 1-79
7. Determine if the noise is one of the following

The noiseis constant at high blower speeds
types of noise: in
certain modes, but can be eliminated at
The noise is constant but decreases with lower blower speeds in other modes.
blower speed reduction. The following noises Typical noises are a flutter or a rumble.
are typical:
8. Complete the following steps if the noise
A whine persists:
A tick/click
Remove the blower assembly.
. A flutter
Inspect for obstructions or foreign material
A scrape that may cause noise.
The noise occurs only at startup or is
Remove any obstructions from the blower
intermittent. assembly.
This noise may occur at cold ambients and If no obstructions are found, replace the
low blower speeds. blower assembly.
Typical noises are a squeal or a screech.
HVAC Compressor Clutch Does Not Engage

1. Locate the vehicle in an
area with ambient air
temperature greater than 10'C (50'F).
2. Start the engine and maintain at 1000 rpms.
3. Place the A/C mode switch in the ON position.
4. Place the fan control switch in position 1.
1 5. With the blower motor operating, place the fan
control in position 4.
6. Place the temperature control lever, on the A/C

mode switch, in the full left COLD position.
7. Ensure the A/C compressor clutch engages during a
Go to System
5 minute observation period and cold air is produced.
Performance
Does the A/C compressor clutch engage? Chart Go to Step 2
1. Place the fan control switch in position 1.
2. Remove the A/C compressor clutch relay from the

relay socket.
2
3. Connect a fused jumper wire between terminal 30

and terminal 87 in the A/C compressor clutch relay

socket.
Does the A/C compressor clutch engage? Go to Step 3 Go to Step 11
1. Connect a self-powered test lamp between

terminal 86 in the compressor relay socket and
3 chassis ground.
2. Set the window washer switch to the ON position.

Connect a test lamp between the A/C compressor relay

4 socket terminal 85 and chassis ground.
Repair the open CKT 211 (GRN/RED) between S 307 and

5 terminal 86 in the compressor relay socket.
1. Install the compressor relay into the relay socket.

6
2. Place the window washer switch in the ON position.

Does the compressor clutch engage? Go to Step 8 Go to Step 9
Locate and repair the open the CKT 210 (LTGRN) wire
in
betweeen terminal 87 in the blower relay and terminal 85
7
in the A/C compressor relay.
1998 -
MD-lsuzu
Manual HVAC
HVAC Compressor Clutch Does Not Engage (cont'd)

1. Disconnect the harness connector from the thermo

switch.
8
2. Connect a fused jumper between terminal A and

terminal B in the thermo switch harness connector.

Replace the compresor relay.

9
1. Make sure the evaporator icing condition does

not exist.
10
2. Replace the thermo switch.

Connect a fused jumper between terminal A in the thermo

11 switch harness connector and chassis ground.
1. Connect a jumper between terminal B in the thermo

switch harness connector and chassis ground.
2. Remove the D201 diode module.

12 self-powered test lamp between
Connect

a
3.
terminal 1 E in the D201 diode module harness
connector and chassis ground.
Locate and repair open in CKT 18/213 (GRN/RED)
13 between S 307 and terminal A in the thermo switch.
1. Disconnect the harness connector C2 from the

A/C mode switch.
2. Connect a jumper between terminal 3 in the

A/C mode switch harness connector C2 and chassis
14 ground.

terminal 1 F in the D201 diode module harness
Locate and repair open in CKT 17/215 (GRN/YEL)
between terminal 1 E in the D201 diode module harness
15 connector and terminal B in the thermo switch harness
connector.
Inspect diode D201.
16
Is diode D201 in good condition? Go to Step 18 Go to Step 19
Locate and repair open in CKT 177/216 (GRN) between

terminal 1 F in the D201 diode module harness connector
17
and terminal 3 in the A/C mode switch harness connector.


Replace the A/C mode switch.
18

Replace the diode module.
19

Connect atest lamp between the A/C compressor clutch
20 relay socket terminal 87 and chassis ground.
1998 -
MD-lsuzu
Manual 1-81
HVAC Compressor Clutch Does Not Engage (cont'd)

Connect self-powered test lamp between the
a
A/C compressor clutch relay socket terminal 87 and

21
chassis ground.
Locate and repair open in CKT 201/207 (GRN/RED)
between circuit breaker 20 and terminal 30 in the
22 A/C compressor relay socket.


Replace the compressor clutch relay.
23
1. Disconnect harness connector from the A/C pressure

cut-off switch.

24 terminal 87 in the A/C compressor relay socket and
terminal 3 in the A/C refrigerant pressure switch

connector.
Connect a self-powered test lamp between terminal 4 in
the A/C refrigerant pressure switch harness connector and
25
chassis ground.
Locate and repair the open in CKT 203/208 between

terminal 87 in the A/C compressor relay and terminal 3 in
26 the A/C refrigerant pressure switch.

1. Charge the A/C system with freon. Refer to

Refrigerant Recovery and Recharging.
27
2. Replace the A/C pressure cutoff switch.

Is the replacement complete? System OK Go to Step 28
1. Disconnect the harness connector from the

A/C compressor clutch.
28 2. Connect a self-powered test lamp between the

A/C compressor clutch terminal and chassis ground.

Locate and repair open CKT 6/59 (DK GRN) between

in
terminal 4 in the A/C refrigerant pressure switch harness
29 connector and the A/C compressor clutch harness
connector terminal.
Repair or replace the A/C compressor clutch.

30
1998 -
MD-lsuzu
Manual HVAC
HVAC Compressor Clutch Does Not Disengage

Verify the symptom.
1 Does the A/C compressor clutch remain continuously
engaged with the A/C switch in the OFF position? Go to Step 2
1. Disconnect the A/C compressor clutch harness

connector from the A/C compressor.
2. Place the A/C on/off switch on the A/C mode switch
to the OFF position.
2
3. Place the fan control switch in the OFF position.

4. Start the engine and maintain at approximately
1000 rpms.
Does the A/C compressor clutch disengage? Go to Step 4 Go to Step 5
1. Turn the engine OFF.
3. Remove the harness connector from the A/C pressure
cutoff switch.
4
4. Connect a self-powered test lamp between terminal 4

in the A/C pressure cutoff switch harness connector
and chassis.
Replace the A/C compressor clutch.
5

Locate and repair short to B positive in CKT 59 (DK GRN)
between terminal 4 in the A/C pressure cutoff switch
6 harness connector and the A/C compressor clutch harness
connector.
Repair or replace the A/C pressure cutoff switch.
7
Blower Motor Inoperative at Any Speed

2. Place the blower speed switch in the HI position.

1
3. Connect a test lamp between blower relay

terminal 30 and the chassis ground.

Locate and repair the open in CKT 190 (RED) wire
2 between the I/P fuse block and the blower relay.

Connect a test lamp between blower relay terminal 85 and
3 the chassis ground.

Locate and repair the open in CKT 198 (BRN) wire
4 between the I/P fuse block and the blower relay.
1998 -
MD-lsuzu
Manual 1-83
Blower Motor Inoperative at Any Speed (cont'd)

Connect a test lamp across blower motor terminal A and
5 the chassis ground.

Locate and repair the open in CKT 191 (GRN) wire
6 between the blower motor and the blower relay.

Connect a self-powered test lamp across blower motor
7 terminal B and ground.

Replace the blower motor.
8

Connect a self-powered test lamp across A/C mode switch
9 connector C3 terminal 5 and the chassis ground.

Locate and repair the open circuit between the blower
10 motor and A/C mode switch.

Connect a self-powered test lamp between A/C mode
11 switch connector C3 terminal 1 and ground.

12
Locate and repair the open CKT 179 (BLK) wire

in
13 between A/C mode switch connector C3 and ground.
Blower Motor Low Speed Inoperative

1 position.
Is LOW speed the failing speed? Go to Step 2 Go to Step 3


resistor.

3. Place the blower speed switch in the failing speed
position.


.
LOW-1
MED LOW-4
.
MED-HI-6
1998 -
MD-lsuzu
Manual HVAC
Blower Motor Low Speed Inoperative (cont'd)

4
Disconnect the A/C mode switch connector C 3 terminal 2

5 and chassis ground.

6 resistor and the A/C mode switch.

7
Blower Motor Medium Speed Inoperative

Place the blower speed switch in the failing speed position.
1
Is MED speed the failing speed? Go to Step 2 Go to Step 3

Locate and repair the open CKT 192 (BLU/RED)
in

1. Disconnect the connector at the blower motor resistor.
position.

blower motor resistor connector terminal for the
3

. LOW-1
. MED LOW-4
. MED-HI-6

4



7
1998 -
MD-lsuzu
Manual 1-85
Blower Motor Low and Medium Speeds Inoperative

2. Place the temperature selector in the LOW blower
speed.
1 3. Disconnect the connector at the blower motor resistor.

blower motor resistor connector terminal 1 for the
CKT 196 (BLU/WHT) wire and the chassis ground.
2

Connect a self-powered test lamp between the A/C mode
3 switch connector C3 terminal 2 and the chassis ground.

Locate and repair the open in CKT 180/196 (BLU/WHT)
wire between the A/C mode switch and the blower motor
4
resistor.
Does the test lamp light? Ststem OK Go to Step 5

5
Blower Motor High Speed Inoperative

Place the blower speed switch in the failing speed position.
1
Is HIGH speed the failing speed? Go to Step 2 Go to Step 3

Locate and repair the open CKT 192 (BLU/RED)
in
1. Disconnect the connector at the blower motor resistor.

position.

blower motor resistor connector terminal for the
3

.
LOW-1
. MED LOW-4
.
MED-HI-6

4


7
1998 -
MD-lsuzu
Manual HVAC
Condenser Fan Inoperative

1. Backprobe relay center 2 with a test lamp from
blower relay terminal 85 to ground.
1
2. Place ignition switch in RUN.

Did the test lamp light? Go to Step Go to Step
Locate and repair open CKT196, CKT337, or CKT371

2 (BRN) between IP fuse block and relay center 2.
Backprobe relay center 2 with a test lamp from blower

3 relay terminal 30 to ground.

Locate and repair open CKT190 (LT GRN) between IP
4 fuse block and relay center 2.

5 relay terminal 86 to B+.

Locate and repair open CKT199 (BLK) between relay
6 center 2 and G105.

7 relay terminal 87 to ground.

Replace the blower relay.
8

Backprobe relay center 2 with a test lamp from A/C
9 condenser fan relay terminal 85 to ground.

Locate and repair open in CKT204 (LT GRN) between
10 blower relay and A/C condenser fan relay.

11 condenser fan relay terminal 30 to ground.

Locate and repair open CKT201 (GRN/RED) between I/P
12 fuse block and relay center 2.

13 condenser fan relay terminal 86 to B+.

Backprobe control assembly with a test lamp from
14 connector C2 terminal 3 to B+.

Replace the control assembly. Refer to, Control Assembly
15 Replacement.
Backprobe A/C temperature sensor with a test lamp from

16 connector C2 terminal 3to B+.
1998 -
MD-lsuzu
Manual 1-87
Condenser Fan Inoperative (cont'd)

Locate and repair open CKT603, CKT206, CKT216 or
CKT177 (GRN) between A/C temperature sensor and
17
control assembly.
Backprobe A/C temperature sensor with a test lamp from
18 cavity 2C2 2 to B+.
Replace the A/C temperature sensor.

19 Refer to A/C Temperature Sensor Replacement

20 condenser fan relay cavity 87 to ground.

Replace the A/C condenser fan relay.
21
Backprobe A/C condenser fan motor with a test lamp from

22 cavity 6 to ground.

Locate and repair open CKT202, CKT206 and 1727
(DK BLU/WHT) between relay center 2 and A/C condenser
23
fan motor.
Backprobe A/C condenser fan motor with a test lamp from
24 cavity 5 to B+.
Replace the A/C condenser fan motor.

25

Locate and repair open CKT150 (BLK) between A/C
26 condenser fan motor and G107.
Condenser Fan On at All Times

Place ignition switch in run.

1 Remove A/C condenser fan relay.
Does the A/C condenser fan turn off? Go to Step Go to Step
Replace the A/C condenser fan relay.

2
Is the repair complete? , System OK

Locate and repair short to voltage in CKT202, CKT1727
(DK BLU/WHT) between relay center 2 and A/C condenser
3
fan motor.
Is repair complete? System OK
1998 -
MD-lsuzu
Manual HVAC
System Performance Chart 7. Connect the low pressure hose (1).

Tools Required 8. Connect the high pressure hose (2).
J 39500
1. Park the vehicle inside a building or in a
10. Stabilize the engine to a normal idling condition.
shaded area. 11. Press the button in the ON position.
2. Place the transmission in PARK or NEUTRAL. 12. Press the MAX/REC/RC button in the ON
3. Open the hood. position.
4. Secure the hood. 13. Adjust the blower speed to HI.
5. Remove the low pressure hose cap. 14. Adjust the temperature control to full COLD.
6. Remove the high pressure hose cap. 15. Carefully follow the manufacturer's instructions.
The normal temperature guideline for pressures
readings is approximately 2530 "C (7786 F).
The normal pressure guideline at ambient for the low
pressure side is approximately 127265 kPA
(18.5-38.4psi).
The normal pressure guideline at ambient for the
high pressure side is approximately 1,3731,765
kPA (199255.9 psi).
1204209495288659
229676
System Performance Chart

Pressure Temperature
(kPa) (psi) (C) (F)
36 5.3 -20 -4.4
67 9.7 -15 5
104 15 -10 14
147 21 -5 23
196 28 0 32
255 37 5 41
314 45 10 50
392 57 15 59
1998 -
MD-ISUZU
Manual 1-89
System Performance Chart (cont'd)

Pressure Temperature
471 68 20 68
569 82 25 77
677 98 30 86
785 114 35 95
912 132 40 104
1059 154 45 113
1216 176 50 122
Refrigerant System Checks

High Pressure Abnormally Low
Problem Action
The system contains insufficient Check the refrigerant system for leaks. Refer to Leak Testing.
refrigerant.
The expansion valve is clogged or Replace the expansion valve. Refer to Thermal Expansion Valve Replacement.
defective, with a low pressure
indicating vacuum.
Frost or dew exists on the refrigerant Replace the receiver/dryer or dehydrator. Refer to Receiver Dehydrator
line before and after the Replacement.
receiver/dryer or the dehydrator or the
expansion valve and low pressure
indicate vacuum. This may be due to
restriction caused by debris or
moisture in the receiver/dryer or
dehydrator.
The high and low pressure balanced Replace the compressor. Refer to Compressor Replacement.
quickly with the engine shut off. This
may be caused by a defective
compressor seal or poor compressor
operation.
Low Pressure is Abnormally High

Problem Action
The low pressure drops after the 1. Discharge the refrigerant.
condenser is cooled by water. This 2. Recover the refrigerant.
may be caused by excessive
refrigerant in the system. 3. Recharge the refrigerant.
Refer to Refrigerant Recovery and Recharging.
The low pressure hose temperature Replace the expansion valve. Refer to Thermal Expansion Valve Replacement.
around the compressor refrigerant line
connector is lower than around the
evaporator. This may be caused by
improper expansion valve operation.
The high or low pressure balanced Replace the compressor. Refer to Compressor Replacement.
quickly with the engine off. This may
be caused by improper compressor
operation.
1998 -
MD-lsuzu
Manual HVAC
Low Pressure is Abnormally Low

Problem Action
The system contains insufficient Check the refrigerant system for leaks. Refer to Leak Testing.
refrigerant.
Frost on the expansion valve. This Replace the expansion valve. Refer to Thermal Expansion Valve Replacement.
may be caused by a plugged
expansion valve.
A distinct temperature difference Replace the receiver/dryer or dehydrator. Refer to Receiver Dehydrator
exists between the receiver/dryer or Replacement.
the dehydrator inlet and the outlet
refrigerant lines. This may be caused
by a clogged receiver/dryer or
dehydrator.
The low pressure indicates that the Replace the expansion valve. Refer to Thermal Expansion Valve Replacement.
vacuum and the expansion valve
outlet refrigerant line is not cold. This
may indicate that the expansion valve
temperature sensor is defective.
The low pressure reading decreases Replace the refrigerant line.
or shows a vacuum. This may be
caused by a clogged or blocked
refrigerant line.
The evaporator core is frozen. This Replace the A/C Temperature Sensor. Refer to A/C Temperature Sensor in
may be caused by a defective A/C Heater/Vent Module Replacement.
Temperature Sensor.
Low and High Pressures are Abnormally High

Problem Action
DEFINITION: The low and high pressure readings are abnormally high.
The system contains excessive 1. Discharge the refrigerant.
refrigerant.
2. Recover the refrigerant.
3. Recharge the refrigerant. Refer to Refrigerant Recovery and Recharging.
The condenser is clogged or dirty. Clean the condenser fins.
The system contains excessive air. 1. Discharge the refrigerant.
This is indicated if the suction (low
pressure) hose is not cold.
Low and High Pressures are Abnormally Low

Problem Action
The system contains excessive 1. Discharge the refrigerant.
refrigerant.
Leak Testing Caution: Take care to prevent personal injury

which could occur due to touching a hot engine
Caution: Avoid breathing A/C Refrigerant 134a when testing. Tests should be done with the
(R-134a) and lubricant vapor or mist. Exposure
engine "Off and as cool as possible. Do not
may Irritate eyes, nose, and throat. To remove operate the detector in a combustible atmosphere
R-134a from the A/C system, use service
since Its sensor operates at high temperature.
equipment certified to meet the requirements of
SAE J2210 (R-134a recycling equipment). If Perform a refrigerant leak test on the system when
accidental discharge occurs, ventilate work area the following conditions exist:
before resuming service. Additional health and A leak is suspected.
safety information may be obtained from A service operation disturbs the components,
refrigerant and lubricant manufacturers. lines or connections.
1998 -
MD-lsuzu
Manual 1-91
Electronic Leak Detector

Tools Required
J 39400 Electronic Leak Detector
The J 39400 is a small unit which operates on
12V DC.
The detector provides an audible signal. The signal
increases in frequency as R-134a is detected.
Use the included instructions in order to ensure that
the instrument is properly calibrated. Ensure that the
detector is used in the proper setting for the type of
refrigerant being tested.
Place the detector GAS switch in the R-134a setting
prior to use.
J39400
82106
When using the electronic leak detector, ensure that

the following conditions exist:
Each joint is completely circled.

The scan rate is 25-51 mm (1.2 in) per second.
The tip of the probe is as close to the surface as
possible but no more than 6 mm (0.25 in) away.
The air intake is not blocked.
Important: Halogen leak detectors are sensitive to

the following compounds:
1. Windshield washing solutions
2. Solvents and cleaners
82101 3. Adhesives
In order to prevent a false warning, ensure that all of
Inspect the refrigerant fittings and the connections for
the surfaces are clean. Ensure that all of the
leaks. The following conditions may cause leaks:
surfaces are dry. The ingestion of liquids will damage

Improper torque the detector.

Damaged 0-ring seals A leak is indicated when the audible tone changes
Lack of lubricant on the 0-ring seals from a steady 1-2 clicks per second to a solid alarm.
Dirt or debris across the 0-ring seals Adjust the balance knob frequently in order to
maintain the 1-2 clicks per second rate.
Small pieces of lint from cotton gloves or shop
cloths Important: Always follow the refrigerant system around
in a continuous path so that no areas of potential
leaks are missed. Always test all of the following areas
in order to ensure that the entire system is leak free,
even when one leak is already found.
Use this procedure in order to test the following areas:
The A/C evaporator inlet and outlet
The A/C accumulator inlet and outlet
The A/C condenser inlet and outlet
All brazed and welding areas
All areas that exhibit signs of damage
The hose couplings

The A/C compressor rear head

The housing joints
1998 -
MD-lsuzu
Manual HVAC
Service Ports/Access Valves 6. Listen to the detector. If the detector sounds a

is the primary seal for the service
solid alarm, a leak has been found.
The sealing gap
ports. This cap contains a specially designed 0-ring 7. Visually inspect the core face with a flashlight
seal or gasket which provides a leak-free seal. for evidence of refrigerant oil.
The following conditions will result in the loss of
A/C Compressor Block Fitting and Shaft Seal
refrigerant charge:
1. Blow shop air behind and in front of the A/C
A loose cap
compressor armature/pulley for 15 seconds

A missing cap or more.

The use of a wrong cap 2. Wait for 12 minutes.
A/C Evaporator Core 3. Probe the area in front of the pulley.
Leaks in the A/C evaporator core may be difficult to 4. Listen to the detector. If the detector sounds a
solid alarm, a leak has been found.
detect. Use the following procedure in order to test
the core:
Leak Inspection
1. Turn the blower fan on HIGH for 15 or more Before disassembling any A/C compressor
seconds. components, inspect for leaks. Replace the
2. Turn off the blower fan. A/C compressor if a leak is found in any of the
following areas:
3. Wait for 10 minutes.
4. Remove the blower mower resistor. Refer to

The valve plate
Blower Motor Resistor Replacement. The oil plug
5. Insert the leak detector probe. Be sure to insert
the leak detector as close to the A/C
evaporator as possible.
Heating Insufficient
Poor Defrosting
Problem Action
1. The door(s) which control 1. Determine and correct the cause of the malfunction.
airflow are not functioning
2. Determine and correct the cause of the malfunction. Refer to Blower Motor
correctly. Inoperative at Any Speed.
2. The blower motor is not 3. Remove the blockage.
working.
4. Flush the cooling system. Refer to Flushing.
3. There is blockage in the
5. Determine and correct the cause of the malfunction. Refer to Thermostat
defroster outlets.
Diagnosis.
4. A restricted heater core and/or
hoses. 6. Clean the air conditioning filter. Refer to Passenger Compartment Air Filter
Replacement.
5. A faulty thermostat and/or
radiator cap. 7. Remove the blockage.
6. There is blockage in front of the

7. There is blockage in the path of

the door.
1998 -
MD-lsuzu
Manual 1-93
No Heat (Blower Motor Working)

Problem Action
1. There is low engine coolant 1. Check the engine coolant level. Refer to Draining and Filling Cooling System
level. (Cooling System).
2. A faulty thermostat and/or 2. Determine and correct the cause of the malfunction. Refer to Thermostat
radiator cap. Replacement.
3. A restricted heater core and/or 3. Flush the cooling system. Refer to Flushing.
hoses.
4. Check the actuator function and replace as necessary.
4. A faulty actuator. 5. Seat the pivot shaft of the door(s) correctly.
5. The pivot shaft of door(s) is not 6. Clean the air conditioning filter. Refer to Passenger Compartnvent Air Filter
seated correctly. Replacement.
6. There is blockage in front of the 7. Remove the blockage.
7. There is blockage in the path of

the door.
Heater Gurgling Sound

Problem Action
1. There is low engine coolant. 1. Check the engine coolant level. Refer to Draining and Filling Cooling System
A restricted heater core and/or (Cooling System).
2.
hoses. 2. Flush the cooling system. Refer to Flushing.
Poor Ventilation
Problem Action
1. A blockage in the heater 1. Remove the blockage in the heater module.
module.
2. Remove the blockage in the recirculating/fresh air duct.
2. A blockage in the 3. Remove the blockage, repair and replace as necessary.
recirculating/fresh air duct.
4. Repair and replace the door as necessary.
3. A binding or sticking of the
recirculating/fresh air door. 5. Seat the pivot shaft of the door.
6. Seat the pivot shaft of the door(s).
4. The recirculating/fresh air door
is not operating.
5. A faulty recirculating/fresh air

actuator.
6. The pivot shaft of the door is

not seated correctly.
Heat Excessive
Problem Action
1. The temperature door and/or 1. Determine and correct the cause of the malfunction.
actuator are faulty. Determine and correct the cause of the malfunction. Refer to Engine
2.
2. The engine is overheating. Overheating.
________________________
Cooling Insufficient - A/C Inoperative
High Pressure is Abnormally High
Problem Action
The A/C condenser is clogged or dirty. Clean the A/C condensor fins.
The cooling fan is not operating Check system for malfunction.
properly.
1998 -
MD-lsuzu
Manual HVAC
A/C Component Checks

Problem Action
The A/C compressor belt is loose or Adjust or replace the drive belt.
broken. Refer to Engine Mechanical,
The armature friction face is glazed. Clean or replace the magnetic armature face.
The clearance between the magnetic Adjust the clearance.
drive plate and the pulley is incorrect. Refer to Compressor Magnetic Clutch (Disassembly).
The A/C compressor is seized. Replace the A/C compressor. Refer to Compressor Replacement.
The refrigerant is insufficiently 1. Discharge the refrigerant. Refer to Refrigerant Recovery and Recharging.
charged or excessively charged.
2. Recover the refrigerant. Refer to Refrigerant Recovery and Recharging.
3. Recharge the refrigerant.
Refer to Refrigerant Recovery and Recharging.
Leaks are present in the refrigerant Inspect the refrigerant system for leaks.
system. Refer to Leak Testing.
The A/C condenser is clogged. The Clean or replace the A/C condenser, as necessary.
radiation in the A/C condenser is not Refer to Condenser Replacement.
sufficient.
The A/C expansion valve is operating Replace the A/C expansion valve.
incorrectly due to a foreign substance.
Refer to Thermal Expansion Valve Replacement.
Air Delivery Improper Under certain climate and operating conditions, a

musty odor develops from mold growth in the
Musty Smell of Coolant Smell
evaporator core face. This odor is generally

Check for water leaks. Seal the body as temporary. As climate conditions change, the
necessary. condition will repair on its own. However, if the odor
Check the evaporator drain for blockage. persists, remove the evaporator core and clean the
Remove blockage. face with an appropriate cleaner.
Check the coolant level. If it is low inspect the Odors may be emitted from the air conditioning
heater core or heater pipes/hoses. system primarily at startup in hot, humid climates.
This odor may be the result of debris in the
heater/A/C evaporator case or growth of mold on the
Evaporator core.
Repair Instructions
Odor Correction
Musty Smell
Problem Action
Water Leaks (Body) Seal the body.
Evaporator Drain Clean the drain.
Mold/Mildew Clean the evaporator.
Coolant Smell
Problem Action
Anti-freeze
Heater core

Heater pipe/hoses
Refrigerant Leak
Problem Action
Refrigerant Oil Evaporator Core
1998 -
MD-lsuzu
Manual 1-95
Under certain climate and operating conditions, a 9. Turn the ignition to the ON position. Do not
musty odor develops from mold growth in the start the vehicle.
evaporator core face. This odor is generally 10. Set the mode selector to Max/Rec/Rc.
temporary. As climate conditions change, the
condition will repair on its own. However, if the odor 11. Set the blower speed to 1.
persists, remove the evaporator core and clean the 12. Set the temperature to full COLD.
face with an appropriate cleaner. 13. Open all of the windows and the doors.
If diagnosis indicates that a component of the A/C
14. Exit the vehicle.
systems needs to be cleaned, use the following 15. Place a drain pan with at least a 2-quart capacity
procedure: below the heater/A/C evaporator drain hole.
Cleaning Procedure Position the drain pan so that it will collect the
disinfectant and the rinse water runoff.
Tools Required
If necessary, install an additional hose onto
J 36645 Evaporator Cleaning Gun

the drain so that all of the fluid goes into the

Disinfectant Kit
drain pan.
Caution: Procedure should only be performed on 16. Turn the pedestal fan to 4 in order to provide
a cold vehicle to prevent the disinfectant from cross ventilation during the cleaning procedure.
coming in contact with hot engine components.
Disinfectant can cause substantial but temporary Important: Do not allow disinfectant to come
into contact with hot engine components such
eye Injury. Do not get In eyes or clothing. Wash
thoroughly with soap and water after handling. as the exhaust manifold.
17. Insert the nozzle of the J 36645
Important: Complete the following steps if
disinfectant gets into your eyes: 18. Spray the disinfectant directly toward the A/C
evaporator face.
1. Hold your eyelids open

Saturate the core completely.
2. Flush your eyes with a steady, gentle stream of
water for 15 minutes.

Use the entire container of solution.
Be sure to cover the corners and the edges.
3. Obtain medical attention if the irritation persists.

Put on rubber gloves and safety goggles. 19. Turn the ignition to the OFF position.
1.
20. Allow the core to soak for 5 minutes.
2. Pour the small bottle of the two-part Air
Conditioning System Disinfectant Kit into the 21. Inspect underneath the vehicle.
large bottle. Verify that the drain is operating properly. If
3. Seal the container. necessary, use a razor blade or sharp knife in

order to unclog and increase the drain plug slits.
4. Invert the large container 1-2 times in order to
mix the contents. 22. Turn the ignition to the ON position. Do not
start the vehicle.
5. Inspect underneath the vehicle in order to verify
that the drain outlet is not plugged. 23. Use the spray gun in order to thoroughly rinse
the A/C evaporator core with clean water.
6. Connect the battery charger in order to avoid
draining the battery during the cleaning Be sure to remove all of the disinfectant residue.
procedure. Use at least 1-2 liters of rinse water.
Notice: Do not allow the metal coils of the 24. Turn the ignition to the OFF position.
blower resistor to become grounded to any 25. Reinstall the blower resistor. Refer to Blower
metal surface as this may result in internal Motor Resistor Replacement.
circuitry damage.
26. Discard the disinfectant and the rinse water that
7. Remove the blower resistor. Be sure to leave was collected in the drained pan. Be sure to
the wiring connectors attached. Refer to Blower discard the liquid in an approved manner.
Motor Resistor Replacement.
Refrigerant Recovery and Recharging
8. Inspect the heater/A/C evaporator case for debris.
Remove any debris that is present through

The air conditioning refrigerant (R-134a) recovery,
recycling and recharging system (J 39500-A)
the blower resistor opening.
completes the following actions with one hookup:
If the debris is imbedded into the A/C
evaporator core face and cannot be

Removes Refrigerant-134a from the vehicle
A/C system
removed, remove and clean the core.
If large amount of debris is present in the
a

Recycles
heater/A/C evaporator case, seal the air inlet
Recharges
screen around the air intake in the cowl area.
1998 -
MD-lsuzu
Manual HVAC
The following actions ensure a constant supply of Do not attempt to use one set of equipment for both
clean/dry refrigerant for A/C system charging: R-12 and R-134a, as all equipment contains residual

Single-pass filtering during the recovery cycle amounts of refrigerant and/or lubricant. This would
contaminate and damage the recover/recycle

Automatic multiple-pass filtering during the
equipment.
evacuation cycle
Do not use adapters in order to convert one size
Important: R-12 and R-134a require separate and fitting to the other. Refrigerant/lubricant contamination
non-interchangeable sets of recovery, recycle and
will occur and system failure may result.
recharge equipment. The refrigerants and lubricants
are not compatible and cannot be mixed.
Compressor Replacement
Removal Procedure
1. Tilt the cab. Refer to Cab Tilting in General
Information.
Caution: Refer to Battery Disconnect Caution
in Cautions and Notices.
2. Disconnect the negative battery cables. Refer to
3. Discharge and recover the refrigerant from the
system. Refer to Refrigerant Recovery and
Recharging.
4. Remove the drive belt. Refer to Engine
Mechanical.
5. Remove the electrical connector from the
A/C compressor, as necessary.
6. Remove the A/C compressor block fitting bolt.
230251
Important: When removing sealing washers, keep

dirt and foreign material from getting on the following
sealing surfaces:

The washers
The block fitting
The A/C compressor ports
Clean all of the sealing surfaces with a lint-free rag.
7. Remove the A/C compressor sealing washers.

Discard the A/C compressor sealing washers.
8. Remove the refrigerant hoses.
334243
1998 -
MD-lsuzu
Manual 1-97
9. Remove the idler pulley adjusting bolt.
230259
10. Remove the bolts from the mounting bracket.
1. Fill the A/C compressor. Refer to Refrigerant Oil
Distribution Specifications.
2. Position the A/C compressor on the mounting

bracket.
230255
1998 -
MD-ISUZU
1-98 HVAC Systems with A/C
Manual HVAC
3. Install the bolts on the mounting bracket. Do

not tighten at this time.
230259
Important: When installing the sealing washers,

keep dirt and foreign material from getting on the
following sealing surfaces:
The washers
. The block fining

Do not reuse the sealing washers.

Do not oil the sealing washers prior to assembly.
4. Install new sealing washers onto the pilots of

the block fitting. Ensure that the washers
bottom against the surface of the block fitting.
334249
5. Install the refrigerant hoses on the A/C

compressor hose block fitting bolt.
Notice: Refer to Fastener Notice in Cautions
and Notices.
6. Hold the block in place. Hand tighten the

A/C compressor hose block fitting bolt.
Tighten
Tighten the A/C compressor hose block fitting
bolt to 35 N.m (26 Ib ft).
7. Install the A/C electrical connector to the

A/C compressor.
8. Install the drive belt and idler pulley
adjusting bolt.
Tighten
Tighten the mounting bracket bolts to 39 N.m
(29 Ib ft).
230251 9. Install the electrical connector to the
A/C compressor.
1998 -
MD-lsuzu
Manual 1-99
10. Install the drive belt and the idler pulley

adjusting bolt.
Tighten
Tighten the mounting bracket bolts to 39 N.m
(29 Ib ft).
11. Install the negative battery cables.
12. Install the refrigerant to the system. Refer to
13. Inspect the system for leaks. Refer to Leak
Testing.
14. Lower the cab.
Compressor Sealing Washers Replacement

Removal Procedure
Information.
2. Remove the negative battery cables. Refer to


Recharging.
Important: When removing the sealing

washers, prevent dirt and foreign material from
getting on the sealing surfaces of the washers,
block fitting or A/C compressor ports. Clean all
of the sealing surfaces with a lint-free cloth.
4. Remove the compressor hose block fitting bolt

from the A/C compressor. 230251
5. Remove the sealing washers.

334243
7998 -
MD-lsuzu
Manual HVAC
6. Remove the A/C compressor hoses.
334249
prevent dirt and foreign material from getting on the
sealing surfaces of the washers, block fitting or A/C
compressor ports. Clean all of the sealing surfaces
with a lint-free cloth.
1. Install new sealing washers onto the pilots of
the block fitting. Ensure that the washers
334249
2. Install the A/C compressor hoses onto the

A/C compressor. Secure the hoses with the
A/C compressor hose block fitting washer and
the bolt.
and Notices.
3. Hold the block in place. Hand tighten the
A/C compressor block fitting bolt.
Tighten
4. Connect the negative battery cables.

5. Add refrigerant to the system. Refer to
Testing.
7. Lower the cab.

230251
7998 -
MD-lsuzu
Manual 1-101
0-Ring Replacement

Before attempting any service that will expose
the refrigerant lines or the components to the
atmosphere, refer to Handling Refrigerant
R-134a., Handling of Refrigerant Lines and
Fittings and Maintaining Chemical Stability.

Follow the instructions in Refrigerant Recovery
for the unit that is being serviced.
Install new replacement air conditioning 0-ring
seals whenever a joint or a fitting is installed. If
the 0-ring seals are included with new
replacement components, use these included
0-ring seals. Excessive leakage of
Refrigerant-134a may occur if the service
replacement 0-ring seals do not bear the
specified part numbers. Refer to the part
number for identification.

Coat the air conditioning 0-ring seals with
525 viscosity refrigerant oil just before
installation. Slip the air conditioning 0-ring seals
onto the flange tube in order to ensure proper
locating and sealing. Do not soak the 0-ring
seals in refrigerant oil. Soaking the 0-rings may
cause swelling and reduced sealing
effectiveness.

Examine the 0-ring seals and the fitting before
installation. Ensure that the parts are not nicked
or deformed. Replace nicked or deformed parts
in order to prevent leakage.
Compressor Magnetic Clutch

J33939
(Disassembly)
Tools Required
J 33939 Armature Holder
J 33944-A Armature Plate Remover
J 33944-4 Puller Forcing Screw
1. Remove the armature bolt from the

A/C compressor shaft by inserting the two
pins of the J 33939 into any two threaded
holes of the armature.
2. Remove the armature. Replace the driver plate

and pulley if the surface shows signs of
damage due to excessive heat.
230267
1998 -
MD-ISUZU
02 HVAC Systems with A/C -
Manual HVAC
3. Remove the shim(s) from the front housing.
Compressor Magnetic Clutch (Assembly)

Tools Required
. J 33940-A Puller Installer
. J 8092 Driver Handle
J 4245 External Snap Ring Pliers
1. Install the shim on the A/C compressor shaft.
2. Clean the armature with suitable cleaning solvent.
3. Install the armature onto the A/C compressor
shaft by inserting the two pins of the J 33939
into any two threaded holes of the armature.
4. Use the J 37872 in order to hold the plate.

and Notices
5. Install the armature bolt on the A/C compressor
shaft.
230273
Tighten
Tighten the armature bolt to 13 N.m (113 Ib in).
6. Inspect the armature clearance. Ensure that the

armature clearance is between 0.3 0.6 mm
-
(0.01-0.02 in).
230284
1998 -
MD-ISUZU
Manual 1-103
Compressor Magnetic Clutch (Pulley)

Removal Procedure
Tools Required
. J 33943-A Pulley Puller Pilot
J 8433 Compressor Pulley Puller
1. Remove the armature from the A/C compressor.

Refer to Compressor Magnetic Clutch
(Disassembly).
2. Use the J 4245 in order to remove the front

housing snap ring.
3. Remove the front housing snap ring cover, if

equipped.
230287
4. Remove the pulley.

4.1. Align the J 33943-A to the center bolt of
the A/C compressor shaft.
4.2. Turn the puller center bolt to the right
until the pulley is free.
230299
Tools Required
. J 33940-A Puller Installer
. J 8092 Driver Handle
1. Install the front housing snap ring cover, if

equipped.
230309
1998 -
MD-lsuzu
-104 HVAC Systems with A/C -
Manual HVAC
2. Install the front housing snap ring with the

J 4245 External Snap Ring Pliers.
3. Install the pulley.

3.1. Place the J 33940-A on the A/C
compressor shaft.
3.2. Place the J 8092 on the A/C compressor
shaft.
3.3. Tap the end of the J 8092 in order to

guide the rotor pulley on the A/C
compressor shaft until it bottoms out
against the A/C compressor front housing
hub. A distinct change of sound will
indicate that the pulley has bottomed out.
4. Install the armature on the A/C compressor. Refer
to Compressor Magnetic Clutch (Assembly).
Compressor Magnetic Clutch (Field Coil)

Removal Procedure
(Disassembly).
2. Remove the pulley from the A/C compressor.
Refer to Compressor Magnetic Clutch (Pulley).
3. Remove the field coil lead wire from the clip on
top of the A/C compressor front housing.
4. Remove the field coil screw and field coil from
the A/C compressor.
230317
1998
MD-ISUZU
Manual 1-105
1. Install the field coil on the A/C compressor with
the field coil screw.
and Notices.
2. Install the field coil lead wire on the clip on top
of the A/C compressor front housing.
Tighten
Tighten the field coil screw to 5 N.m(44 Ib in).
3. Install the pulley on the A/C compressor.
4. Install the armature on the A/C compressor.

(Assembly).
230319
Compressor Magnetic Clutch

(A/C Compressor Seal)
Removal Procedure
Tools Required
J 33942-B Seal Seat Remover/Installer

(Disassembly).
2. Remove the pulley from the A/C compressor.
Refer to Compressor Magnetic Clutch (Pulley).
3. Remove the field coil from the A/C compressor.
Refer to Compressor Magnetic Clutch (Field Coil).
4. Remove the felt from the compressor shaft, if
equipped.
5. Use the J 33942-B in order to remove the seal
shaft cover (if equipped) from the compressor 230337
shaft.
6. Engage the hook with the shaft seal cover grove.
7. Remove the shaft seal cover off the compressor
shaft.
8. Use the J 4245 in order to remove the snap
ring from the compressor shaft.
9. Use the J 33942-B in order to remove the shaft
seal from the compressor shaft.
10. Engage the hook with the shaft seal grove and
slowly remove the shaft seal off the compressor
shaft.
11. Discard the shaft seal.
1998 -
MD-lsuzu
Manual HVAC
Tools Required
J 34614 Shaft Seal Protector
J 33942-B Seal Seat Remover/Installer
Important: Keep the new shaft seal free from

oil, grease and all contaminates.
1. Clean the shaft seal sealing portions of the

compressor housing and the compressor shaft.
2. Coat the new shaft seal and the J 34614 Shaft
Seal Protector with new compressor oil.
3. Position the J 34614 Shaft Seal Protector over
the compressor shaft.
4. Position the new shaft seal on the compressor

shaft.
230356
1998 -
MO-ISUZU
Manual 1-107
5. Use the J 33942-B in order to install the new

shaft seal on the compressor shaft.
6. Use the J 33942-B in order to install the shaft

seal cover on the compressor shaft.
7. Install the field coil.
8. Install the pulley on the A/C compressor.
9. Install the armature on the A/C compressor.
(Assembly).
230355
1998 -
MD-ISUZU
Manual HVAC
Compressor Overhaul
The operations described here are based on bench
repair with the A/C compressor removed from the
vehicle.
Compressor Hose Assembly Replacement

Removal Procedure
Information.

In Cautions and Notices.


Recharging.
Important: When removing the sealing

washers, prevent dirt or foreign materials from
getting on the surfaces of the following
components:
The washers
229691
The block fitting

Clean all of the sealing surfaces with a
lint-free rag.
4. Remove the A/C compressor hose block

fitting bolt.

334243
1998 -
MD-lsuzu
Manual 1-109
6. Remove the refrigerant hoses from the

A/C compressor.
229709
7. Remove the refrigerant hose from the

A/C condenser.
8. Remove the 0-ring seal.
Discard the 0-ring seal.
229705

A/C evaporator.
11. Remove the following components from the
frame rail and the refrigerant hoses:
The hose clamp nuts
The washers
The bolts
The hose clamps
1998 -
MD-lsuzu
Manual HVAC
Notices.
1. Install the hose clamps to the refrigerant hoses

and frame rail. Secure the hose clamps with
bolts washers and nuts.
Tighten
Tighten the refrigerant hose clamp nuts to
30 N.m (22 Ib ft).
2. Coat the new 0-ring seal with R-134a Swash
Plate P/N AIPDN 2-90188-300-0 refrigerant oil.
3. Install the new 0-ring seal into the A/C
evaporator end of the refrigerant hose.
229709
4. Connect the refrigerant hose to the A/C

evaporator.
Tighten
Tighten the refrigerant hose fitting at the A/C
evaporator to 32 N.m (24 Ib ft).
229714
6. Install the new 0-ring seal in the A/C condenser

end of the refrigerant.

condenser.
Tighten
Tighten the refrigerant hose fitting at the
A/C condenser to 23 N.m (17 Ib ft).
8. Fill the refrigerant hoses. Refer to Refrigerant
Oil Distribution Specifications.
229705
1998 -
MD-ISUZU
Manual 1-111

prevent dirt or foreign materials from getting on the
surfaces of the following components:

The washers

The block fitting

9. Install the new sealing washers onto the pilots

of the block fitting. Ensure that the washers
334249
10. Install the refrigerant hoses on the A/C

compressor. Secure the compressor with the
A/C compressor hose block fitting bolt.
11. Hold the block in place. Hand tighten the A/C
compressor block fitting bolt.
Tighten

13. Add the refrigerant to the system. Refer to
Testing.
15. Lower the cab.
229691
Evaporator Hose Assembly Replacement

Removal Procedure
Information.
2. Disconnect the negative battery cables.
Recharging.
Important: When removing the sealing washers,

prevent dirt or foreign materials from getting on
the surfaces of the following components:

The washers

The block fitting

Clean all of the sealing surfaces with a 229691
lint-free rag.
1998 -
MD-lsuzu
Manual HVAC
4. Remove the A/C compressor hose block

fitting bolt.

6. Remove the refrigerant hoses from the

A/C compressor.
229709
7998 -
MD-ISUZU
Manual 1-113
7. Remove the refrigerant hose from the A/C

condenser.
229705

A/C evaporator.
frame rail and the refrigerant hoses:
The hose clamp nuts
The washers

The bolts
The hose clamps
229714
Notices.
1. Install the hose clamps to the refrigerant hoses

and the frame rail. Secure the hose clamps
with the bolts, the washers and the nuts.
Tighten
Tighten the refrigerant hose clamp nuts to
30 N.m (22 Ib ft).
3. Install the new 0-ring seal in the A/C
evaporator end of the refrigerant hose.
229709
1998 -
MD-lsuzu
Manual HVAC

evaporator.
Tighten
evaporator to 32 N.m (24 Ib ft).
229714
6. Install the new 0-ring seal in the A/C condenser

end of the refrigerant.
condenser.
Tighten
condenser to 23 N.m (17 Ib ft).
229705

prevent dirt or foreign materials from getting on the
surfaces of the following components:
. The washers
The block fitting

9. Install the new sealing washers onto the pilots

of the block fitting. Ensure that the washers
334249
7998 -
MD-lsuzu
Manual 1-115
10. Install the refrigerant hoses to the A/C

compressor. Secure the refrigerant hoses with
the A/C compressor hose block fitting bolt.
11. Hold the block in place. Hand tighten the A/C
compressor block fitting bolt.
Tighten
13. Add the refrigerant to the system. Refer to
Testing.
15. Lower the cab.
229691
Receiver Dehydrator and Evaporator Hose

Assembly
Removal Procedure
2. Open the hood.

3. Secure the hood.
Recharging.
5. Remove the low pressure hose at the A/C
evaporator.
7. Remove the high pressure hose at the A/C
229705
evaporator.
bracket stud:
The A/C evaporator bracket nut

The A/C evaporator hose bracket
1998 -
MD-lsuzu
Manual HVAC
10. Remove the following components from the A/C

evaporator hoses:

The hose clamp nut

The washer
.
The bolt
.
The A/C evaporator hose clamp
229714
11. Remove the low pressure hose at the A/C

receiver/dryer or dehydrator.
13. Remove the high pressure hose at the A/C
condenser.
229717
2. Install the new 0-ring seal into A/C condenser
end of the evaporator hose.

and Notices.
4. Install the high pressure hose to the A/C
condenser.
Tighten
Tighten the A/C evaporator high pressure hose
fitting at the condenser to 18 N.m (14 Ib ft).
229705
1998 -
MD-lsuzu
Manual 1-117

evaporator end of the A/C evaporator hose.
7. Connect the low pressure hose to the A/C
evaporator.
Tighten
Tighten the A/C evaporator low pressure hose
fitting at the A/C evaporator to 32 N.m (24 Ib ft).
229714

evaporator end of the A/C evaporator hose.
evaporator.
11. Install the A/C evaporator hose clamps to the
A/C evaporator. Secure the clamps with the
washer, the bolt and the nut.
Tighten
Tighten the A/C evaporator hose clamp nut to
30 N.m (22 Ib ft).
12. Install the A/C evaporator hose bracket to the
A/C evaporator hose bracket stud. Secure the
hose bracket with the nut.
Tighten
Tighten the A/C evaporator hose bracket nut to
30 N.m (22 Ib ft).
13. Connect the negative battery cables. 229717
14. Close the hood.
Receiver Dehydrator Replacement

Removal Procedure
Information.
Recharging.
4. Remove the A/C receiver/dryer or dehydrator

electrical connector from the A/C receiver/dryer
or dehydrator pressure switch.
229717
7998 -
MD-ISUZU
Manual HVAC
5. Remove the A/C condenser tube.

7. Remove the A/C evaporator hose.

8. Remove the 0-ring seal from the A/C condenser.

clamp bolt.
from the A/C receiver/dryer or dehydrator clamp.
1. Install the A/C receiver/dryer or the dehydrator
into the A/C receiver/dryer or dehydrator clamp.

3. Install the new 0-ring seal.
229725

Notices.
4. Connect the A/C condenser tube to the A/C

receiver/dryer or dehydrator.
Tighten
Tighten the condenser tube to receiver/dryer or
dehydrator fitting to 15 N.m (11 Ib ft).

7. Install the A/C receiver/dryer and dehydrator
clamp bolt.
8. Install the A/C receiver/dryer or dehydrator
electrical connector to the A/C receiver/dryer or
dehydrator pressure switch.
229717 10. Add the refrigerant to the system. Refer to
1998 -
MD-lsuzu
Manual 1-119

Testing.
12. Lower the cab.
Thermal Expansion Valve Replacement

Removal Procedure
2. Open the hood.

3. Secure the hood.
Recharging.
5. Remove the right wiper arm linkage from the

wiper arm pivot.
6. Remove the low pressure hose from the A/C
evaporator.
7. Remove the low pressure hose.
8. Remove the 0-ring seal. 229714

9. Remove the high pressure hose.
10. Remove the high pressure hose 0-ring seal from
the A/C evaporator. Discard the 0-ring seal.
11. Remove the A/C evaporator core cover screws.
229734
1998 -
MD-lsuzu
Manual HVAC
12. Remove the A/C evaporator core cover.
229728
13. Remove the A/C spacer.

14. Remove the A/C evaporator.
15. Remove the screw and the clamp.
229730
16. Remove the A/C expansion valve from the low

pressure fitting.
17. Remove the A/C expansion valve 0-ring seal
from the low pressure fitting.
18. Discard the 0-ring seal.
19. Remove the A/C expansion valve from the A/C
evaporator core.
20. Remove the A/C expansion valve 0-ring seal
from the A/C evaporator core.
229736
1998 -
MD-lsuzu
Manual 1-121
1. Coat the new 0-ring seal with R-134a Swish

and Notices.
2. Install the new 0-ring seal and the expansion
valve to the A/C evaporator core.
Tighten
Tighten the A/C expansion valve fitting to
20N.m (15 Ib in).
4. Install the new 0-ring and A/C expansion valve

to the low pressure hose fitting.
Tighten
Tighten the A/C expansion valve low pressure
fitting to 15 N.m (11 Ib in).
229736
5. Install the screw and the clamp.
6. Fill the A/C evaporator core. Refer to

Refrigerant Oil Distribution Specifications.
229734
7. Install the A/C evaporator spacer.
229730
1998 -
MD-lsuzu
Manual HVAC
8. Install the A/C evaporator core cover.

9. Install the A/C evaporator core cover screws.
229728
11. Install the new 0-ring and the high pressure

hose to the A/C evaporator.
13. Install the new 0-ring and the low pressure
hose to the A/C evaporator.
Tighten
Tighten the high pressure hose fitting at
the A/C evaporator to 18 N.m (13 Ib in).
Tighten the low pressure hose fitting at
14. Push carefully on the right wiper arm linkage.
15. Close the hood.
16. Secure the hood.
Testing.
229714
A/C Temperature Sensor Replacement

Removal Procedure
1. Raise the hood. Support the hood.

3. Disconnect the electrical connections.
4. Remove the screw.
229943
1998 -
MD-lsuzu
Manual HVAC
Condenser Fan Replacement

Removal Procedure
Information.
3. Remove the A/C condenser fan electrical
connector from the A/C condenser fan.
4. Remove the following components from the A/C
condenser:
4.1. The four bolts
4.2. The A/C condenser fan
229722
1. Install the A/C condenser fan to the A/C
condenser.
2. Secure the A/C condenser fan with the four bolts.
3. Install the A/C condenser fan electrical
connector to the A/C condenser fan.
5. Lower the cab.
229722
Condenser Replacement
Removal Procedure
Information.

Recharging.
4. Remove the A/C condenser fan from the A/C

condenser. Refer to Condenser Fan
Replacement.
5. Remove the A/C condenser hose from the A/C
condenser.
229722
1998 -
MD-lsuzu
Manual 1-125
6. Remove the A/C evaporator hose.

7. Remove the 0-ring seal from the A/C
condenser. Discard the 0-ring seal.
229705
8. Remove the A/C condenser tube.

9. Remove the 0-ring seal from the A/C
receiver/dryer or the dehydrator. Discard the
0-ring seal.
229717

electrical connector from the A/C receiver/dryer
or dehydrator pressure switch.
clamp bolt.
from the A/C receiver/dryer or dehydrator clamp.
13. Remove the A/C condenser brace insulator nut
and the washer.
frame rail:
14.1. The nuts from the two A/C condenser
mounting brackets
14.2. The bolts

14.3. The insulators
14.4. Six washers
14.5. The A/C condenser
229725
1998 -
MD-lsuzu
Manual HVAC

A/C condenser braces:
15.1. The nut
15.2. The washer
15.3. The A/C condenser insulator
A/C condenser:
16.1. The nut
16.2. The bolt
16.3. The washers
16.4. The bracket
16.5. The upper A/C condenser brace
A/C condenser:
17.1. The nut
17.2. The bolt
17.3. The washers
17.4. The bracket
17.5. The lower A/C condenser brace
A/C condenser:
18.1. Two screws
18.2. The A/C receiver/dryer or dehydrator clamp
1. Install the A/C receiver/dryer or dehydrator
clamp to the A/C condenser. Secure the clamp
with two screws.
229725
1998 -
MD-ISUZU
HVAC HVAC Systems with A/C
Manual 1-127
Notices.
2. Install the lower A/C condenser brace to the

A/C condenser. Secure the brace with the
2.1. The bolt

2.2. The washers
2.3. The bracket
2.4. The nut
Tighten
Tighten the lower A/C condenser brace
nut to 70 N.m (51 ft Ib).
3. Install the upper A/C condenser brace to the
A/C condenser. Secure the brace with the
3.1. The bolt

3.2. The washers
229722
3.3. The bracket
3.4. The nut
Tighten
Tighten the upper A/C condenser brace
nut to 70 N.m (51 ft Ib).
4. Install the A/C condenser insulator to the A/C

condenser braces. Secure the insulator with a
washer and a nut.
Tighten
Tighten the A/C condenser insulator nut to
35 N.m (26 ft Ib).
5. Install the A/C condenser to the frame rail.
Secure the condenser with the following
components:
5.1. Two A/C condenser mounting bracket
insulators
5.2. Six washers

5.3. Two bolts
5.4. The nuts
Tighten
Tighten the A/C condenser insulator
bracket nuts to 24 N.m (18 ft Ib).
6. Install the A/C condenser brace insulator
washer and the nut.
Tighten
Tighten the A/C condenser insulator nut to
35 N.m (26 ft Ib).
1998 -
MD-lsuzu
Manual 1-131

229889
Blower Motor and Fan Replacement

Removal Procedure
229889
214669
1998 -
MD-lsuzu
Manual HVAC

6. Remove the blower motor cooling tube.
7. Remove the blower motor screws.
8, Remove the blower motor and fan.
1. Install the blower motor and fan.
229931
(998 -
MD-ISUZU
Manual 1-133
2. Install the blower motor screws.
3. Install the blower motor cooling tube.
229897
214669

229889
1398 -
MD-lsuzu
Manual HVAC
HVAC Module Assembly Replacement

Removal Procedure
2. Remove the instrument panel. Refer to IP Carrier

3. Remove the right heater core. Refer to Heater
Core Replacement (Right).
4. Remove the A/C Temperature Sensor
connectors screw.
5. Remove the left heater core. Refer to Heater
Core Replacement (Left).
6. Disconnect the A/C Temperature Sensor
229927 7. Remove the A/C Temperature Sensor connectors.

8. Remove the air conditioning evaporator. Refer
to Evaporator Core Replacement.
9. Disconnect the blower motor resistor electrical

connectors.
10. Disconnect the blower motor electrical connectors.
11. Remove the heater vent module nuts.
12. Remove the right heater vent module.
13. Remove the left heater vent module.
229929
1998 -
MD-lsuzu
Manual 1-135
1. Install the left heater vent module.
229929
2. Install the right heater vent module.

3. Install the heater vent module nuts.
4. Install the blower motor electrical connectors.
5. Install the blower motor resistor electrical
connectors.
6. Install the air conditioning evaporator. Refer to
Evaporator Core Replacement.
7. Install the A/C Temperature Sensor connectors.
8. Connect the A/C Temperature Sensor
9. Install the A/C Temperature Sensor connectors
screw.
10. Install the heater cores. Refer to Heater Core
Replacement (Right).
Replacement.
Battery Replacement in Engine Electrical. 229927
Evaporator Core Replacement

Removal Procedure
2. Open the hood.

3. Secure the hood.
Recharging.
5. Remove the right wiper arm linkage from the

wiper arm pivot.
6. Remove the low pressure hose from the A/C
evaporator.
7. Remove the low pressure hose 0-ring seal from
the A/C evaporator. 229714

1998 -
MD-lsuzu
Manual HVAC
9. Remove the high pressure hose.

10. Remove the high pressure hose 0-ring seal
from the A/C evaporator.
12. Remove the A/C evaporator core cover screws.

13. Remove the A/C evaporator core cover.
229728
14. Remove the A/C evaporator spacer.
229730
1998 -
MD-ISUZU
Manual 1-137
15. Remove the A/C evaporator.
229734
1. Fill the A/C evaporator. Refer to Refrigerant Oil
Distribution Specifications.
229734
2. Install the A/C evaporator spacer.
229730
1998
MO-lsuzu
Manual HVAC
3. Install the A/C evaporator core cover.
4. Install the A/C evaporator core cover screws.

229728

evaporator.
and Notices.
10. Install the low pressure hose to the A/C
evaporator.
Tighten
Tighten the high pressure hose fitting at
Tighten the low pressure hose fitting at
11. Push carefully on the right wiper arm linkage.
12. Close the hood.
13. Secure the hood.
229714
Testing.
1998 -
MD-lsuzu
Manual 1-139
Heater Core Replacement (Right)

Removal Procedure
Cooling.
229937

229939
9. Remove the right heater core.
229941
1998 -
MO-lsuzu
Manual HVAC
1. Install the right heater core.
229941
229939


10. Close the hood.
229937
1998 -
MD-lsuzu
Manual 1-141
Heater Core Replacement (Left)

Removal Procedure
Cooling.

229937

229939
9. Remove the left heater core.
229941
1998 -
MD-lsuzu
Manual HVAC
1. Install the left heater core.
229941
229939

10. Close the hood.
229937
1998 -
MD-lsuzu
Manual 1-143
Heater Pipes Replacement (Inlet)

Removal Procedure
Cooling.
2. Remove the inlet hose clamp to the engine pipe.
3. Remove the hose clamps from the heater core.
4. Remove the inlet pipe mounting bolts, washers
and nuts.
5. Remove the inlet pipe clamp on the frame.
290969
6. Remove the inlet pipe.
^
220038
Notices.
1. Push the pipe into the heater inlet hose

connector (1) until the retainer locking tabs
lock. (2,3 ) Pull back on the hose to check for
proper engagement.
Tighten
Quick Connect Heater Inlet Connector to
35 N.m (26 Ib ft).
^
220038
1998 -
MD-lsuzu
Manual HVAC
2. Install the inlet pipe.

3. Install the pipe clamps on the frame.
4. Install the inlet pipe mounting bolts, washers
and nuts.
5. Install the inlet hose clamp from the heater core.
6. Install the inlet hose clamp to the engine pipe.
290969
Heater Pipes Replacement (Outlet)

Removal Procedure
Cooling.
2. Remove the hose clamp from the heater core.

3. Remove the hose clamp from the radiator hose.
4. Remove the mounting bolt.
5. Remove the pipe clamp on the frame.
6. Remove the outlet pipe.
290964
1998 -
MD-lsuzu
Manual 1-145
Installation procedure
1. Install the outlet pipe.
2. Install the clamp on the frame.
3. Install the mounting bolt.

4. Install the hose clamp from the radiator hose.
5. Install the hose clamp from the heater core.
Filling Cooling System (Filling) in Engine
Cooling.
Passenger Compartment Air Filter

Replacement
Removal Procedure
1. Open the hood.
2. Secure the hood.

3. Hold the tap located at the bottom of the filter.
Pull the tap carefully.
4. Rinse the filter with clean water on both sides.
229686
1998 -
MD-lsuzu
Manual HVAC
1. Push carefully on the filter. Install the filter in
the heater module.
2. Close the hood.
\ ^^ 9
229686
Control Assembly Replacement

Removal Procedure
214649

229887
7995 -
MD-lsuzu
Manual 1-147
229887

214649
Blower Switch Replacement

Removal Procedure
214649
1998 -
MD-ISUZU
Manual HVAC

=^
229887
229887

214649
1998 -
MD-lsuzu
Manual 1-149
Mode Actuator Replacement

Removal Procedure
229889

4. Remove the instrument panel lower trim.
214669
5. Disconnect the audio system. Refer to Radio

229697
1998 -
MD-lsuzu
Manual HVAC
229904
7. Remove the heater module (right side).
229927
7998 -
MD-ISUZU
Manual 1-151
8. Remove the mode actuator.
229907
1. Install the mode actuator.
229907
2. Install the heater module (right side).
229927
1998 -
MD-lsuzu
Manual HVAC
229904
4. Connect the audio system. Refer to Radio

229897
1998 -
MD-lsuzu
Manual 1-153
5. Install the instrument panel lower trim.
214669

229889
Air Inlet Actuator Replacement

Removal Procedure

229889
1998 -
MD-lsuzu
Manual HVAC
214669
229897
1998 -
MD-ISUZU
Manual 1-155
229904
7. Remove the air inlet actuator.
229948
1998 -
MD-ISUZU
Manual HVAC
1. Install the air inlet actuator.
229948
229904
1998 -
MD-lsuzu
Manual 1-157
229897
214669

229889
1998 -
MD-ISUZU
Manual HVAC
Temperature Actuator Replacement

Removal Procedure
229889
214669
229897
1998 -
MD-lsuzu
Manual 1-159
229904
7. Remove the temperature actuator.
229948
1998 -
MD-ISUZU
1 -160 HVAC Systems with A/C -
Manual HVAC
1. Install the temperature actuator.
229948
229904
1998 -
MD-lsuzu
Manual 1-161
229897
214669

229889
1998
MD-lsuzu
Manual HVAC
Air Distributor Duct Replacement (Lower)

Removal Procedure
1.Disconnect the negative battery cable. Refer to

3. Remove the air distributor duct lower screws.
4. Remove the air distributor duct lower bolt.
229904
2. Install the air distributor lower duct bolt.

3. Install the air distributor lower duct screws.
229904
1998 -
MD-lsuzu
Manual 1-163
Air Distributor Duct Replacement (Upper)
Removal Procedure

3. Remove the air distributor upper duct screws.

4. Remove the air distributor upper duct.
229918
1. Install the air distributor upper duct.
2. Install the air distributor upper duct screws.

229918
1998 -
MD-lsuzu
Manual HVAC

Operating Modes
( )( X )( X ) ( ) ( I
[ ^ ^ (g) (^ ^
,^ ,^ A/C
COLDC ^-==^-^ )HOT J^ OFF

'
1 2 3 4
^ ^
V.
The control assembly

^fl^[B^
in
the instrument panel
^/
Intermediate positions of the temperature lever result

229857
contains the following components: in a mixture of heated and unheated air to provide
A blower switch more moderate air temperatures. This lever operates

the temperature actuator. As a result, this lever

Mode switches
moves the temperature control door.
A temperature lever
Vent Mode
The controls are lit when the headlamps are on.
Electrical power is provided by the control panel With the vent switch in the ON position, the inlet air
lighting circuit from the control panel harness. actuator is activated. This causes the
recirculating/fresh air door to open completely and air
The mode control switches allow the driver to control is discharged from the upper air outlets. As a result,
the direction and quantity of air through different the air coming from the upper air outlets should be
outlets. nearly the same temperature as the outside air.
Brightness of the illumination is controlled by the
Bi-Level Mode
instrument panel dimmer switch. The control
With the Bi-Level switch in the ON position, the mode
assembly bulbs are in parallel with the radio bulb
and the instrument cluster illumination bulbs. actuator is activated. This causes the mode control
door to open halfway. The airflow is divided between
Fan Control Switch the upper air outlets and the floor air outlets.
Air quantity is controlled by the four-position blower Floor Mode

fan control switch. The blower fan control switch With the Floor switch) in the ON position, the mode
provides a choice of various blower motor speeds. actuator is activated. This causes the mode control
door to open completely. The majority of airflow is
Temperature Lever routed to the floor while the remaining airflow is
When the temperature lever is in the COLD or routed to the windshield outlets.
extreme left end of the slot, all of the air delivered
by the heater system is unheated. The temperature Floor/Defrost Mode
actuator and the temperature control door are With the Floor / Defrost switch in the ON position,
positioned to stop all of the airflow through the the mode actuator is activated. This causes the
heater cores so only unheated air is sent up in the mode control door to open halfway. Half of the
heater module. airflow is delivered to the floor while the other half is
delivered to the windshield outlets.
When the temperature lever is in the HOT or
extreme right end of the slot, almost all of the air Defrost Mode
delivered by the system is heated. The temperature With the Defrost switch in the ON position, the mode
actuator and the temperature control door is actuator is activated. This causes the mode control
positioned to open so that all of the airflow through door to open completely. The majority of the airflow
the heater cores is sent up in the heater vent is routed to the windshield outlets while the
module. remaining airflow is routed to the floor.
1998 -
MD-lsuzu
Manual 1-165
Max/Rec/Rc Mode When the R-134a refrigerant changes from a liquid to

a gas in the A/C evaporator, the vehicle cab cools.
With the Max /Rec/ Re switch (2) in the ON position,
theair inlet actuator is activated. This causes the air The air that passes through the A/C evaporator
inlet door to close completely, causing very little transfers heat to the R-134a refrigerant. The R-134a
outside air (that is needed for the outside air system) refrigerant absorbs the heat and changes into a gas.
from coming in. The majority of airflow is not outside The blower motor circulates the air in the cab.
air. The air is recirculated throughout the cab.
A/C Mode
With the A/C switch (3) in the ON Position, the air
conditiioning will work.
Air Distribution System Description

The HVAC module contains a series of air doors.
These doors are hinged parts that direct the airflow
through various sections of the HVAC module. This
action provides the proper airflow for the selected
operating mode. Each air door is controlled by an
actuator.
Ducts and Outlets

A system of ducts and outlets directs air to the
passenger compartment.
If the air output is poor, inspect the following areas
for obstruction:
The defroster

The heater
The air conditioning
The vent ducts
Refrigeration System Description

(With A/C)
The system contains a refrigerant. The refrigerant is
either a gas or a liquid, depending on the

temperature and the pressure. The refrigerant is a
heat exchange medium.
Heat is required to change the liquid refrigerant 229659
(134a) into a gas or vapor.
1998 -
MD-ISUZU
Manual HVAC
229652
The following steps occur in the refrigerant cycle: 7. The liquid refrigerant flows through the A/C
1. The refrigerant cycle starts at the A/C
expansion valve (5).
compressor (10). 8. The refrigerant changes to a low pressure, low
The refrigerant is a low pressure, low temperature liquid in the A/C evaporator (2).
temperature vapor when it enters the
9. Warm inside air flows through the cooler A/C
compressor.
evaporator core or fins (3).
2. The refrigerant is compressed to a high
pressure, high temperature vapor. The warm air transfers heat to the low pressure,
low temperature liquid in the A/C evaporator.
3. The vapor flows through the A/C
condenser tube. 10. The low pressure vapor returns to the A/C
4. The vapor transfers heat to the cooler air that compressor.
is passing through the A/C condenser cooling
11. The cycle begins again.
fins (8).
5. The high pressure, high temperature vapor

changes into a high pressure, high temperature
liquid.
6. The high pressure liquid passes through the
A/C receiver/dryer or dehydrator.
The following actions occur in the A/C
receiver/dryer or dehydrator (7):
6.1. A screen filters the refrigerant.
6.2. A desiccant removes moisture from the
refrigerant.
6.3. The A/C receiver/dryer or dehydrator also
stores the refrigerant.
(998 -
MD-lsuzu
Manual 1-167

(Without A/C)
229842
Hot coolant comes from the engine and is directed Outside air is drawn from the plenum into the heater
through the heater cores and returned to the cooling vent module by the blower motor fan. Additional
system when the engine is running (under normal outside air (called ram air) is forced into the heater
operating conditions). vent module by the forward movement of the vehicle.
Within the heater vent module, the air is heated as
The heater vent module contains components that
required, then routes through ducts to the proper
heat the air flowing through. The air is directed to outlets for discharge into the passenger
the proper ducts and outlets. compartment. A control assembly in the instrument
The heater system provides the following features: panel allows the operator to control the following
conditions:

Heated ram air

Blower speed

Power ventilation
Mode of operation

system
1998 -
MD-lsuzu
Manual HVAC
Heater System Description
229842
Hot coolant comes from the engine and is directed Refrigerant R-134a
through the heater cores and returned to the cooling
system when the engine is running (under normal Caution: Avoid breathing A/C Refrigerant-134a
operating conditions). and lubricant vapor and mist. Exposure may
irritate eyes, nose and throat. To remove R-134a
The heater vent module contains components that
from the A/C system, use service equipment
heat the air flowing through. The air is directed to certified to meet the requirements of SAE J2210
the proper ducts and outlets.
(R-134a recycling equipment). If accidental
The heater system provides the following features: system discharge occurs, ventilate work area

Heated ram air before resuming service. Additional health and
safety information may be obtained from
.
Power ventilation
refrigerant and lubricant manufacturers.
Refrigerant performs the following functions in the air
Outside air is drawn from the plenum into the heater
conditioning system:
vent module by the blower motor fan. Additional
outside air (called ram air) is forced into the heater Absorbs heat
vent module by the forward movement of the vehicle.
Carries heat
Within the heater vent module, the air is heated as

Releases heat
required, then routes through ducts to the proper
These vehicles use Refrigerant-134a (R-134a).
outlets for discharge into the passenger
Refrigerant-134a is a nontoxic, nonflammable, clear,
compartment. A control assembly in the instrument
colorless liquefied gas.
panel allows the operator to control the following
conditions:

Blower speed

Mode of operation

system
1998 -
MD-lsuzu
Manual 1-169
Handling Refrigerant R-134a Use the following steps in order to recover the
system of all Refrigerant 134a:
Caution: Avoid breathing A/C Refrigerant-134a
and lubricant vapor and mist. Exposure may 1. Proceed very cautiously regardless of the
irritate eyes, nose and throat. To remove R-134a gage readings.
from the A/C system, use service equipment 2. Open the fitting very slowly.
certified to meet the requirements of SAE J2210 3. Keep the hands and the face away from
(R-134a recycling equipment). If accidental the fitting in order to prevent injury.
system discharge occurs, ventilate work area
4. If pressure is noticed when a fitting is
before resuming service. Additional health and
loosened, allow the pressure to bleed off
safety information may be obtained from slowly.
refrigerant and lubricant manufacturers.
Notice: Never use alcohol to remove moisture from
Important: the refrigeration system. Damage to the system

Use only the approved lubricant for the R-134a components could occur.
system and the R-134a components. If lubricants
other than those specified are used, compressor

Immediately cap any refrigerant lines that are
failure may occur. Coat all of the fittings and the opened to the atmosphere. This action prevents
the entrance of moisture and dirt.
0-ring seals with a clean approved refrigerant oil.
This action will provide a leak-proof seal and to Dirt and moisture may cause internal A/C
aid in assembly and disassembly compressor wear or plugged lines in the
following areas:

Do not store or heat the refrigerant containers
above 125-F (52-C). -
The A/C condenser
Do not heat a refrigerant container with an -
The A/C evaporator core
open flame. If the container must be warmed, -
The A/C expansion (orifice) tubes
place the bottom of the container in a pail of -
The A/C compressor inlet screens
warm water.

Remove the sealing caps from the

Do not drop, puncture, or incinerate the subassemblies just before making the
refrigerant containers. connections for final assembly.

Refrigerant will displace oxygen. Work in Apply a small amount of clean 525 viscosity
well-ventilated areas in order to prevent refrigerant oil on all of the tube and hose joints.
suffocation.
Do not introduce compressed air to any
refrigerant container or refrigerant component.
The action may cause the contamination of the
refrigerant.
. If it is necessary to carry a container of Dot
CFR Refrigerant-134a in a vehicle, do not carry
it in the passenger compartment.
Handling of Refrigerant Lines and Fittings

Important: Before opening the refrigeration system,
ensure that the work area is well-ventilated. Do not
conduct welding or steam-cleaning operations on or
near the following areas:
The refrigeration system lines

Other air conditioning components

Ensure that all of the metal tubing lines are
free of dents or kinks that may cause line
restriction. Line restriction may cause the loss
of system capacity. 221228
Do not bend the flexible hose lines to a radius Use new 0-ring seals dipped in 525 viscosity
of less than 4 times the diameter of the hose. oil when assembling joints. The oil aids in

Do not allow the flexible hose lines to come assembly and helps provide a leakproof joint.
within 6.5 mm (2.5 in) of the exhaust manifold. Ensure that the 0-ring seals and the seats are
in perfect condition. A burr or a piece of dirt on
Regularly inspect the flexible hose lines for
the 0-ring seal may cause a refrigerant leak.
leaks or brittleness. Replace the lines with new
lines if deterioration or leaking is found.

When disconnecting any fitting in the
refrigerant system, recover the system of
all Refrigerant 134a.
1998 -
MD-lsuzu
Manual HVAC
Use the following general practices in order to

ensure chemical stability in the system:

Whenever a hose connection is disconnected,
wipe away any dirt or oil at or near the
connection. This action prevents dirt from
entering the system.

Cap, plug or tape both sides of the connection
as soon as possible in order to prevent the
entrance of dirt and moisture. (Remember that
air contains moisture. Air that enters any part of
the refrigeration system will carry moisture with
it. The exposed surface will collect the moisture
quickly.)

Ensure that the following components remain
clean and dry:
All of the tools, including the Manifold
Gage Set
All of the replacement parts
221226

When adding Polyalkaline Glycol (PAG)
refrigerant oil, ensure that the container/transfer
Important: Use the proper wrenches in order to
tube through which the oil will flow is clean and
make connections on the 0-ring seal fittings. dry. Refrigerant oil must be as moisture-free as
Using improper wrenches may damage the possible.
connection.
Gather all of the necessary tools and components

Use a wrench in order to back up the opposing before opening an air conditioning system. This
fitting. This action will prevent distortion of the action will ensure that a minimum amount of time
connecting lines or the components. is used to perform the operation. Do not leave

Use three different wrenches in order to the air conditioning system open to the
simultaneously hold the following components atmosphere any longer than necessary.
when connecting the flexible hose connections:
Whenever the air conditioning system is
-
The swaged fitting opened, properly evacuate the air conditioning
-
The flare nut system before recharging the system.
-
The coupling that is attached to the flare nut Evaporator Description
This action prevents turning in the fitting and The A/C evaporator cools, drys and cleans the air
damage to the seat. that enters the passenger compartment. The A/C
Tighten tubing connections to the specified evaporator case is insulated in order to prevent
torque. Refer to Fastener Tightening sweating.
Specifications. The following series of actions occurs in the A/C
evaporator:
Maintaining Chemical Stability
1. Refrigerant enters the A/C evaporator as a low
The life and efficient operation of the air conditioning
pressure liquid.
system depends upon the chemical stability of the
refrigerant system. 2. The liquid boils (vaporizes) at this low pressure.
The following conditions may result if foreign material 3. The liquid absorbs heat.
contaminates the refrigeration system: The heat comes from the warmer outside air
A change in the stability of Refrigerant-134a

that passes through the A/C evaporator fins.
and Polyalkaline Gylcol (PAG) refrigerant oil 4. The air that will be directed into the passenger
A change in the pressure-temperature compartment is cooled.
relationship 5. As the heat is transferred to the A/C

Reduced efficiency of the system evaporator, moisture from the air condenses the
surface of the evaporator.
Internal corrosion
6. The moisture drains off.

Abnormal wear of moving parts
The moisture carries dust and pollen as it drains.
A water drain port is located in the bottom of
the housing.
1998 -
MD-lsuzu
Manual 1-171
The temperature of the A/C evaporator must be high Compressor Description

enough so that the water collecting on the surface
will not freeze. Frozen water on the surface may
The air conditioning compressor is a belt-driven six
cylinder swash plate type. There are three double
restrict the passage of air.
end positions that form six pumping chambers.
The following components control the temperature
Refrigerant-134a flow is controlled by a reed valve
along with the A/C evaporator:
and internal passages.
The A/C expansion valve
Front and rear cylinder heads hold the valve and

The thermostat plates to the main body and are secured by six bolts.
The A/C evaporator is located in the heater module, Compressor oil mixed with refrigerant lubricates the
underneath and behind the instrument panel. A/C compressor. Compressor cycling is determined by
an electrically actuated armature and other controls.
Condenser Description
The A/C condenser includes the following Control Assembly Description
components:
The coils
The cooling fins
The coils carry the refrigerant.
The cooling fins provide a rapid transfer of heat.
The air passing through the A/C condenser cools the
high-pressure refrigerant vapor. This action causes
the air to condense into a liquid.
Accumulator Description
The sealed A/C accumulator assembly is connected to
the A/C evaporator outlet pipe. The A/C accumulator
assembly functions as a liquid/vapor separator.
The A/C accumulator assembly receives the following -==^g=R
items from the A/C evaporator:
The refrigerant vapor

Some liquid
. The refrigerant from the A/C evaporator
229887
It only allows refrigerant vapor and oil to continue on
to the A/C compressor. The air conditioning operates only when the A/C
A desiccant may be present at the bottom of the A/C button on the control assembly is ON.
accumulator. The desiccant acts as a drying agent. The following controls on the controller maintain the
An oil bleed hole is also located near the bottom of temperature of the passenger compartment:
the A/C accumulator outlet pipe. The oil bleed hole The temperature selector
provides an oil return path to the A/C compressor.
The fan control switch
1998 -
MD-lsuzu
Manual HVAC
Ventilation Description
229843
Within the heater vent module is a series of air

doors. These air doors are hinged parts that direct
the airflow through the various sections of the heater
vent module in order to provide the proper airflow for
the selected operating mode.
229846
Each air door is controlled by an actuator. This information is compared by the thermounit. The
results in output are used in order to complete the
Relays and Sensors Description following actions:

Operate the A/C compressor relay.
Electronic Thermostat
The thermostat consists of the following components:

Turn the A/C compressor clutch on and off.
The thermosensor These actions prevent A/C evaporator freeze up.

The thermostat unit A/C Dual Pressure Switch
These components electrically reduce the noise An A/C dual pressure switch is located on the A/C
caused by system operation. receiver/dryer or dehydrator.
The electronic thermosensor is mounted at the The
The switch is normally closed. The switch will open
electronic thermosensor senses the temperature of
the cool air from the A/C evaporator. The the circuit to the A/C compressor clutch coil if the
refrigerant pressure becomes too high or too low.
temperature signals are input to the thermostat unit.
1998 -
MD-lsuzu
Manual 1-173
ACR4 Procedures Motor speed is controlled by routing the blower

motor ground through dropping resistors.
Initial Setup
The Blower Motor Speed Switch supplies ground
Refer to the manufacturer's instructions for all initial through one of the resistors for all of the speeds
setup procedures. but HIGH.
The following conditions exist when the Blower Motor
Operational Setup
Switch is the LO position:
Voltage is applied from the switch contacts
through the BLU/WHT (180,196) wire to the
Blower Motor Resistor.
.
The Blower Motor current flows through all
three resistors.

Grounding is provided through the following
components:

The switch common terminal
.
The HVAC controller module

Current flow is established.
The Blower Motor operates.

The voltage drops through the three resistors in
the Blower Motor Resistor.
The drop in voltage limits motor operation to
the lowest possible speed.
The following conditions exist when the Blower Motor
Switch is in the MED LO position:
277008
Voltage is applied to the Blower Motor Resistor
through the BLU/BLK (181, 195) wire.
Caution: Always wear goggles and gloves when
doing work that Involves opening the refrigerant
Current flows through two resistors in order to
system. If liquid refrigerant comes Into contact get to the motor.
with the skin or eyes, injury may result.
The motor operates at a faster speed than
Caution: Use only authorized 23-kg (50-lb.) through all three resistors.
refutable tanks (J 39500-50). Use of other tanks The following conditions occur when the Blower
could cause personal injury and void the Motor Switch is in the MED HI position:
warranty.
Voltage is applied to the Blower Motor Resistor
Notice: Refrigerant-134a systems have special through the BLU/YEL (182/194) wire.
fittings (per SAE specifications) to avoid
Current flows through only one resistor in order
cross-contamination with Refrigerant-12 systems. Do to get to the motor.
not attempt to adapt this unit to Refrigerant-12 . The increased voltage causes the motor to
systems as severe system failure will result.
operate at a faster rate.

Connect the following hoses to the ACR4 unit: The following conditions exist when the Blower Motor

The high side (Red) hose Switch is in the HI position:

The low side (Blue) hose
Voltage is applied directly to the Blower Motor
through the BLU/RED (183/192) wire.
.
Route the hoses through the hose reel bracket
grommets.
Current flows directly to the motor.
.
Maximum voltage is applied to the motor. The
HVAC Blower Controls Circuit Description
motor operates at the fastest possible speed.
Blower Motor HVAC Temperature Actuator
The Blower Motor controls supply ground to the The HVAC Temperature Actuator controls the amount
motor through the following components: of engine coolant that is available to the heater core.
1. The Blower Speed Switch contacts The operator heat selection lever position is
2. The Blower Resistor translated into an electrical signal.
Circuit Breaker #6 can supply battery voltage to the The Temperature Actuator controls a motor operated
Blower Relay Coil when the ignition switch is in the valve in the engine coolant line. The position of the
RUN position through the BRN (198) wire. valve is changed in response to the operator
Circuit Breaker #24 provides relay contact power for temperature selection. The valve is driven open in
the operation of the Blower Motor. The relay contact order to provide more heat energy. The valve is
driven closed for less heat.
power is provided when the ignition is in the RUN
position.
1998 -
MD-lsuzu
Manual HVAC
HVAC Compressor Controls Circuit Thermo Switch

Description The Thermo Switch provides additional protection
from icing conditions in the evaporator core by
A/C Compressor Clutch
performing the following actions:
The A/C Compressor is belt driven. The pulley of the
Sensing the evaporator core temperature.
compressor rotates whenever the engine is
Removing ground from the compressor relay coil
operating. The compressor only operates when the

compressor clutch has been energized. The clutch is when the temperature falls below a set value.
engaged when the Compressor Relay passes current HVAC Air Delivery Circuit Description
to the Compressor Clutch Coil.
HVAC Mode Actuator
Compressor Relay
The HVAC Mode Actuator operates with the HVAC
The Compressor Relay receives two sources of Mode Switch.
voltage:
The following modes are the HVAC modes:
Circuit Breaker #20 provides voltage at all times
. VENT
to Compressor Relay terminal 30 through the
GRN/RED (207) wire. . BI-LEVEL
.
When the Ignition Switch is in the RUN . FLOOR
position, Circuit Breaker #6 provides power to . FLOOR/DEFROST
the Compressor Relay coil from the Blower .DEFROST
Relay contacts, through the LT GRN (210) wire.
The HVAC Mode Actuator Motor operates when an
The Compressor Relay contacts are normally open. HVAC mode change is selected.
When the Compressor Relay is energized, the
The HVAC Mode Actuator Motor drives the dampers
contacts close. The contacts apply voltage through
the LT BLU (203,208) wire to the A/C Compressor open or closed in the HVAC ductwork segments.
Clutch Coil. Because the A/C Compressor Clutch This action provides the correct air handling
Coil is grounded internally through its case, the coil mode path.
is energized when voltage is applied.
Vent Mode
The Compressor Relay is energized when a ground The recirculating/fresh air actuator is activated when
path is provided for the relay coil through the
the switch is in the ON position.
GRN/RED (213) wire. The Air Conditioning Mode
Switch provides this ground path through the Thermo
The following actions occur when the
recirculating/fresh air actuator is activated:
Switch.
The Thermo Switch performs the following functions:
The recirculating/fresh air door opens
completely.

Senses the temperature of the interior vehicle air
Air is discharged from the upper air outlets.
Cycles to ground when the temperature goes
As a result, the temperature of the air that is
above the set value
released from the upper air outlets is close to the
This action energizes the Compressor Relay coil.
temperature of the outside air.
The A/C Pressure Cutoff Switch cycles the
compressor off when the following conditions exist: Bi-Level Mode
The compressor is otherwise enabled. The mode actuator is activated when the switch is in
the ON position.
The freon in the system reaches a set pressure.
This action causes the mode control door to open
A/C Pressure Cutoff Switch halfway.
The A/C Pressure Cutoff Switch performs the Airflow is divided between the upper air outlets and
following two functions: the floor air outlets.
The high pressure cutout section of the switch Floor Mode
is normally closed during the operation of the
A/C Compressor. The mode actuator is activated when the switch is in
the ON position.
The switch opens if the pressure in the A/C
This action causes the mode control door to open
refrigerant lines is too high.
completely.
This action interrupts the power to the A/C
Most of the airflow is routed to the floor. The rest of
compressor relay.
the air is routed to the windshield outlets.
The low pressure cutout section of this switch
cycles on and off in response to evaporator Floor/Defrost Mode
temperature. The mode actuator is activated when the switch is in
The switch opens just above the freezing point. the ON position.
This action prevents the system from freezing. This action causes the mode control door to open
The temperature switch closes as the evaporator halfway.
temperature rises. This action allows the Half of the airflow is routed to the floor. The other half
compressor to run and to maintain system cooling. of the airflow is delivered to the windshield outlets.
1998 -
MD-lsuzu
Manual 1-175
Defrost Mode A/C Compressor Clutch

The mode actuator is activated when the switch is in The A/C Compressor is belt driven and the
the ON position. compressor's pulley rotates whenever the engine is
This action causes the mode control door to open operating. The compressor only operates when the
completely. compressor clutch has been engaged when the
Compressor Relay passes current to the Compressor
Most of the airflow is routed to the windshield
Clutch Coil.
outlets. The rest of the airflow is routed to the floor.
HVAC Recirculating Fresh Air Actuator Compressor Relay

The Compressor Relay receives two sources of
The HVAC Recirculating Fresh Air Actuator controls
voltage. Circuit Breaker #20 provides voltage at all
the amount of fresh air that enters the vehicle during
times to the Compressor Relay terminal 30 through
the various HVAC modes.
the CKT207 (GRN/RED) wire. When the Ignition

The VENT mode provides 100 percent fresh air Switch is in the RUN position, Circuit Breaker #6
from outside of the vehicle. provides power to the Compressor Relay coil from
. The MAX A/C and the MAX HEAT modes the Blower Relay Contacts, through the CKT210
provide a minimum of fresh air to the vehicle. (LT GRN) wire. When the Compressor Relay is
These modes recirculate most of the vehicle energized, the normally-open contacts close to apply
inside air in order to quickly cool or warm the voltage through the CKT203, 208 (LT BLU wire to
the A/c Compressor Clutch Coil. Since the A/C
interior.
Compressor Clutch Coil is grounded internally
HVAC Temperature Actuator through its case, the coil is energized when voltage
is applied.
The HVAC Temperature Actuator controls the amount
of air from the Blower Motor that will be routed The Compressor Relay is energized when a ground
through either or both of the following components: path is provided for the relay coil through the CKT213
(GRN/RED) wire. The Air Conditioning Mode Switch
The A/C Evaporator Core
provides the ground path through the Evaporator

The Heater Core Temperature Sensor. The Evaporator Temperature
The position of the operator temperature selection Sensor senses temperature and cycles to ground,
lever is translated into an electrical signal. which energizes the Compressor Relay Coil, when the
The temperature actuator controls a series of motor temperature goes above the set value. The A/C High
operated valves. The valves are driven into different Pressure Cutoff Switch will cycle the compressor off
positions. The positions provide more heating or while otherwise enabled, when the freon in the system
cooling in response to the temperature selection. reaches a set pressure.
HVAC Compressor/Condenser Fan Circuit A/C Pressure Cutoff Switch

Description The A/C Pressure Cutoff Switch provides two functions:
The high pressure cutout section of this switch is
A/C Condenser Fan normally closed during operation of the A/C
When the Ignition Switch is in the RUN position compressor. If pressure in the A/C refrigerant
voltage is applied to the coil of the blower Relay 3 lines goes too high, this switch will open,
through Circuit Breaker #6. Since the coil of Blower interrupting power to the A/C Compressor Relay.
Relay is grounded at all times through G105, the . The low pressure cutout section of this switch
Relay will energized, close the relay contacts. cycles on and off in response to refrigerant
Voltage is now applied at all times from Circuit
pressure. The switch opens just above the
Breaker #24 through the now closed contacts of freezing point, providing system freeze protection.
Blower Relay to the coil of A/C Condenser Fan The temperature switch closes as the evaporator
Relay. The coil is then grounded through the A/C
temperature rises, allowing the Condenser Fan to
Refrigerant Pressure Cutoff Switch through the
run, maintaining system cooling.
Control Assembly, which is case grounded. The A/C
Pressure Cutoff Switch will close when the A/C Evaporator Temperature Sensor
system pressure is within specifications. When this The Evaporator Temperature Sensor provides
switch closes, a ground path is provided for the A/C
additional protection from icing conditions in the
Condenser Fan Relay, and the relay contacts will
evaporator core by sensing the evaporator core
close. Voltage is now applied from the Circuit
temperature and removing ground from the
Breaker #20 through the closed contacts of A/C
compressor relay coil when the temperature falls
Condenser Fan Relay to the A/C Condenser Fan
below a set value.
Motor. Since the A/C Condenser Fan Motor is
permanently grounded at G107, the fan will run.
1998 -
MO-lsuzu
1-176 HVAC Systems with A/C-Manual HVAC
J4245 J 33940-A
External Snap Ring Pliers Puller Installer
671 247636
J8433 J 33943-A
Compressor Pulley Puller Pulley Puller Pilot
216164 247641
J8092 J 33942-B
Driver Handle Seal Seat Removal/Installer
2015 247668
J 33939 (TO J 33944-4

Armature Holder Puller Forcing Screw
247673 247669
1998 -
MD-lsuzu
Manual 1-177
J 33994-A J 39400
Armature Plate Remover Electronic Leak Detector
247670 3547
J 39500-A
J 34614 Refrigerant, Recovery,
Shaft Seal Protector Recycling and Recharging
Station
6206 82133
J 36645
Evaporator Cleaning Gun
3550
1998 -
MD-lsuzu
Manual HVAC
BLANK
199S -
MD-lsuzu
Section 8
Body and Accessories
Lighting ...8-7 Headlamps Inoperative Left High -
Systems........................................
Beam (Headlamp)......................................8-61
Specifications............................................... ...8-7
Fastener Tightening Specifications........... Headlamps Inoperative Right High -
...8-7
Beam (Filament) ........................................8-61
Schematic and Routing Diagrams ............ ...8-7 Headlamps Inoperative Right High -
Lighting Systems Schematic References. ...8-7 Beam (Headlamp)......................................8-62

Lighting Systems Schematic ...8-7
Icons........... Headlamps Inoperative High Beams..........8-62
-
Headlights DRL Schematics ...8-8

..................... Headlamps Inoperative -
Flash to Pass .......8-63
Exterior Lights Schematics....................... .8-10 Headlamps Inoperative -
One Lamp
Backup Lights Schematics........................ .8-16
(Left)...........................................................8-63
Interior Lights Schematics......................... .8-17 Headlamps Inoperative One Lamp
-
Interior Lights Dimming Schematics .8-18

......... (Right).........................................................8-63
Component Locator..................................... .8-19 Headlamps, DRL On with Engine
Lighting Systems Components .8-19 Not Running
................. ...............................................8-64
Lighting Systems Component Views........ .8-22 High Beam Indicator
Inoperative...................8-64
Visual Identification..................................... .8-43 Instrument Panel Lamps Inoperative
Lighting Systems Connector End Views.. (Dimming Lamps Inoperative)
.8-43 ...................8-65
Diagnostic Information and Procedures .......8-50 Instrument Panel Lamps Inoperative
(Always at Full Brightness)........................8-66
DRL System
Check........................................8-50 License and Tail Lamps Inoperative
Exterior Lights System Check .......................8-50
(License and Tail Lamps)..........................8-66
Backup Lights System Check........................8-50
License and Tail Lamps Inoperative
Interior Lights System Check.........................8-50 (Left Rear Taillamp Inoperative)................8-67
Interior Lights Dimming System Check.........8-50 License and Tail Lamps Inoperative
Backup Lamps Inoperative ............................8-51 (Both Taillamps Inoperative)......................8-68
Clearance Lamps Inoperative........................8-52 Park Lamps Inoperative Front....................8-68
-
Courtesy or Dome Lamps Inoperative..........8-52 Park Lamp Inoperative LF..........................8-69

-
DRL Headlamps Always Park Lamp Inoperative RF..........................8-69

On..........................8-53
-
DRL Indicator Inoperative..............................8-53 Park, Side, and Front Marker Lamps

Dome Lamps Inoperative with LF Door Inoperative..................................................8-70
Open...........................................................8-54 Park, Side Marker, and Clearance
Hazard Lamps Inoperative.............................8-55 Lamps Always On......................................8-70
Headlamps Inoperative Left Low Beam .....8-55
-
Park, Side Marker, and Clearance
Headlamps Inoperative Right Low Beam...8-55
- Lamps Inoperative .....................................8-71
Headlamps Inoperative Low Beams - Rearview Mirror Lamps Inoperative -
(DRL Outside (Both Mirrors)...............................8-72

Off)....................................................8-56
Headlamps Inoperative Low Beams - Rearview Mirror Lamps Inoperative -
(During DRL Outside (Right Mirror)................................8-72

Operation).............................8-57
Headlamps Low Beams On with
- Rearview Mirror Lamps Inoperative -
Headlamp Switch Off (DRL Off)................8-59 Outside (Left Mirror)

..................................8-73
Headlamps Low Beams On with
-
Side Marker Lamp Inoperative -
Headlamp Switch Off One Lamp (Left) ........................................8-73

(During DRL Side Marker Lamp Inoperative -
Operation).............................8-60
Headlamps Inoperative Left High Beam - One Lamp (Right)......................................8-74
(Filament) Side Marker Lamps Inoperative
...................................................8-61 ....................8-75
1998 -
MO-lsuzu
8-2 Table of Contents Body and Accessories
Stop Lamps Always On (Air Brakes) Wipers/Washer Systems............................. 8-103
...........8-77
Stop Lamps Always On Schematic and Routing Diagrams............... 8-103
(Hydraulic
Brakes)..................................... 8-77 Wiper/Washer System Schematic
Stop Lamps Inoperative All (Air Brakes) ...8-78
References.............................................. 8-103
-
Stop Lamps Inoperative All -
Wiper/Washer System (Pulse)

(Hydraulic 8-79
Brakes)..................................... Schematics.............................................. 8-104
Stop Lamps Inoperative One -
Component Locator....................................... 8-105

(Left 8-80
Rear)................................................ Wiper/Washer System Components........... 8-105
Stop Lamps Inoperative One -
Wiper/Washer System Component

(Right 8-81
Rear)............................................... 8-106
Views.......................................................
Turn Signal Lamps Inoperative Front........
-
8-81
Visual Identification....................................... 8-108
Turn Signal Lamp Inoperative -
LF.............. 8-82 Wiper/Washer System Connector

Turn Signal Lamp Inoperative RF.............. 8-83
-
End 8-108
Views...............................................
Turn Signal Lamps and Indicators Inop -
Diagnostic Information and Procedures..... 8-109

Front........................................................... 8-85 Wiper/Washer Diagnostic System Check... 8-109
Turn Signal Lamps Inoperative Rear......... 8-85
-
Wipers All Modes and Washer

Turn Signal Lamps Inoperative LR............ 8-86
Inoperative............................................... 8-109
-
Turn Signal Lamp Inoperative RR

-
Wipers All Modes Inoperative......................8-110

.............8-86
Turn Signal Indicators Inoperative................ 8-87 Wipers High Mode Inoperative, Low
Turn Signal Indicators Inoperative Left......8-88
-
Mode Operates ........................................8-111
Turn Signal Indicators Inoperative Right.... 8-88
-
Wipers Low Mode Inoperative, High
Turn Signal Lamps Inop LH Output
- Mode Operates......................................... 8-111
at Trailer Conn 8-89 Wipers Always On........................................8-112
..........................................
Turn Signal Lamps Inop RH Output
-
Washers Inoperative.....................................8-113
at Trailer Conn Washers Always On.....................................8-113
..........................................8-90
Repair Instructions.......................................... 8-91 Wiper Arm Tip Pressure Check,
Headlamp Replacement................................ 8-91 Blade Element
Check..............................8-114
Headlamp Aiming.......................................... 8-93 Repair Instructions.........................................8-114
Marker Lamp Replacement Side -
Washer Pump/Reservoir Replacement........8-114
(Housing)................................................... 8-93 Wiper Arm Replacement..............................8-116
Park/Turn Signal Lamp Replacemen Wiper Arm Blade Replacement...................8-116
(Housing)................................................... 8-94 Wiper Center Pivot Replacement................8-117
Clearance Lamp Replacement Wiper Motor Replacement ...........................8-118
(Lamp Housing)......................................... 8-94
Wiper Transmission Replacement...............8-119
DRL Relay Replacement............................... 8-95
Wiper Chatter Repair.................................. 8-120
IP Lamp
Replacement................................... 8-96 Wipers/Washer Switch Replacement.......... 8-120
Dome Lamp Replacement (Housing)........... 8-96
Description and Operation ........................... 8-121
Tail Lamp Replacement 8-97
(Bulb)...................... Windshield Wipers/Washer System
Tail Lamp Replacement (Housing)................ 8-98
Description............................................... 8-121
Clearance Lamp Replacement -
Wiper/Washer System Operation................ 8-121

Outside Mirror (Housing)........................... 8-99
Wiper/Washer System Circuit
Description and Operation ...........................8-100
Lighting System Description........................ 8-100 Description............................................... 8-121
DRL Circuit Description............................... 8-100 Entertainment.................................................. 8-123

Schematic and Routing Diagrams............... 8-123
Exterior Lights Circuit Description
Entertainment Schematic References......... 8-123
(Stop Lamp Circuit Operation)................ 8-100
Backup Lights Circuit Description............... 8-101 Entertainment Schematic Icons.................. 8-123
Radio/Audio System Schematics................ 8-124
Interior Lights Circuit Description................ 8-101
Interior Lights Dimming Circuit
8-101 Entertainment Components......................... 8-125
Description...............................................
Special Tools and Equipment...................... 8-102 Entertainment Component Views................ 8-126
Special 8-102 Entertainment Connector End Views.......... 8-128
Tools................................................
(995 -
MD-ISUZU
Body and Accessories Table of Contents 8-3
Diagnostic Information and Testing for Short to

Ground.........................8-165
Procedures..................................................8-129 Testing for Electrical Intermittents
...............8-166
Radio Always On Testing for Poor
.........................................8-129 Connections......................8-166
Radio Memory Inoperative...........................8-129 Wiring
Repairs..............................................8-167
Radio Display Inoperative, No Sound Splicing Inline Harness
Diodes....................8-172
from Speakers..........................................8-129 H02S Wiring Repairs...................................8-173
Tape Player Inoperative...............................8-130 Connector Repairs
.......................................8-173
Speaker Noise General.............................8-130
-
Connector Position Assurance Locks..........8-174

Antenna Diagnostic Check...........................8-133 Terminal Position Assurance Locks.............8-174
Speakers Inoperative One or More
-
Schematic and Routing Diagrams...............8-175

(Left Front Speaker)
................................8-134 Power and Grounding Schematic
Speakers Inoperative One or More
-
(Right Front Speaker)..............................8-136 References...............................................8-175

Power and Grounding Schematic Icons .....8-175
Repair Instructions.........................................8-137
Power Distribution Schematics....................8-176
Radio Replacement......................................8-137
Fuse Block Details Schematics...................8-180
Cleaning Tape Head and Capstan,
Ground Distribution Schematics
Cassette Cleaning....................................8-138
(Battery and Body
Fixed Antenna Mast Replacement..............8-139 Grounds)...................8-190
Upfitter Provision
Schematics......................8-203
Speaker Replacement..................................8-140
Component Locator........................................8-204
Description and Operation............................8-141
Power and Grounding Components............8-204
Radio/Audio System Description .................8-141
Power and Grounding Component
Radio/Audio System Operation....................8-141
Views........................................................8-218
Radio/Audio System Circuit Description......8-142
Power and Grounding Connector End
Wiring Systems...............................................8-143 Views........................................................8-221
Specifications..................................................8-143 Diagnostic Information and Procedures .....8-222
Fastener Tightening Specifications..............8-143 Upfitter Provision System
Check.................8-222
Diagnostic Information and Procedures .....8-143 Cigar Lighter/Auxiliary Outlets System
Where to Find Electrical Schematics..........8-143 Check.......................................................8-222
How to Use Electrical Diagnosis.................8-146 Cigar Lighter Inoperative
.............................8-223
How to Use Electrical Schematics ..............8-146 Upfitter Provision Relay Inoperative............8-223
How to Use Schematic Reference Schematic and Routing Diagrams ...............8-224

Data Link Connector Schematic
Tables.......................................................8-147
How to Use Schematic Icon Tables............8-147 References...............................................8-224
How to Use Component Location Tables ...8-147 Data Link Connector Schematic Icons........8-224
How to Use Component Location Views ....8-148 Data Link Connector Schematics................8-225
How to Use Connector End Views.............8-149 Component Locator........................................8-226
How to Use Diagnostic System Checks .....8-149 Data Link Connector Components..............8-226
How to Use Diagnostic Tables....................8-150 Data Link Connector Component Views..... 8-226
How to Use Circuit Descriptions..................8-151 Visual Identification........................................8-227
Electrical Symbols ........................................8-151 Data Link Connector End Views.................8-227
General Electrical Diagnosis Procedures....8-156 Diagnostic Information and Procedures .....8-227
Strategy Based Diagnostic Flow .................8-160 Data Link Connector System Check...........8-227
Symptom Diagnostic Example.....................8-161 Scan Tool Does Not Communicate with
Checking Aftermarket Accessories..............8-162 Components (EBCM (Hydraulic))............8-227
Scan Tool Does Not Communicate with
Troubleshooting with a Test Light ...............8-162
Components (EBCM (Air)).......................8-228
Troubleshooting with a Digital Multimeter ...8-163
Description and Operation............................8-229
Troubleshooting with a Short Finder...........8-163
Data Link Connector Description.................8-229
Using Connector Test Adapters...................8-163
Data Link Connector Operation...................8-229
Using Fused Jumper Wires.........................8-163
Data Link Connector Circuit Description.....8-229
Testing for Voltage
.......................................8-164 Inline Harness Connector End Views .........8-230
Testing for Continuity
...................................8-164 Harness Routing Views................................8-258
1998 -
MD-lsuzu
Instrument Panel, Gauges Indicator Low Engine Coolant

-
and Console................................................ 8-283 Inoperative (Cell 81)............................... 8-326

Speedometer Inaccurate
Specifications................................................. 8-283 (J 38522 Unavailable)............................. 8-327
Fastener Tightening Specifications............. 8-283
Speedometer and/or Odometer
Schematic and Routing Diagrams............... 8-283
Inoperative............................................... 8-327
Instrument Cluster Schematic
Tachometer Inoperative............................... 8-328
References............................................... 8-283 Schematic and Routing Diagrams............... 8-328
Instrument Cluster Schematic Icons........... 8-283
Audible Warnings Schematic References.. 8-328
Instrument Cluster: Analog Schematics...... 8-284
Audible Warnings Schematics..................... 8-329
Instrument Cluster Components 8-291
................. Audible Warnings Components................... 8-330
Instrument Cluster Component Views........ 8-292
Audible Warnings Component Views 8-331
Visual Identification....................................... 8-303 .........
Audible Warnings Connector End Views.... 8-333
Instrument Cluster Connector End Views.. 8-303
Audible Warnings Diagnostic System
Diagnostic Information and Procedures..... 8-309 8-334
Gauge Engine Coolant Temp
-
Check.......................................................
Chime Always 8-334
Always Cold............................................. 8-309 On........................................
Chime Inoperative....................................... 8-335
Gauge Eng Coolant Temp Inaccurate
-
Fasten Safety Belt Chime Always On........ 8-336

or Inoperative.......................................... 8-310
Repair Instructions........................................ 8-337
Gauge Engine Oil Pressure Always
-
IP Cluster Replacement
High...........................................................8-311
Gauge Engine Oil Pressure
-
(Instrument Cluster)................................. 8-337
IP Cluster Replacement (Speedometer)..... 8-338
Always
Low............................................. 8-312
Gauge Eng Oil Pressure Inaccurate or Cigar Lighter 8-339
-
Replacement.........................
Inoperative............................................... 8-313 Engine Oil Pressure Switch
Gauge Fuel Always Indicates Empty
-
Replacement............................................ 8-339
(Single Tank) IP Carrier
...........................................8-313 Replacement............................... 8-340
Gauge Fuel Always Indicates Empty
-
Multifunction Alarm Module
(Dual
Tanks)............................................ 8-314 Replacement............................................ 8-345
Gauge Fuel Always Indicates Full
-
(Single Tank) Instrument Cluster Circuit Description........ 8-346
...........................................8-315
Gauge Fuel Always Indicates Full
-
Audible Warnings Operation....................... 8-347

(Dual
Tanks)............................................ 8-316 Audible Warnings Circuit Description 8-350
.........
Gauge Fuel Inaccurate or Inoperative
-
8-351
(Single Tank) Horns..................................................................
...........................................8-317 8-351
-
Specifications.................................................
(Dual 8-318 Fastener Tightening Specifications............. 8-351
Tanks)............................................
- Schematic and Routing Diagrams............... 8-351
(Vehicle Runs Out at Half Horns Schematic References 8-351
Tank)............ 8-320 .....................
Gauges Inoperative All............................. 8-321
-
Horns Schematics....................................... 8-352
Gauge Voltmeter Inaccurate or
-
Inoperative...............................................
8-322 Horns Components...................................... 8-353
Indicator Check Gauge Always On
-
Horns Component Views 8-353

(Cell ............................
81)...................................................
8-322 Horns Connector End Views....................... 8-357
Indicator Check Gauge Always On
-

(Cell
41)................................................... 8-323 Horns Inoperative (Both Do Not Sound)....8-357
Indicator Check Gauge Inoperative
-
8-323
......... Horns Inoperative (One Does
Indicator Fasten Safety Belt Not
Sound).............................................. 8-358
-
Always On............................................... 8-324

Horns Always On ........................................8-358
Indicator Fasten Safety Belt
-

Inoperative............................................... 8-324 Horn Replacement (Single)......................... 8-359
Indicator Low Engine Coolant
-
8-325 Horn Replacement (Dual)........................... 8-360

Always
On...............................................
Indicator Low Engine Coolant
-
Inoperative (Cell 41)................................ 8-325 Horns Circuit Description 8-360
............................
1998 -
MD-lsuzu
Body and Accessories Table of Contents 8-5
Exterior Trim....................................................8-361 Wheelhouse Panel Replacement

Repair Instructions.........................................8-361 (Lower).....................................................8-397
Emblem/Nameplate Replacement................8-361 Wheelhouse Panel Replacement
Grille (Upper).....................................................8-398
Replacement.......................................8-361
Washing and Waxing...................................8-362 Doors..................................................................8-399
Foreign Material Deposit Removal Specifications..................................................8-399
..............8-362
Cleaning Bright Metal Fastener Tightening Specifications..............8-399
Parts.........................8-362
Schematic and Routing Diagrams...............8-399
Waterleaks.........................................................8-363 Power Door Systems Schematic
Diagnostic Information and Procedures .....8-363
Waterleak Test Preparation..........................8-363 References...............................................8-399
Power Windows Schematics........................8-400
Repair Instructions.........................................8-363 Outside Mirrors Schematics.........................8-401
Generalized Testing......................................8-363
Component Locator........................................ 8-402
Diagnostic Information and Procedures .....8-364
Power Door Systems Components.............8-402
Water Hose Test...........................................8-364
Power Door Systems Component
Air Hose
Test................................................8-364 Views........................................................8-403
Stationary Window Waterleak Repair..........8-364 Power Door Systems Connector End
Stationary Windows ......................................8-365 Views........................................................8-406
Repair Instructions.........................................8-365 Diagnostic Information and Procedures .....8-407
Windshield Upper Reveal Molding Power Windows System Check ..................8-407
Replacement............................................8-365 Heated Mirror System Check......................8-407
Windshield Replacement..............................8-366 Power Window Inoperative RF.................8-407
-
Quarter Window Replacement.....................8-368 Power Windows Inoperative From

Rear Window Replacement.........................8-369 LF
Switch.................................................8-409
Window Polishing .........................................8-371 Heated Mirrors Inoperative
(Switch
Special Tools and Equipment.......................8-372 Indicator).................................... 8-411
Special Heated Mirrors Inoperative (Both Mirrors) ..8-411
Tools................................................8-372
Heated Mirrors Inoperative
Bumpers............................................................8-373 (LH or RH Not
Both)................................8-412
Specifications..................................................8-373 Heated Mirrors Always On ..........................8-412
Fastener Tightening Specifications..............8-373
Repair Instructions.........................................8-413
Repair Instructions.........................................8-373 Trim Panel Replacement Door .................8-413
-
Bumper Replacement -
Front......................8-373 Door Replacement .......................................8-414

Body Front End..............................................8-377 Door Handle Replacement Outside..........8-415-
Specifications..................................................8-377 Door Handle Replacement Inside.............8-417

-
Fastener Tightening Specifications..............8-377 Lock Replacement -
Door............................8-418
Repair Instructions.........................................8-378 Lock Cylinder Replacement Door.............8-420
-
Hood Replacement.......................................8-378 Striker Replacement -
Door.........................8-420
Hood Latch Replacement............................8-378 Window Regulator Replacement
Fender Replacement Front.......................8-381
-
(Right
Side)..............................................8-421
Battery Box Replacement............................8-383 Window Regulator Replacement
Component Box Replacement.....................8-384 (Left
Side)................................................8-422
Cab Replacement.........................................8-385 Window Handle Replacement .....................8-422
Cab Lock Replacement................................8-388 Window Replacement Door......................8-423
-
Cab Tilt Support Replacement ....................8-391 Window Run Channel Replacement ...........8-424
Step and Support Replacement Upper ....8-392 -
Window Replacement Inner Lower...........8-425
-
Fender Extension Bracket Window Replacement Outer Lower..........8-426

-
Replacement -
Front................................8-394 Mirror Replacement...................................... 8-427

Air Scoop Replacement...............................8-395 Description and Operation............................8-429
Panel Replacement Front Side.................8-396
-
Power Windows Circuit Description ............8-429

Splash Shield Replacement -
Heated Mirror Circuit Description ................8-429

Condenser................................................8-396 Special Tools and Equipment.......................8-430
Special
Tools................................................8-430
1998 -
MD-lsuzu
Seats...................................................................
8-431 Paint/Coatings................................................. 8-455
Specifications................................................. 8-431 Specifications................................................. 8-455
Fastener Tightening Specifications............. 8-431 Clearcoat Repair Specifications -
3M
Diagnostic Information and Procedures..... 8-431 Products............................................ 8-455
Seat Manual Adjuster Does
- Clearcoat Repair Specifications -
Not 8-431 Meguiar Products.................................... 8-456

Unlock...............................................
Seat -
Manual Adjuster Between Basecoat/Clearcoat Paint Systems............. 8-457
Lock
Positions.........................................
8-431 Anti-Corrosion Treatment and Repair......... 8-457
Seat Manual Adjuster Does Not Lock.....8-431
-
Paint Identification....................................... 8-459
Repair Instructions........................................ 8-432 Repair Instructions........................................ 8-460
Seat Replacement....................................... 8-432 Clearcoat Repair w/o Repainting................ 8-460
Seat Replacement Center........................ 8-433
-
Corrosion Repair......................................... 8-461
Seat Riser Replacement (Passenger)........ 8-434 Environmental Fallout (Acid Rain).............. 8-461
Seat Riser Replacement (Driver)................ 8-438 Paint 8-462
Gauges...............................................
Interior Trim..................................................... 8-441 Clearcoat Thickness.................................... 8-462
Repair Instructions........................................ 8-441 Rail Dust Damage 8-462
Repair...........................
Mat/Carpet Replacement Front Floor....... 8-441
-
Frame and Underbody................................ 8-463
Trim Panel Replacement -
Cargo Specifications................................................. 8-463
Area Rear................................................ 8-442 Fastener Tightening Specifications............. 8-463
Door Sill Plate Replacement....................... 8-442 Yield Strength of Different 8-463
Metals...............
Headliner Replacement............................... 8-443 Welding 8-463
Table..............................................
Console Replacement Overhead .............
-
8-444 Electrode Table........................................... 8-463
Sunshade Replacement.............................. 8-446 Plug Weld 8-464
Chart..........................................
Garnish Molding Replacement -

Windshield
Pillar...................................... 8-446 Checking Frame
Alignment......................... 8-464
Garnish Molding Replacement Side -
8-465
Door Upper (On Roof Panel)................. 8-447 Frame...........................................................
Frame Conditions........................................ 8-466
Garnish Molding Replacement Side -

Door Upper (On Body)............................ 8-447
Molding Replacement Rear Window -
Frame Straightening Description................. 8-467
8-448 Frame Repair............................................... 8-468
Upper.......................................................
Trim Panel Replacement Rear Quarter...
-
8-449 Crossmember Replacement........................ 8-473

Cleaning Vinyl Trim 8-450 Body Mount Replacement (Cab Mounts)... 8-473
..................................... Body Mount Replacement (Cab Mount).....
Spot Cleaning Fabric 8-450 8-477
Trim..........................
Cleaning Agents.......................................... 8-450 Body Mount Replacement (Bracket)........... 8-479
Interior 8-451 Tow Hook Replacement.............................. 8-480
Cleaning..........................................
Basic Steps Before Cleaning...................... 8-451 Assist Step and Support Replacement -
8-481
Cleaning Glass 8-451 Lower.......................................................
Surfaces.............................
Removal of Specific Stains......................... 8-451
Welding
Seat Belt Description..................................... 8-483
Care............................................. 8-452 Frame and Underbody Description............. 8-483
Plastic Panel Information and Repair...8-453
Minimizing Frame Service Description 8-484
Repair Instructions........................................ 8-453 .......
Flexible Plastic Part Refinishing
Collision Repair............................................. 8-485
.................
8-453
1998 -
MD-lsuzu
Body and Accessories Lighting Systems 8-7
Lighting Systems
Specifications

Specification
Headlamp Bezel Screws 1.9N.m 17 Ib in
Park/Turn Signal Lamp Retaining Nut 8N.m 71 Ib in
Tail Lamp Retaining Bolts 35N.m 26lbft
Lighting Systems Schematic References
Reference on Schematic Section Number -

Subsection Name
Audible Warnings Cell 76 8Instrument Panel, Gauges and Console
Exterior Lamps Cell 110 8Lighting Systems

Heated Mirrors Cell 61 8Doors
Horns Cell 40 8Horns
Interior Lamps: Dimming Cell 117 8Lighting Systems
Park Lamp Relay Cell 110 8Lighting Systems
Power Distribution Cell 10 8Wiring Systems
Lighting Systems Schematic Icons

Refer to ESD Notice in Cautions and Notices.
Â 19384
1998 -
MO-lsuzu
8-8 Lighting Systems Body and Accessories
1998 -
MD-lsuzu
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MO-lsuzu
Component Locator
Lighting Systems Components

Component Location Locator View Connector End View
Automatic Transmission Lighting Systems Lighting Systems
(AT) Neutral Signal Component Views Connector End Views
Under the right seat
Driver Module
(Cat Diesel)
Automatic Transmission Lighting Systems
In the center console
(AT) Selector Control Connector End Views

Automatic Transmission Lighting Systems
In the center console, a part of the
(AT) Shift Indicator Lamp
Connector End Views

automatic transmission (AT) selector control
(Console Mounted)
On the rear of the left frame rail (part of Lighting Systems Lighting Systems
Backup, Lamp Left Side
the tail, stop and turn signal lamp) Component Views Connector End Views
Backup Lamp, On the rear of the right frame rail (part of Lighting Systems Lighting Systems
Right Side the tail, stop and turn signal lamp) Component Views Connector End Views
Backup Lamps Switch Lighting Systems Lighting Systems
On the lower right side of the transmission
(Automatic Transmission) Component Views Connector End Views
(Cat Diesel and 5 or Component Views Connector End Views
On the upper right side of the transmission
6 Speed Manual
Transmission)

(Cat Diesel and 9 or Component Views Connector End Views
On the upper right side of the transmission
10 Speed Manual
Transmission)
In the center of the IP, at the right of the Lighting Systems Lighting Systems
Cigar Lighter Lamp
radio (part of the cigar lighter) Component Views Connector End Views
Clearance Lamp, At the top of the roof, on the forward left Lighting Systems Lighting Systems
Left Side outboard side of the cab Component Views Connector End Views
Clearance Lamp, On the top of the roof, on the forward right Lighting Systems Lighting Systems
Right Side exterior side of the cab, outboard Component Views Connector End Views
In the right top of the IP, under the access Lighting Systems
Clearance Lamps Relay

Lighting Systems Lighting Systems
Clearance Lamps Switch In the center of the IP
On the right side of the lower IP, in front of Lighting Systems
Daytime Running Lamps
the blower motor, behind the panel, in the
Connector End Views
(DRL) "Off" Relay
relay center 3
On the right side of the lower IP, in front of Lighting Systems

Daytime Running Lamps
the blower motor, behind the panel, in the
Connector End Views
(DRL) "On" Relay
relay center 3
Daytime Running Lamps At the main branch of the data link Lighting Systems

(DRL) Resistor connector (DLC) breakout Connector End Views
Dome and Lighting Systems

At the center front of the cab at the top
Reading Lamp Component Views

Dome and Reading In the center front top of the cab (part of Lighting Systems

Lamp Switch the dome and reading lamp) Component Views

Door Jamb Switch, On the left front door frame, at the rear of Lighting Systems

Left Side the opening Component Views

Headlamp, Left Lighting Systems Lighting Systems
In the left front of the exterior cab body
High Beam Component Views Connector End Views
Headlamp, Left High/ In the left front of the exterior cab body
Low Beam Component Views Connector End Views
1998 -
MD-lsuzu
Lighting Systems Components (cont'd)

Headlamp, Right Lighting Systems Lighting Systems
In the right front of the exterior cab body
High Beam Component Views Connector End Views
Headlamp, Right Lighting Systems Lighting Systems

In the right front of the exterior cab body
High/Low Beam Component Views Connector End Views
Headlamps In the right top of the IP, under the access Lighting Systems

Dimmer Relay panel, in relay center 1 Component Views

Headlamps On the left side of the lower steering Lighting Systems

Dimmer Switch column Component Views

On the left side of the steering column Lighting Systems
Headlamps Switch
(part of the multifunction switch) Component Views

On the top of the roof, in the center of the Lighting Systems Lighting Systems
ID Lamp, Center
cab Component Views Connector End Views
On the top of the roof, in the forward left Lighting Systems Lighting Systems
ID Lamp, Left Side
inboard side of the cab Component Views Connector End Views
On the top of the roof, in the forward right Lighting Systems Lighting Systems
ID Lamp, Right Side
inboard side of the cab Component Views Connector End Views
In the upper IP harness, under the crash
Interior Lamps pad, at the top of the IP, joint connector 1,
Dimming Buss row 1 (terminals 1A, 1B, 1C, 1D, 1E, 1F,
1G,1H, 1J and 1L)
Inverting Driver Module Lighting Systems Lighting Systems
(ABS-Hydraulic) Component Views Connector End Views
In the IP, on the lower right side of the Lighting Systems
IP Lamps Dimmer
speedometer, part of the instrument panel Component Views
Control
cluster (I PC)
At the rear of the right frame rail, part of Lighting Systems Lighting Systems
License Lamp
the right taillamp Component Views Connector End Views
Lighted Mirror Connector In connector C216 (6 cavities), in the upper Lighting Systems

Jumper IP harness Connector End Views

Lighted Outside Left Lighting Systems
On the exterior of the left door
Rearview Mirror Component Views

Lighted Outside Right Lighting Systems
On the exterior of the right door
Rearview Mirror Component Views

In the top of the IP, under the access Lighting Systems
Lighting Relay

Marker Lamps Relay

Marker Lamps Switch In the center of the IP
Neutral and Backup
Lamps Switch Internal to the automatic electronic

(Push-Button Shift transmission

Control)
Park Brake Switch Lighting Systems Lighting Systems

On the park brake lever bracket
(Hydraulic Brakes) Component Views Connector End Views
Park/Turn Signal Lamp, Lighting Systems Lighting Systems
On the left front of the front bumper
Left Front Component Views Connector End Views
Park/Turn Signal Lamp, Lighting Systems Lighting Systems
On the right front of the front bumper
Right Front Component Views Connector End Views
PRNDL Lamp Lighting Systems
In the center console, part of the automatic
(Console-Mounted
Connector End Views

transmission (AT) selector control
Selector)
1998 -
MD-ISUZU
Lighting Systems Components (cont'd)

Sidemarker Lamp, Lighting Systems Lighting Systems
In the left forward bottom of the door
Left Front Component Views Connector End Views
Sidemarker Lamp, Lighting Systems Lighting Systems
In the right forward bottom of the door
Right Front Component Views Connector End Views
Stoplamps Relay In the center of the lower IP, behind the Lighting Systems

(ABS-Hydraulic) panel, in relay center 2 Component Views

On the left side of the exterior bulkhead, Lighting Systems Lighting Systems
Stoplamps Switch
(ABS-Air)
under the brake pedal, on the air brake Component Views Connector End Views
application valve
Stoplamps Switch
On the Brake Pedal Support
(ABS-Hydraulic)
Stoplamps Switch 1
(ABS-Air) under the brake pedal, on the air brake Component Views Connector End Views
application valve
Stoplamps Switch 2
under the brake pedal, on the air brake Component Views Connector End Views
(ABS-Air)
application valve
Tail and Stop/Turn Signal Lighting Systems Lighting Systems

On the rear of the left frame rail
Lamp, Left Side Component Views Connector End Views
Tail and Stop/Turn Signal Lighting Systems Lighting Systems
On the rear of the right frame rail
Lamp, Right Side Component Views Connector End Views
Taillamps Relay
panel, in the relay center 1 Component Views

In the side of the cab bridge, on the Lighting Systems Lighting Systems
Tractor Receptacle
bracket near the power steering reservoir Component Views Connector End Views
Behind the cab, on the cab bridge bracket Lighting Systems Lighting Systems
Trailer Receptacle
at the left frame rail Component Views Connector End Views
In the left side of the cab bridge, on the Lighting Systems Lighting Systems
Trailer Stop Relay (Cat
relay bracket on the front of the electronic Component Views Connector End Views
Diesel and ABS-Air)
brake control module (EBCM)
Trailer Stop Relay (Cat In the left side of the cab bridge, on the Lighting Systems Lighting Systems
Diesel and relay bracket on the power steering Component Views Connector End Views
ABS-Hydraulic) reservoir mounting bracket
Trailer Stop Relay In the left side of the cab bridge, on the Lighting Systems Lighting Systems
(Gasoline and relay bracket on the power steering Component Views Connector End Views
ABS-Hydraulic) reservoir mounting bracket
Trailer Stoplamps Switch Lighting Systems

In the center of the IP, below the radio
(ABS-Air) Component Views

On the left side of the steering column Lighting Systems
Turn Signal Switch

Turn/Hazard Flasher Under the center of the IP, at the floor Lighting Systems Lighting Systems
Module level Component Views Connector End Views
Turn/Trailer Relay, In the right top of the IP, under the access Lighting Systems

Left Side panel, in relay center 1 Component Views

Turn/Trailer Relay, In the right top of the IP, under the access Lighting Systems

Right Side panel, in relay center 1 Component Views
199B
MD-lsuzu
Lighting Systems Component Views
Instrument Panel Harness to Right Seat
228430
Legend
(1) C215 (2 Cavities) (7) Park Brake Control Module
(2) Lower IP Harness (8) Vehicle Speed Sensor (VSS) Buffer
(3) Automatic Transmission Neutral Signal (9) Powertrain Control Module (PCM)
Driver Module (Cat Diesel) (Gasoline)
(4) Inverting Driver Module Connector (10) PCM Connector C2 (24 Cavities)
(5) Inverting Driver Module (ABS-Hydraulic) (11) PCM Connector C1 (32 Cavities)
(6) Multifunction Alarm Module
(995 -
MD-lsuzu
Rear Chassis Harness and Taillamps, Upper Left Rear View
231737
Legend
(1) Right Tail, Stop and Turn Signal Lamp with (2) Left Tail, Stop and Turn Signal Lamp with
Backup Lamp Backup Lamp
1998 -
MD-lsuzu
>4 Lighting Systems Body and Accessories
Automatic Transmission Harness (Cat Diesel and Automatic Transmission)

Upper Left Rear View
228477
gend
(1) Backup Lamps Switch Connector (4) Automatic Transmission Modulator
(2) Vehicle Speed Sensor (VSS) (5) Neutral Switch
(3) Backup Lamps Switch (6) Neutral Switch Connector
1998 -
MD-lsuzu
Manual Transmission Harness (5 or 6-Speed), Upper Left Rear View
231718
Legend
(1) Backup Lamps Switch (3) VSS (ABS-Air)
(2) Vehicle Speed Sensor (VSS)
(Hydraulic Brakes)
1998 -
MD-lsuzu
Manual Transmission Harness (9 or 10-Speed), Upper Left Rear View
231666
Legend
(1) Backup Lamps Switch (2) Vehicle Speed Sensor (VSS)
1998 -
MD-lsuzu
231675
Legend
(4) Cigar Lighter
1998 -
MD-lsuzu
Roof-Top Lamps (Front View)
231439
Legend
(1) Left and Right Clearance Lamps and
ID Lamps
1998 -
MD-lsuzu
Instrument Panel, Right Side Forward View
228475
Legend
(1) Relay Center 1 (2) IP Fuse Block
1998 -
MD-lsuzu
Instrument Panel Switches, Center Forward View
231678
Legend
(1) Exhaust Brake Switch (5) Air Suspension Dump Switch
(2) Fast Idle Switch (6) Differential Lock Switch
(3) Heated Mirror Switch (7) Clearance Lamps Switch
(4) Two Speed Rear Axle Shift Switch
(Automatic Transmission)
1998 -
MO-lsuzu
Interior Roof, Right Upper View
231693
Legend
(1) Dome and Reading Lamp (2) Dome and Reading Lamp Switch
7998 -
MD-lsuzu
Door Jamb, Left Rear View
231695
Legend
(1) Left Door Jamb Switch
1998 -
MD-lsuzu
Forward Lamps, Right Front View
231423
Legend
(1) Right High/Low Beam Headlamp (3) Right Front Side Marker Lamp (Left Similar)
(Left Similar)
(2) Right High Beam Headlamp (Left Similar)
1998 -
MD-lsuzu
Steering Column, Left View
228426
Legend
(1) Multifunction Switch (3) Ignition Switch
(2) Right Multifunction Lever (4) Left Multifunction Lever
1998 -
MD-ISUZU
Mirror (Right)
231453
Legend
(1) Right Lighted Mirror (Heated Mirror similar)
1998 -
MD-lsuzu
Park Brake
231691
Legend
(1) Park Brake Lever (2) Park Brake Switch (Hydraulic Brakes)
1998 -
MD-lsuzu
Turn Signal Harness (Left Front View)
231459
Legend
(1) High A-Note Horn (Single Electric Horn) (3) Left Front Park and Turn Signal Lamp
(2) Left Front Park and Turn Signal Lamp Connector
1998 -
MD-lsuzu
231681
Legend
(1) Relay Center 2 (2) Turn/Hazard Flasher Module
1998 -
MD-lsuzu
Air Brake Application Valve
231533
Legend
(1) Stoplamps Switch (2) Air Brake Application Valve
1998 -
MD-lsuzu
Trailer Front Harness to Cab Bridge, Left Forward View
231704
Legend
(1) Trailer Receptacle
1998 -
MD-ISUZU
228373
Legend
(1) ABS Relay (ABS-Air) (4) Trailer Stop Relay (Cat Diesel
(2) Front Chassis Harness and ABS-Air)
(3) Starter Relay (Cat Diesel and ABS-Air) (5) Automatic Transmission Modulator Shift
Relay (Cat Diesel)
1998 -
MD-lsuzu
Front Chassis Harness to Cab Bridge (ABS-Hydraulic) Left Forward View
228382
Legend
(1) Park Brake Pump Motor Relay (4) Starter relay (Gasoline) or Trailer Stop
(2) Power Brake Booster Pump Motor Relay Relay (Cat Diesel and ABS-Hydraulic)
(3) Starter Relay (Cat Diesel and (5) Automatic Transmission Modulator Shift
ABS-Hydraulic) Relay (Cat Diesel)
1998 -
MD-lsuzu
Visual Identification Automatic Transmission Selector Control

(AT Trans.)
Lighting Systems Connector End Views
ABS Trailer Stop Relay (Air Brakes)
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237082
Conn ector Part 6\ft/ay F
Info rmation (BL K)

39670
Circuit

12129716
Connector Part Pin Wire Color No. Function

ASM 4F M/P 280 FLX LK
Information A RED/GRN 41 Illumination
SLD (GRY)
B RED 37 Fuse Output Ignition
Circuit
Pin Wire Color No. Function Transmission
C BLK/WHT 40
Park/Neutral Signal
30 RED 142 Fuse Output Battery
Interior Lamp
85 WHT 17 Stoplamp Switch Output D BLK/RED 46
Dimming Buss
86 BLK 150 Ground
E RED/BLU 38 Select Lever Back Lamp
Q-7 IT 01 1 1
on
Backup Lamp Switch
236598
Connector Part
12052641
Information ASM 2F M/P 150 (BLK)
Circuit
A BRN 441 Fuse Output Ignition
B LTGRN 24 Back Up Lamp Feed
1998 -
MD-lsuzu
Cigar Lighter Clearance Lamps Switch
,
n=n
r A
n
l^l n
ir^r 261|
C?J 4 | 3 5
236009 237083
2 Way 6 Way
Connector Part

Connector Part
Information
Male Information
Female
Circuit Circuit
Interior Lamp 1 GRN 111 Fuse Output Battery
A BLK/REED 165
Dimming Buss 2 ORN 112 Switch Output
B BRN 163 Illumination 3 ORN 113 Switch Telltale Feed
4 BLK 114 Ground
Clearance Lamp (Typical)
5 BRN 115 Illumination
jj=L
Interior L amps
6 BLK/RED 116
Dimming Buss
Dome Lamp
f Zl B
Fr
1
J= c=LJ
CD
Connector Part
2 Way M
237091 t?^^
Information (BLK)
Circuit
240168
A BLk 8 Ground 3 Way
Connector Part
B BRN 9 Lamp Feed Information
Female
Circuit
A RED 3 Dome Lamp
B RED/YEL 2 Dome Lamp
C ORN 1 Dome Lamp
7998 -
MD-ISUZU
DRL Resistor Headlamp, High Beam (Left)
|| A ||
^ r^" N
<^-^J?
^

A C B
i
J
237053 236963
2 Way 3 Way M
Information
Female Information (BLK)
Circuit Circuit
A RED/YEL 715 Lighting Relay A
Not Used
Daytime Running Lamp B RED/YEL 688 Headlamp
B RED/BLK 729
ON Relay BLK/WHT
C 692 Headlamp High Beam
Hazard Flasher Headlamp (Left)
C
BB^BE 3
@[9]BB[e]B
r
236961
Connector Part
10 Way 236963
Information
Female 3 Way M
Connector Part
Circuit Information (BLK)
Circuit
Front Combination Pin Wire Color No. Function
1 LT BLU 136
Lamp (Left)
A BLK/WHT 690 High Beam
2 WHT 105 Stoplamp Switch (Air)
Lighting Relay
RED/BLK 691
Stoplamp S witch Output, Low
2 WHT 471
(Hydraulic)
C RED/YEL 689 Headlamp
Front Combination
3 BLU 139
Lamp, Right
4 GRN 135 Stop and Turn, Right
5 YEL 134 Stop and Turn, Left
6
Not Used
7 BLU/BLK 132 Turn Signal Input, Left
8 BLU/ORN 133 Turn Signal Input, Right
9 ORN 131 Fuse Output Battery
1998 -
MD-lsuzu
Headlamp, High Beam (Right) Inverting Driver Module
A ||
fC~^\
WBSE i)
c B
- L
Li \ .
/
}
236963 237093
3 Way M 12010488
Connector Part
Information (BLK) Connector Part 6 Way Connector
Information Assembly P/C Edgeboard
Circuit
Pin Wire Color Function Standard (BLK)
No.
A
Not Used
Circuit
B BLK/WHT 698 High Beam
Electronic Control
C A BRN 651
RED/WHT 694 Headlamp Module Pin-14
B PNK 654 Fuse Output-Battery
Head amp (Right)
Electronic Control
C WHT 653
Module P in-23
D BLK 652 Ground
A
E-F Not Used
Lighted Mirror Connector Jumper C216

G B
Li p f^\ ^
2 6 1
236963
Connector Part
Information

3 Way M
(BLK)
435
Circuit
A BLK/WHT 696 Lighting (High/Low)
236079
B RED/BLK 697 Low Beam 6
Connector Part
Way
C RED/WHT 695 Headlamp Information
Female
Circuit
2-4
Not Used
6
Not Used
1998 -
MD-ISUZU
Park Brake Switch, Daytime Running Lamps ParkfTurn Lamp, Right
(Air Brakes)
73223|
246698 12162182
Connector Part
Connector Part 2 Way M ASM 3F M/P 150.2 Series
Information
Information (GRY) Pull To Seat (BLK)
Circuit Circuit
Daytime Running Turn Signal Lamp Feed,
A DK BLU 15
A LTBLU 744 Lamps (DRL) Off Relay Right Front
Air Brake B BLK 150 Ground
Park Brake Switch C BRN 9 [Park Lamp Feed
B BLK 746
Air Brake
Side Marker Lamp (Typical)

Park/Turn Lamp, Left
d B
237053
73223
Connector Part
2 Way P
12162182
Connector Part Information . (BLK)
ASM 3F M/P 150.2 Series
Information Circuit
Pull To Seat (BLK)
Circuit
A BRN 20 Park Lamp Feed
B BLK Ground
Turn Signal Lamp Feed,
A LTBLU 14
Left Front
BLK 150 Ground
C BRN Park Lamp Feed
1998 -
MD-lsuzu
Diagnostic Information and Backup Lights System Check

Procedures Troubleshooting Hints
DRL System Check 1. Inspect the Circuit Breaker and determine the
condition. If the Circuit Breaker is Open, Locate
1. Inspect Circuit Breakers number 6, 14, 15, and and Repair the cause of the overload and
16. If the Circuit Breaker is Open, Locate and Replace the Circuit Breaker.
Repair the cause of the circuit overload and
Replace the Circuit Breaker. 2. Inspect G 404 to make certain that it is Clean
and Tight.
2. Inspect G 105 to make certain that it is clean a single lamp does not illuminate, inspect the
and tight. 3. If
lamp for an open filament. Replace the lamp if
3. Inspect the inoperative lamp for an open or required. Also inspect the lamp socket for
shorted filament. Replace the lamp if it is
corrosion. Clean the socket if required.
defective. if the
4. Adjust or replace the Backup lamp switch
4. Inspect the DRL OFF Relay, the DRL ON lamps do not turn off. Refer to Backup Lamp
Relay, the Lighting Relay, Low/High Lighting Switch replacement as appropriate.
Relay and the Panel Lamp/DRL Relay, to make
certain that they are all tightly connected. 5. Inspect for a broken (or partially broken)
conductor inside the insulation which could
5. Inspect for a broken (or partially broken) cause a malfunction but prove GOOD in a
conductor inside the insulation which could system test for continuity or voltage These
cause a malfunction but prove GOOD in a circuits may be intermittent or resistive, when
system test for continuity or voltage These loaded, and if possible, should be monitored for
circuits may be intermittent or resistive, when a voltage drop when the system is placed
loaded, and if possible, should be monitored for under load.
a voltage drop when the system is placed
under load. 6. Inspect for proper installation of aftermarket

electronic equipment which might affect the
6. Inspect for proper installation of aftermarket operation of other equipment.
operation of other equipment. Interior Lights System Check
Exterior Lights System Check Troubleshooting Hints
1. Inspect the IGNITION MaxiFuse, Circuit 1. Inspect the Circuit Breaker to determine if it is
Breakers number 11, 19, 23 (with Hydraulic Open. If the Circuit Breaker is Open, Locate
Brakes) and 25 to determine if any one of them and Repair the cause of the circuit overload
is Open. Locate and Repair the cause of the and Replace the Circuit Breaker.
circuit overload and Replace the MaxiFuse or
2. Inspect the Dome lamp Switch ground to make
Circuit Breaker(s).
certain that it is clean and tight.
2. Inspect grounds G 105, G 107, G 404, G 405 to 3. Inspect the lamp filaments to make certain that
make certain that they are Clean and Tight. they are not Open or Shorted. Replace the
3. Inspect the exterior lamps to make certain that lamp if required.
the filaments are not Open or Shorted. Replace
4. Inspect for a broken (or partially broken)
any defective lamps. conductor inside the insulation which could
4. Inspect the Instrument Cluster Left and Right cause a malfunction but prove GOOD in a
turn signal lamps to make certain that the system test for continuity or voltage These
filaments are not Open. circuits may be intermittent or resistive, when
5. Inspect for a broken (or partially broken) loaded, and if possible, should be monitored for
conductor inside the insulation which could a voltage drop when the system is placed
cause a malfunction but prove GOOD in a under load.

system test for continuity or voltage These 5. Inspect for proper installation of aftermarket
circuits may be intermittent or resistive, when electronic equipment which might affect the
loaded, and if possible, should be monitored for operation of other equipment.
a voltage drop when the system is placed
under load. Interior Lights Dimming System Check

6. Inspect for proper installation of aftermarket Troubleshooting Hints
operation of other equipment. 1. Inspect the Circuit Breaker to determine if it is
Open. Locate and Repair the cause of the
circuit overload if it is open and then Replace
the Circuit Breaker.
2. Inspect ground and make certain that it is clean
and tight.
1998 -
MD-lsuzu
3. Inspect the lamp filaments to make certain that circuits may be intermittent or resistive, when
they are not Open. Replace the lamp if any is loaded, and if possible, should be monitored for
found to be defective. a voltage drop when the system is placed
4. Inspect for a broken (or partially broken) under load.
conductor inside the insulation which could 5. Inspect for proper installation of aftermarket
cause a malfunction but prove GOOD in a electronic equipment which might affect the
system test for continuity or voltage These operation of other equipment.
Backup Lamps Inoperative

1. Place the ignition switch in RUN (Engine OFF).
1 2. Place the transmission gear select lever in
REVERSE.
Are both backup lamps inoperative? Go to Step 5 Go to Step 2
1. Remove the lens cover from the inoperative lamp.
2 2. Connect a test lamp from the center terminal of the
backup lamp socket to ground.

Did the test lamp light? Go to Step 3 Go to Step 4
Repair the open in CKT 150 (BLK) between the
3 inoperative backup lamp and ground.

Repair the open in CKT 24 (LT GRN) between Splice
4 S900 and the inoperative backup lamp?
1. Remove the lens cover from an inoperative lamp.
5 2. Connect the test lamp from the center terminal of the
backup lamp socket to ground.

Repair the open in CKT 150 (BLK) between the
6 inoperative backup lamp and ground

Connect the test lamp from terminal C at connector C402
7 to ground.
Repair the open in CKT 24 (LT GRN) between C402 and

8 the backup lamps.
1. Disconnect the backup lamp switch connector at the

transmission.
9 2. Connect the test lamp from terminal B (Automatic) or

terminal C1 (Manual) to chassis ground.

Repair the open in CKT 24 (LT GRN) between the backup
10 lamp switch C402.
Connect the test lamp from the backup lamp switch

terminal A (Automatic) or terminal C2 (Manual) to chassis
11
ground.
1998 -
MO-lsuzu
Backup Lamps Inoperative (cont'd)

Step Action Vatue(s) Yes No
Replace the backup lamp switch?

12
Connect the test lamp from connector C200 (terminal 22)

13 to ground.
Repair the open in CKT 8 or CKT 139 (PNK), or CKT 441

14 (BRN) between C200 and the backup lamp switch.
Repair the open in CKT 145 (PNK) between the IP fuse

15 block and C200.
Clearance Lamps Inoperative

Important: If some but not all of the clearance/I D
lamps are out and the bulbs have been checked,
use the schematics and DVM or the test light in
order to check suspect power circuits and ground
circuits for opens or poor connections.
Clearance Lamps Inoperative

1. Disconnect the harness connector C208.
2. Connect a test lamp between terminal E and ground
1 in the lower IP harness connector C208.
3. Set the headlamp switch to the PARK position.

Connect a test lamp between terminals E and D in the
2 lower IP harness connector C208.

Repair the open in CKT 98 (BRN) between S364 and
3 terminal E in the lower IP harness connector C208.

Repair the open in the roof harness in CKT 5 (BRN)
between S365 and terminal E in the roof harness
4 connector, or in CKT 4 (BLK) between S371 and terminal

D in the C208 roof harness connector.
Repair the open in CKT 25, CKT 22, CKT 69 or CKT 650
(BLK) between G105 and terminal D in the lower IP
5
harness connector C208.

1998 -
MD-lsuzu
Courtesy or Dome Lamps Inoperative

1. Remove the dome lamp connector.
1 2. Connect a test lamp between the dome lamp
connector terminal 1 and ground.

Replace the dome lamp assembly.
2

Locate and repair the open in CKT 1 (ORN) between the

3 dome lamp connector and the circuit breaker #7.

DRL Headlamps Always On

1. Turn the ignition switch to the RUN position.
1 2. Backprobe the DRL On relay with a test lamp from
terminal 86 to B+.
Check for a short to ground in CKT 740 (BRN) between
2 the DRL On relay and the joint connector 2.
Is there a short to ground in the circuit? Go to Step 4 Go to Step 5

Replace the DRL On relay.
3
Repair the short to ground in CKT 740 (BRN) between the

4 DRL On relay and joint connector 2.
Refer to Engine Electrical.

5
DRL Indicator Inoperative

2. Move the headlamp switch to the OFF and LO

positions.
1
3. Backprobe the instrument cluster with a test lamp

from terminal A7 to ground.
Backprobe the instrument cluster with a test lamp from
2 terminal A15 to B+.
Repair the open in CKT 1, CKT 58 or CKT 371 between

3 the IP fuse block and the instrument cluster.
Does the DRL indicator light? System OK
Repair or replace the instrument cluster.

4
Backprobe the panel lamp/DRL relay with a test lamp from

5 terminal 87A to B+.
7998 -
MD-lsuzu
DRL Indicator Inoperative (cont'd)

6 terminal 85 to ground.

Repair the open inCKT 22 (BLK) between the panel
7 lamp/DRL relay and G105.

8 terminal 36 to B+.
Repair the open in CKT 726 (ORN) between the IP fuse

9 block and the panel lamp/DRL relay.
Replace the panel lamp/DRL relay.

10

Backprobe diode module 2 with a test lamp from
11 terminal 2B to B+.

Repair the open in CKT 718 or CKT 722 (RED/BLK)
12 between the panel lamp/DRL relay and diode module 2.

Is there an open in CKT 723 (RED/YEL) between diode
13
module 2 and S313? Go to Step 14 Go to Step 15

Repair the open in CKT 723 (RED/YEL) between diode
14 module 2 and S313.
Replace diode module 2.

15

Dome Lamps Inoperative with LF Door Open

1. Disconnect the dome lamp harness connector.
1 2. Connect a test lamp between terminal 1 and
terminal 2 in the dome lamp connector.

Replace the dome lamp assembly.
2
Does the dome lamp operate when the door is open? System OK Go to Step 3
1. Do not disconnect the test lamp. Remove diode
module D202 from joint connector 1 (upper).
3 2. Connect a jumper between terminal 1J and
terminal 1 H in the joint connector socket.

Replace diode module D202.
4
Does the dome lamp operate when the door is open? System OK Go to Step 5
1. Do not disconnect the test lamp or the jumper.

Disconnect the harness connector from the door
switch.
5
2. Connect jumper between the door switch connector

a
and chassis ground.

1998 -
MD-lsuzu
Dome Lamps Inoperative with LF Door Open (cont'd)

Replace the door switch.
6

Does the dome lamp operate when the door is open? System OK
Locate and repair the open in one or more of the
following circuits between the dome lamp switch and the
door switch:
. CKT 2 (RED/YEL)
7
CKT 149 (RED/YEL)

. CKT 26 (RED/BLK)
. CKT 148 (RED/BLK)
Does the dome lamp operate when the door is open? System OK
Hazard Lamps Inoperative

1. Turn the hazard switch to the ON position.
2. Disconnect the harness connector from the

turn/hazard flasher.
1 3. Connect a self powered test lamp between
terminal 8 and ground.
4.Connect a self powered test lamp between

Does the test lamp light for both checks? Go to Step 2 Go to Step 3
Replace the turn/hazard flasher.

2

Replace the turn signal/hazard switch.
3
Headlamps Inoperative -
Left Low Beam
Backprobe the left headlamp with a fused jumper from
1 terminal B to ground.
Does the headlamp light? Go to Step 2 Go to Step 3
Repair the open in CKT 691 (RED/BLK) between the left

2 headlamp and S315.
Does the headlamp light? System OK
Replace the left headlamp.

3
Does the headlamp light? System OK
Headlamps Inoperative - Right Low Beam

Backprobe the right headlamp with a fused jumper from
1 terminal B to ground.
Does the headlamp light? Go to Step 2 Go to Step 3
Repair the open in CKT 697 (RED/BLK) between the right

2 headlamp and S315.
Does the right headlamp light? System OK

Replace the right headlamp.
3
Does the right headlamp light? System OK
1998 -
MD-lsuzu
Low Beams (DRL Off)
1. Place the headlamp switch in the HEAD and LO

positions.
1
2. Backprobe the headlamp switch with a test lamp
from terminal 1 to B+.

Backprobe the headlamp switch with a test lamp from

2 terminal 4 to B+.

Repair the open in CKT 87 (BLK) between the headlamp
3 switch and G105.
Do the headlamps light? System OK

Backprobe the lighting relay with a test lamp from

Replace the headlamp switch.
5


Repair the open in CKT 717 (RED/BLK) between the
7 lighting relay and the headlamp switch.


9 block and the lighting relay.


Backprobe the low/high lighting relay with a test lamp from

Repair the open in CKT 691 (RED/BLK) between S315
12 and the lighting relay.

Replace the lighting relay.
13


Repair the open in CKT 720 (BLK) between the low/high
15 lighting relay and G105.

Repair the short to ground in CKT 721 (RED/YEL)
between the low/high lighting relay, diode module 2, the
16
instrument cluster, and the headlamp switch.

1998 -
MD-lsuzu
Low Beams (DRL Off) (cont'd)

Repair the open in CKT 716 (YEL) between the lighting
18 relay and the low/high lighting relay.
Replace the low/high lighting relay.

19
Low Beams (During DRL Operation)
Is the vehicle equipped with hydraulic brakes instead of
1
air brakes? Go to Step 2 Go toStep 8
Backprobe the park brake switch with a test lamp from

2 terminal 4 to B+.

Locate and repair the open in CKT 6 and CKT 27 (BLK)
3 between the park brake switch and G105.
Do the low beam filaments light during DRL operation? System OK Go to Step 4
1. Backprobe the park brake switch with a test lamp
4
2. Disengage the park brake.

Replace the park brake switch.
5
Backprobe the DRL OFF relay with a test lamp from

Does the test lamp light? Go to Step 14 Go toStep 7
Locate and repair the open in CKT 5 and CKT 745 (BLU)
7 between the DRL OFF relay and the park brake switch.
Backprobe the park brake switch with a test lamp from
8 terminal B to B+.

Locate and repair the open in CKT 746 (BLK) between the
9 park brake switch and G105.
Do the low beam filaments light during DRL operation? System OK
1. Backprobe the park brake switch with a test lamp

from terminal A to B+.
10

Replace the park brake switch.
11


Locate and repair the open in CKT 744 (LT BLU) between
13 the DRL OFF relay and the park brake switch.
1998 -
MD-lsuzu
Headlamps Inoperative
Low Beams (During DRL Operation) (cont'd)

2. Backprobe the DRL OFF relay with a test lamp from
14
terminal 85 to chassis ground.

Locate and repair the open in CKT 743 (BRN) between

15 the IP fuse block and the DRL OFF relay.

17 DRL OFF relay and G105.


Replace the DRL OFF relay.
19

Backprobe the DRL ON relay with a test lamp from

Repair the open in CKT 744 (DK GRN) between the
21 DRL ON relay and the DRL OFF relay.
2. Backprobe the DRL ON relay with a test lamp from

22
terminal 86 to B+.
Inspect for a short to ground in CKT 740 (BRN) between
23 the DRL ON relay and joint connector 2.
Is the circuit in need of repair? Go to Step 24 Go to Step 25

Repair the short to ground in CKT 740 (BRN) between the
24 DRL ON relay and joint connector 2.

Refer to Engine Electrical in order to diagnose the
25 charging/generator system. Perform repairs as necessary.

1. Stop the engine.
26 Backprobe the DRL ON relay with a test lamp from
3.
terminal 85 to chassis ground.
Does the test lamp light? Go toStep 28 Go to Step 27
27 the IP fuse block and the DRL ON relay.

Backprobe the DRL ON relay with a test lamp from

Replace the DRL ON relay.
29
1998 -
MD-lsuzu
Low Beams (During DRL Operation) (cont'd)
Backprobe the DRL series dropping resistor with a test
30 lamp from terminal A to B+.

Locate and repair the open in CKT 729 (RED/BLK)
between the DRL series dropping resistor and the
31
DRL ON relay.


1. Disconnect the DRL series dropping resistor.
32 2. Connect a fused jumper from the DRL series
dropping resistor connector terminal A to B.

Do the low beam filaments light? Go to Step 33 Go to Step 34
Replace the DRL series dropping resistor.

33
Do not disconnect the jumper. Backprobe the lighting relay

34 witha test lamp from terminal 87A to B+.
Does the test lamp light? Go to Step 36 Go toStep 35

Locate and repair the open in CKT 715 (RED/YEL)
between the lighting relay and the DRL series dropping
35
resistor.
36
Headlamps -
Low Beams On with Headlamp Switch Off (DRL Off)
Disconnect the headlamp switch.
1
Did the headlamps turn off? Go to Step 3 Go to Step 2


3
Repair the short to ground in CKT 717 or CKT 718

(RED/BLK) between the headlamp switch, diode module 2,
4
and the lighting relay.

Did the headlamps turn off? System OK
Disconnect the lighting relay.
5
Connect a test lamp from lighting relay connector

Repair the short to ground in CKT 691 or CKT 697

(RED/BLK) between the left headlamp, the right headlamp,
7
and the lighting relay.


Disconnect the DRL Off relay.
8

9
1998 -
MD-lsuzu
Headlamps -
Low Beams On with Headlamp Switch Off (DRL Off) (cont'd)
Replace the DRL Off relay.

10

Disconnect the DRL On relay.

11

Repair the short to ground in CKT 744 (DK GRN) between
12 the DRL Off relay and the DRL On relay.

Disconnect the DRL series dropping resistor.
13

Inspect for a short to ground in CKT 729 (RED/BLK)
between the DRL series dropping register and the DRL
14
on relay.
Is the connection OK? Go to Step 16 Go to Step 17
15
resister.
16

Repair the connection.
17
Headlamps -
Low Beams On with Headlamp Switch Off (During DRL Operation)
1. Disconnect the lighting relay.
1 2. Backprobe the headlamp switch with a test lamp

Inspect for a short to ground in CKT 717 (RED/BLK)
2 between the lighting relay and the headlamp switch.
Does a short to ground exist? Go to Step 4 Go to Step 5

1. Connect the lighting relay.
2. Disconnect the DRL series dropping register.
3

Are the headlamps lit? Go to Step 6 Go to Step 7
Repair the short to ground in CKT 717 (RED/BLK)
4 between the lighting relay and the headlamp switch.

5

Inspect for a short to ground in CKT 715 (RED/YEL)
6
register.
Does a short to ground exist? Go to Step 8 Go to Step 9

7
1998 -
MD-lsuzu
Headlamps -
Low Beams On with Headlamp Switch Off (During DRL Operation) (cont'd)
8
register.


9
Left High Beam (Filament)
Backprobe the left headlamp with a test lamp from
1 terminal A to B+.

2
Did the headlamp light? System OK

Repair the open in CKT 690 or CKT 696 (BLK/WHT)
3 between the left headlamp and S317.
Left High Beam (Headlamp)
Backprobe the left HI beam headlamp with a test lamp
1 from terminal B to ground.

Backprobe the left HI beam headlamp with a test lamp
2 from terminal C to B+.
Repair the open in CKT 688 (RED/YEL) between S229

3 and the left HI beam headlamp.
Replace the HI beam headlamp.

4
Repair the open in CKT 692 or CKT 696 (BLK/WHT)

5 between the left HI beam headlamp and S317.
Headlamps Inoperative - Right High Beam (Filament)

Backprobe the right headlamp with a test lamp from

1 terminal A to B+.

2
Repair the open in the CKT 696 (BLK/WHT) between the

3 right headlamp and S317.
1998 -
MD-lsuzu
Headlamps Inoperative - Right High Beam (Headlamp)

Backprobe the right HI beam headlamp with a test lamp
1 from terminal C to ground.

Backprobe the right HI beam headlamp from
2 terminal B to B+.
Repair the open in CKT 695 (BLK/WHT) between S230

3 and the right HI beam headlamp.
Replace the right HI beam headlamp.

4
Repair the open in the CKT 698 (BLK/WHT) between the

5 right HI beam headlamp and S317.
High Beams
1 terminal 1 to B+.

2 terminal 3 to B+.

3 switch and G105.


5


Repair the open in CKT 721 (RED/YEL) between the
7 low/high lighting relay and the headlamp switch.

Backbrobe the low/high lighting relay with a test lamp from

9 block and the low/high lighting relay.
Do the headlamps work? System OK

1998 -
MD-lsuzu
High Beams (cont'd)
Repair the open CKT 720 (BLK) between low/high
in
11 lighting relay and G105.

Repair the open CKT 696 (BLK/WHT) between 8317
in
12 and the low/high lighting relay.
Replace the low/high lighting relay.

13
Flash to Pass
1 terminal 5 to B+.

2

3 switch and G105.
One Lamp (Left)
Backprobe the left headlamp with a test lamp from
1 terminal C to ground.

2
Repair the open in CKT 689 or CKT 688 (RED/WHT)

3 between the IP fuse block and the left headlamp.
One Lamp (Right)
Backprobe the right headlamp with a test lamp from

1 terminal C to ground.

2

Repair the open in CKT 694 or CKT 695 (RED/WHT)
3 between the IP fuse block and the left headlamp.
1998 -
MD-lsuzu
Headlamps, DRL On with Engine Not Running

Step Action Value(s) | Yes No
Definition: DRL Does Not Disengage When Engine is Not Running.
1 2. Backprobe the DRL ON relay with a test lamp from
terminal 86 to B+.
Repair the short to CKT 740 (BRN) between the
ground in
2 DRL ON relay and the generator?

Replace the DRL ON relay.
3
Does the DRL disengage when the engine is not runing? System OK
High Beam Indicator Inoperative

2. Place the headlamp switch in the HI position.

1 test lamp
Backprobe the instrument cluster with a

3.
from terminal A6 to ground.
Backprobe the instrument cluster with a test lamp from
2 terminal A14 to B+.

Repair the open in CKT 1 or CKT 371 (BRN) between the
3 IP fuse block and the instrument cluster.
Does the HI beam indicator light? System OK
Repair or replace the instrument cluster.

4

5 terminal 3 to B+.

Repair the open in CKT 14 or CKT 82 (RED/YEL)
6 between the instrument cluster and the headlamp switch.

7 terminal 5 to B+.

8 terminal 1 to B+.

9 switch and G105.


10

11 switch and G105.
1998 -
MD-lsuzu
Instrument Panel Lamps Inoperative (Dimming Lamps Inoperative)

Place the headlamp switch in the PARK position.
1
Are the tail lamps ON? Go to Step 11 Go to Step 2
1. Remove the taillamp relay from the socket.

2. Connect a DVM between socket terminal 85 and
2
ground.
Does the DVM indicate voltage? Go to Step 4 Go to Step 3
Locate and repair the open in CKT 93 (ORN) to the tail
3 lamp relay.
Are the instrument panel dimming lamps still inoperative? Go to Step 4 System OK
Connect an ohmmeter between socket terminal 86 and

4 chassis ground.
Did the ohmmeter indicate continuity? Go to Step 5 Go to Step 6
Replace the tail lamp relay.

5
Connect an ohmmeter between headlamp switch terminal 2

Locate and repair the open in CKT 85 (GRN/WHT).
7
Connect an ohmmeter between headlamp switch terminal 1

Locate and repair the open in the ground wire 4 (BLK)
9 between G105 and terminal 1 in the headlamp switch.

10
1. Turn the headlamp illumination control counter

clockwise to the dimmest position.
2. Remove the buss connector from joint

11 connector 3 (upper).
3. Connect a test lamp between terminal A and chassis

ground.
Replace joint connector 3 (upper) buss connector.

12
1. Connect a jumper between terminal A in the joint

connector 3 (upper) connector.
2. Disconnect the 17-way harness connector from the
IP cluster.
13

terminal C2 in the 17-way IP cluster harness
Repair the open in CKT 3 (BLK/RED) between terminal A

in the joint connector 3 (upper) connector and terminal C2
14 in the 17-way IP cluster harness connector.

Connect a test lamp between terminal C1 in the 17-way IP

15 cluster harness connector and chassis ground.
1998 -
MD-lsuzu
Instrument Panel Lamps Inoperative (Dimming Lamps Inoperative) (cont'd)

16 terminal C1 in the 17-way IP cluster harness connector.
1. Disconnect the 15-way IP cluster harness connector.
a test lamp between terminal A9 in the
2. Connect
17 15-way IP cluster harness connector and terminal C1
in the 17-way IP cluster harness connector.
Replace the IP cluster.

18
Are the instrument panel dimming lamps still inoperative? System OK
Locate and repair the open in the ground wire 4 (BLK)

between G105 and terminal A9 in the 15-way IP cluster
19
harness connector.
Are the instrument panel dimming lamps still inoperative? System OK
Instrument Panel Lamps Inoperative (Always at Full Brightness)

1. Set the headlamp switch to the OFF position.
2. Disconnect the 17-way IP cluster harness connector.
3. Remove the buss connector from joint
connector 3 (upper).
1
Using

4. self-powered test lamp connected to

a
chassis ground, probe each terminal inside joint

connector 3 (upper).
Does the test lamp light in any probed joint connector
terminal? Go to Step 2 Go to Step 3
Locate and repair the short to ground in the affected
circuit.
2
Does the illumination control dim the instrument

panel lamps? System OK
Replace the IP Cluster.

3 Does the illumination control dim the instrument
panel lamps? System OK
License and Tail Lamps Inoperative (License and Tail Lamps)

1. Disconnect the harness connector from the right tail
stop/turn lamp assembly.
1
3. Connect a test lamp between terminal B on the right

tail stop/turn lamp harness connector and ground.
Connect a test lamp between terminals B and E on the
2 right tail stop/turn lamp harness connector.
1998 -
MD-lsuzu
License and Tail Lamps Inoperative (License and Tail Lamps) (cont'd)
Repair the open CKT 9 (BRN) between S901 and
terminal B in the right tail stop/turn lamp harness
3
connector.
Repair the open in the right park/turn lamp assembly.

4
Repair the open in CKT 150 (BLK) between S400 and

terminal E in the right tail stop/turn lamp harness
5
connector.
License and Tail Lamps Inoperative (Left Rear Taillamp Inoperative)

Definition: Left Rear Taillamp Is Inoperative.
1. Disconnect the harness connector from the Left Rear

Stop and Turn Lamp assembly.
2. Set the Headlamp Switch to the PARK position.

1
3. Connect a test lamp between terminal B on the Left

Rear Stop and Turn Lamp harness connector and

the chassis ground.
Connect a test lamp between terminals B and terminal E

2 on the Left Rear Stop and Turn Lamp harness connector.

Repair the open in CKT 9 (BRN) between S 901 and
terminal B in the Left Rear Stop and turn Lamp Harness
3
Connector.
Repair the open in the Left Rear Park and Turn Lamp
4 assembly.
Repair the open in CKT 150 (BLK) between S 400 and

terminal E in the Left Rear Stop and Turn Lamp Harness
5
Connector.
1998 -
MD-lsuzu
License and Tail Lamps Inoperative (Both Taillamps Inoperative)

Definition: Both Rear Taillamps are Inoperative.
1. Disconnect the harness connector C 402.
2. Set the Headlamp Switch to the PARK position.

1 3. Connect a test lamp between terminal A in the C 402
Front Chassis Harness Connector and the chassis

ground.
1. Disconnect the harness connector from the Right

Rear Stop and Turn Lamp assembly.
2. Connect a self powered test lamp between
2 terminal B in the Right Tail Stop and Turn Lamp
Harness Connector and terminal A in C 402, the

Rear Chassis Harness Connector.
3 terminal A in C 402, the Front Chassis Harness Connector.

Repair the open in CKT 150 (BLK) between S 400
4 and G 404.

5 terminal A in C 402, the Rear Chassis Harness Connector.
Park Lamps Inoperative -

Front
1
3. Connect a test lamp between terminal A in the C105

front chassis harness connector and ground.

Connect a test lamp between terminals A and D on the
2 C105 front chassis harness connector.

Repair the open in (BRN) between S126 and
CKT 9
3 terminal A in the C105 front chassis harness connector.
1. Disconnect the harness connector from the right front

park/turn lamp assembly.
2. Connect a self powered test lamp between terminal B
4 in the right front park/turn lamp harness connector
and terminal D in the C105 front turn signal harness

connector.
Repair the open in CKT 150 (BLK) between G107 and
5 terminal D in the front chassis harness connector C105.
7998 -
MD-lsuzu
Park Lamps Inoperative -

Front (cont'd)
Repair the open in CKT 150 (BLK) between S105 and
6 terminal D in the front turn signal harness connector C105.
Repair the open in CKT 9 (BRN) between 8102 and
7 terminal A in the front turn signal harness connector.
Park Lamp Inoperative -

LF
Definitiori: Left Front Park Lamp Inoperative.
1. Disconnect the harness connector from the Left park

and turn lamp assembly.
2. Set the Headlamp Switch to PARK.
1
3. Connect a test lamp between terminal C on the Left

park and turn lamp harness connector and the

chassis ground.
Connect a test lamp between terminal C and terminal B on
2 the Left park and turn lamp harness connector.
Repair the open CKT 9 (BRN) between S 102 and

terminal C in the Left park and turn lamp harness
3
connector.
Repair the open in Left park and turn lamp assembly.
4

Repair the open in CKT 150 (BLK) between S 105 and
terminal B in the left park and turn lamp harness
5
connector.

RF
Definition: Right Front Park Lamp Inoperative.
1. Disconnect the harness connector from the right park

and turn lamp assembly.
2. Set the Headlamp Switch to PARK.
1
3. Connect a test lamp between terminal C on the right

park and turn lamp harness connector and the

chassis ground.
Connect a test lamp between terminal C and terminal B on

2 the right park and turn Lamp harness connector.

Repair the open in CKT 9 (BRN) (9) between S 102 and
terminal C in the right park and turn lamp harness
3
connector.
1998 -
MD-lsuzu

RF (cont'd)
Repair the open in Right park and turn Lamp assembly.
4

Repair the open in CKT 150(BLK) between S 105 and
terminal B in the right park and turn lamp harness
5
connector.
Park, Side, and Front Marker Lamps Inoperative

Definition: All Park Lamps, Side and Front Marker Lamps Are Inoperealive (Tractor)
1. Remove the taillamp relay.
1 Connect a test lamp between terminal 85 in the

2.
taillamp relay socket and the chassis ground.

Repair the open in CKT 91 (GRN) between S289

2 and S232.

Repair the open in CKT 91 (GRN) between S232 and
3 Circuit Breaker #19.
Park, Side Marker, and Clearance Lamps Always On

Definition: Park, Side Marker and Clearance Lamps Are always On (Trailer Only)
1. Place the Headlamp switch in the OFF position.

1
2. Remove the Taillamp Relay from the relay socket.

Do the side marker and clearance lamps remain ON? Go to Step 2 Go to Step 3
Locate and repair the short to voltage in CKT 94 (BRN)
2 connected to terminal 87 in the Taillamp relay socket.
Connect a test lamp between terminal 86 and terminal 85

3 in the Taillamp relay socket.
1. Keep the test lamp connected.
4 2. Disconnect the harness connector from the
Headlamp Switch
Replace the Taillamp Relay.

5
Repair the short to ground in the CKT 85 (GRN/WHT)

between terminal 2 in the headlamp switch harness
6
connector and terminal 86 in the Taillamp Relay socket.


Replace the headlamp Switch.
7
1998 -
MD-lsuzu
Park, Side Marker, and Clearance Lamps Inoperative

Definition: All Park, Side Marker and Clearance Lamps Are Inoperative (Trailers).
1. Place the headlamp switch in the PARK position.
2. Remove the taillamp relay.

1
3. Connect a test lamp between terminal 85 and

terminal 86 in the taillamp relay socket.

Connect test lamp between terminal 30 and terminal 86 in
a
2 the taillamp relay socket.

Connect test lamp between the taillamp relay socket
a
3 terminal 85 and the chassis ground.

Connect test lamp between terminal 30 and terminal 87
a in
4 the taillamp relay socket.

Repair the open CKT 91 (ORN) between terminal 30 in the
5 taillamp relay socket and S232.
1. Keep the headlamp switch in PARK.
6 Connect a self powered test lamp between terminal 86

2.
in the taillamp relay socket and the chassis ground.
Repair the open in CKT CKT 93 (ORN) between Circuit

91 or
7 Breaker #19 and the taillamp relay socket terminal 85.

Replace the taillamp relay.
8

Repair the open in CKT 94 (BRN) between S321 and the
9 taillamp relay socket terminal 87.

Replace the Taillamp Relay.
10
1. Disconnect the headlamp switch harness connector.
2. Connect a self powered test lamp between terminal 2 on

11 the headlamp switch connector and terminal 86 in the
taillamp relay socket.

Replace the Headlamp Switch.

12

Repair the open CKT 85 (GRN/WHT) between terminal 2 in
the Headlamp Switch and terminal 86 in the taillamp relay
13
socket.
1998 -
MD-lsuzu
Rearview Mirror Lamps Inoperative -

Outside (Both Mirrors)
1 2. Connect a test light between terminal A in the
interior body builder connector and ground.

2 2. Connect a self powered test light between terminals
E1 and E2 in the upper IP harness connector C212.

Repair the open in CKT 95 (BRN) between 8319
3 and S320.

Repair the open in CKT 342 (ORN) between S342 and
4 terminal E2 in the upper IP harness connector C212.
1. Disconnect the lighted mirror jumper C216.
5 2. Connect a self powered test lamp between
terminals 2 and 5 in the lighted mirror jumper C216.

Connect a self powered test lamp between terminal 2 in
the upper IP lighted mirror jumper socket C216 and
6
terminal E2 in the upper IP harness connector C212.


Repair the open in CKT 147 (BRN) in the lighted mirror
7 jumper C216.

Repair the open in CKT 2 or CKT 145 (BRN) between
terminal 5 in the lighted mirror jumper socket C216 and
8
terminal E1 in the upper IP harness connector C212.


Repair the open in CKT 142 (ORN) between terminal 2 in
the lighted mirror jumper socket C216 and terminal E2 in
9
the upper IP harness connector C212.

Rearview Mirror Lamps Inoperative -

Outside (Right Mirror)
1 2. Connect a test light between terminal A in the lighted
mirror right door connector and ground.

Connect a test light between terminals A and B in the

2 lighted mirror right door connector.

Repair the open CKT 1, CKT 32 or CKT 342 (ORN)
in
between S342 and terminal A in the lighted mirror right
3
door harness connector.

1998 -
MD-lsuzu
Rear-view Mirror Lamps Inoperative -

Outside (Right Mirror) (cont'd)
Repair the open in right lighted mirror assembly.
4

Repair the open in CKT 2, CKT 4, CKT 33, CKT 68,
CKT 550 or CKT 720 (BLK) between G105 and terminal B
5
in the lighted mirror right door harness connector.

Rear-view Mirror Lamps Inoperative -

Outside (Left Mirror)
1 2. Connect a test light between terminal A in the lighted
mirror left door connector and ground.

Connect atest light between terminals A and B in the
2 lighted mirror left door connector.

Repair the open in CKT 1, CKT 32 or CKT 343 (ORN)
between S342 and terminal A in the lighted mirror left door
3
harness connector.
Repair the open in left lighted mirror assembly.

4
Repair the open in CKT 2, CKT 4, CKT 22, CKT 33,

CKT 69 or CKT 650 (BLK) between G105 and terminal B
5
in the lighted mirror left door harness connector.


One Lamp (Left)
2. Disconnect the left door harness side marker lamp

connector in the left door outer trim panel.
1
3. Connect a test lamp between terminals A and B in

the left door harness side marker lamp connector.
Repair the open in left door side marker lamp assembly.

2
Connect a test lamp between terminal A and ground on

3 the left door harness side marker lamp connector.

A and D on
4 2. Connect a test lamp between terminals
the lower IP harness connector C501.


5 terminal A in the lower IP harness connector C501.
1998 -
MD-lsuzu
One Lamp (Left) (cont'd)
Repair the open in CKT 4 (BLK) between terminal D on
the left door harness connector C501 and the left door
6
harness side marker lamp connector.

Locate and repair the open in CKT 68 or CKT 550 (BLK)
between G105 and terminal D in the lower IP harness
7
connector C501.

One Lamp (Right)
2. Disconnect the right door side marker lamp

connector in the right door outer trim panel.
1
3. Connect a test lamp between terminals A and B in

the right door side marker lamp connector.
Repair the open in right door side marker lamp assembly.
2

Connect a test lamp between terminal A and ground on
3 the right door harness side marker lamp connector.
2. Connect a test lamp between terminals A and D on

4
the lower IP harness connector C601.

5 terminal A in the lower IP harness connector C601.

Repair the open in CKT 4 or CKT 21 (BLK) between
terminal D on the right door harness connector C601 and
6
the right door harness side marker lamp connector.


Locate and repair the open in CKT 69 or CKT 650 (BLK)
between G105 and terminal D in the lower IP harness
7
connector C601.
1998 -
MD-lsuzu
Side Marker Lamps Inoperative
DEFINITION: The tractor marker lamps are inoperative.
1. Set the headlamp switch to PARK.
2. Remove the marker lamp relay.

1
3. Connect a test lamp between terminal 30 in the

taillamp relay socket and the chassis ground.

Is the test lamp lit? Go to Step 2 Go to Step 3
1. Disconnect the harness connector C 212.
2. Connect a test lamp between terminal D 1 in C 212

2 the lower IP harness connector and the chassis
ground.
Repair the open in CKT 178 (GRN) between S289 and
3 terminal 30 in the marker lamp relay socket.
1. Set the marker lamp switch to the ON position.

4 terminals D 1 and D 2 in C 212 the upper IP
harness connector.
Repair the open in CKT 175 (QRN) between S289 and
5 terminal D 1 in C212 the lower IP harness connector.
1. Reconnect C212 the upper IP harness connector.
6 2. Connect a test lamp between terminal 85 in the
marker lamp relay socket and the chassis ground.

Connect test lamp between terminal 85 and terminal 86

a
7 in the marker lamp relay socket.
Repair the open CKT 176 (ORN) between terminal 85

in in
the marker lamp relay socket and terminal D 2 in C 212
8
the lower IP harness connector.

1. Disconnect C208 the harness connector.
2. Connect a test lamp between terminal D and

terminal E in the C 208 lower IP harness connector.
9
3. Connect a jumper between terminal 30 and

terminal 87 in the marker lamp relay socket.
Repair the open CKT 22.CKT 179 or CKT 650 (BLK)

between G 105 and terminal 86 in the marker lamp relay
10
socket.
1. Remove the bulb from the right front ID lamp.

A and terminal B
2. Connect a jumper between terminal
in the right front ID lamp bulb socket.
11

terminal D and terminal E in the C 208 lower IP

harness connector.
1998 -
MD-ISUZU
Side Marker Lamps Inoperative (cont'd)

1. Keeep the jumper connected.

2. Connect a test light between terminal
E in the C208
12 of the lower IP harness connector and the chassis
ground.
Replace the marker lamp relay.

13
Repair the open in Roof Harness CKT 5 (BRN) between

the S 365 and C 208 terminal E, or the CKT 4 (BLK)
14
between the S 371 and C 208 terminal D.

Repair the open CKT 22, CKT 25, CKT 69 or CKT 650
in
(BLK) between G 105 and terminal D in the C 208 of the
15
lower IP harness connector.

1. Keep the jumper connected.
16 2. Connect a test light between terminal 2 in the trailer
connector and the chassis ground.

in
17 terminal E in the C 208 of the lower IP harness connector.

in
18 terminal 87 in the marker relay socket.
1. Keep the self powered test lamp connected.
2. Disconnect the harness connector from the marker

lamp switch.
19 Connect a jumper between terminal 1 and terminal 2

3.
in the upper IP harness marker lamp switch
connector.
Replace the marker lamp switch.
20
Connect a self powered test lamp between terminal D 1 in

C 212 the upper IP harness connector and terminal 1 in
21
the marker lamp switch connector.

Repair the open in CKT 112 (ORN) between terminal D 2
in C 212 the upper IP harness connector and terminal 2 in
22

Repair the open CKT 111 (GRN) between terminal D 1

in
in C 212 the Upper IP Harness connector and terminal 1
23 in


1998 -
MD-lsuzu
Headlamp Aiming
Tools Required
J 25300-E Headlight Aimer
The headlamps are aimed vertically and horizontally
by adjusting the two screws that move the mounting
bracket against the tension of the coil spring. The
adjusting screws (1, 2) are located in the headlamp
bezel area. One screw is above the headlamp and
the other screw is on the right side of the headlamp.
The screw (1) directly above the headlamp adjusts
the vertical position. The screw (2) to the right of the
headlamp adjusts the horizontal position.
Using the J 25300-E, adjust the headlamps to the
specifications required by the state and/or local
authorities. Follow the manufacturer's instructions for
tool use.
200966
Marker Lamp Replacement -
Side (Housing)
Removal Procedure
1. Turn OFF the headlamp switch.
3. Remove the side marker lamp lens
hold-down screw.
4. Remove the lens.
5. Remove the side marker lamp insulator by
pulling the socket and the harness assembly
through the insulator.
6. Disconnect the side marker lamp electrical

connector.
7. Remove the lamp housing.
1. Connect the side marker lamp electrical
connector.
2. Install the side marker lamp insulator and the
housing as follows:
2.1. Push the socket and the harness

assembly into the insulator.
2.2. Align the housing with the holes in
the cab.
3. Install the side marker lamp lens.

4. Install the lens hold-down screw.
214293
1998 -
MD-ISUZU
Park/Turn Signal Lamp

Replacement (Housing)
Removal Procedure
3. Disconnect the front directional signal lamp
housing electrical connector.
4. Remove the two lamp housing retaining nuts.

5. Remove the backing plate.
214289
1. Install the front directional signal lamp housing.
2. Install the lamp housing backing plate.

and Notices.
3. Install the two retaining nuts.
Tighten
Tighten the two retaining nuts to 8 N.m
(71 Ib in).
4. Connect the lamp housing electrical connector.
214289
Clearance Lamp Replacement

(Lamp Housing)
Removal Procedure
3. Remove the clearance lamp lens hold-down
screws.
4. Remove the clearance lamp lens.
5. Remove the insulator by pulling the socket and
harness assembly through the insulator.
6. Disconnect the clearance lamp electrical
connector.
214280
1998 -
MD-ISUZU
1. Connect the clearance lamp electrical
connector.
2. Install the lamp insulator and the housing.
2.1. Push the socket and the harness

assembly into the insulator.
2.2. Align the housing with the holes in

the cab.
3. Install the clearance lamp lens.
4. Install the lens hold-down screws.
214280
DRL Relay Replacement

Removal Procedure
1. Turn the headlamps and the engine OFF.
3. Remove the instrument panel lower trim. Refer
to IP Cluster Replacement (Instrument Cluster)
and IP Cluster Replacement (Speedometer) in
Instrument Panel and Gauges.
4. Disconnect the daytime running lamp relay from
the relay harness.
214306
1. Connect the DRL relay into the relay harness.
2. Install the instrument panel lower trim. Refer to
IP Cluster Replacement (Instrument Cluster)
and IP Cluster Replacement (Speedometer) in
Instrument Panel and Gauges.
214306
1998 -
MD-lsuzu
IP Lamp Replacement
Removal Procedure
1. Remove the instrument cluster. Refer to IP
Cluster Replacement (Instrument Cluster) and
IP Cluster Replacement (Speedometer) in
Instrument Panel, Gauges and Console.
2. Remove the instrument cluster bulb assembly
from the instrument cluster by turning the bulb
assembly to the left.
201013
1. Install the instrument cluster bulb assembly to
the instrument cluster.
2. Turn the bulb assembly to the right to secure
the bulb to the instrument cluster.
3. Install the instrument cluster. Refer to IP Cluster
Replacement (Speedometer) and IP Cluster
Replacement (Instrument Cluster) in Instrument
Panel, Gauges and Console.
201013
Dome Lamp Replacement (Housing)

Removal Procedure
2. Remove the dome lamp lens.
3. Remove the dome lamp bulb.
3.1. Grasp the bulb in the center.
3.2. Pull the bulb straight out.
4. Remove the two retaining screws from the lamp
housing.
5. Remove the dome lamp housing.
214308
1998 -
MD-lsuzu
1. Install the dome lamp housing to the roof with
the two retaining screws.
2. Install the dome lamp bulb by pushing the bulb
straight into the lamp housing until the bulb is
fully seated.
3. Install the dome lamp lens.
214308
Tail Lamp Replacement (Bulb)
Removal Procedure
3. Remove the taillamp lens from the lens
housing.
3.1. Roll back the rubber housing boot.
3.2. Pull the lens from the lamp housing.
200974
4. Remove the taillamp bulb.

4.1. Press the bulb into the socket.
4.2. Turn the bulb to the left.
4.3. Pull the bulb out.
200976
1998 -
MD-ISUZU
1. Install the taillamp bulb.
1.1. Press the bulb into the socket.

1.2. Turn the bulb to the right.
200976
2. Install the taillamp lens into the rubber

housing boot.
Make sure that the lens is fully seated.
200974
Tail Lamp Replacement (Housing)
Removal Procedure
3. Disconnect the taillamp switch electrical
connector.
4. Remove the taillamp assembly.
5. Remove the taillamp.
200980
1998 -
MD-lsuzu
1. Install the taillamp by aligning the locator with
the hole in the frame rail.
and Notices.
Important: Make sure that the taillamp harness
retaining clip is secured by the retaining bolt.
2. Install the retaining bolt into the taillamp

assembly.
Tighten
Tighten the retaining bolt to 35 N.m (26 Ib ft).
3. Connect the taillamp electrical connector.

200980
Clearance Lamp Replacement -

Outside
Mirror (Housing)
Removal Procedure
3. Remove the illuminated mirror clearance lamp
lens by unsnapping the lens from the lens
housing.
4. Remove the two lamp housing retaining screws.
5. Disconnect the lamp electrical connectors.
200969
1. Install the illuminated mirror clearance lamp
housing.
2. Connect the clearance lamp electrical
connectors.
3. Install the two lamp housing retaining screws.
4. Install the lens by snapping the lens onto the
lens housing.
200969
7998 -
MD-ISUZU
Description and Operation the DRL Off relay through the CKT 744 (DK GRN) to
the normally closed contacts of the DRL On relay.
Lighting System Description The DRL On relay will energize and open up its
contacts when the ignition switch is in the RUN
position and the engine is not running. The ground
License Plate Lamp Replacement
path is now provided through CKT 729 (RED/BLK),
The taillamp bulb also functions as the license plate through the DRL series dropping resistor, and
lamp bulb. When the taillamps are turned on, the through CKT 715 (RED/YEL) to the normally closed
taillamp bulb shines through a clear lens at the
contacts of the lighting relay. The low beam filaments
bottom of the taillamp housing.
now light at 90 percent intensity because of the
additional voltage drop across the DRL series
DRL Circuit Description dropping resistor.
Circuit breaker #14 applies voltage to all of the
filaments of the left headlamp at all times through Exterior Lights Circuit Description
CKT 688 or CKT 689 (RED/YEL). Circuit (Stop Lamp Circuit Operation)
breaker #15 applies voltage to all of the filaments of
the right headlamp at all times through CKT 694 or Stoplamps
CKT 695 (RED/WHT). The headlamp switch is is depressed, the Stoplamp
When the brake pedal
grounded at all times through CKT 87 and CKT 86 Switch contacts close. The Stoplamp Switch has
(BLK) to G105.
voltage available at all times from Circuit Breaker 25
(Circuit Breaker 23 on vehicles with Hydraulic
Low Beam Operation Brakes) through the Ckt 103 or Ckt 110 (ORN)
When you place the headlamp switch in the HEAD [CKT 470 (GRN/WHT) on vehicles with Hydraulic
and LO positions, the internal contacts of the switch Brakes]. When the brake pedal is depressed and the
close. This provides a path to ground the coil of the switch contacts close, this voltage energizes Ckt 104
lighting relay through CKT 717 (RED/BLK). Circuit or CKT 105 (WHT) [CKT 471 (WHT) on vehicles with
breaker #16 applies voltage at all times to the other Hydraulic brakes] to the Turn/Hazard Flasher. The
side of the lighting relay coil. When ground is Turn/Hazard Flasher is a solid state logic device
provided, the relay energizes, switching the relay which controls the operation of the Stop, Turn and
contacts. A ground path is now provided to the low Hazard lamp functions, the Turn/Hazard Flasher
beam filaments through CKT 691 or CKT 697 distributes the voltage to the Stoplamp bulbs and to
(RED/BLK), through the now closed contacts of the the Right and Left Trailer Turn Relays, which provide
relay, through CKT 716 (YEL) to the closed contacts dedicated stop lamp signals to the Trailer Wiring
of the low/high lighting relay to G105. With ground Provision Connector.
provided, the low beam filaments illuminate. These circuits are used with a dual filament, single
bulb turn/stoplamp system. The Turn/Hazard Flasher
High Beam Operation logic enables one filament in a dual filament bulb to
When the headlamp switch is in the HI or PASS operate as a turn signal lamp even though the brake
position, a ground path to the low/high lighting relay pedal is depressed. Both the Left and Right Tail
is provided through CKT 721 (RED/YEL). Voltage is Lamps contain dual filament bulbs as well as single
applied at all times through circuit breaker #16 and filament back-up lamp bulbs. Both bulbs in the Left
CKT 719 (ORN) to the coil of the low/high lighting and Right Tail Lamps are grounded by CKT 150
relay, causing the relay to energize. With the relay (BLK) to Ground G 404.
contacts switched, a ground path is provided to the
high beam filaments through CKT 690, CKT 692, Park and Side Marker Lamps
CKT 696 or CKT 697 (BLK/WHT) through the now The Park, Side Marker and Clearance Lamps are
closed contacts of the low/high lighting relay to energized whenever the Headlamp Switch is in the
G105. With ground provided, the high beam PARK or HEAD position. This causes a ground to be
filaments illuminate. passed through the Headlamp Switch, which
energizes the Taillamp Relay. When the Taillamp
DRL Operation Relay is energized, voltage is distributed on CKT 94
In DRL operation, ground is provided to the low (BRN) to the Front and Rear Park Lamps, the Right
beam filaments through a different circuit through the and Left Side Marker Lamps, the Right and Left Side
normally closed contacts of the lighting relay. The Mirror Lamps, the Interior Body Builder Connector,
park brake switch is grounded at all times at G105. and the Trailer Connector.
When the parking brake is disengaged, ground is Grounding for the Front Park Lamps is through
provided to one of the contacts of the DRL Off relay. CKT 150 (BLK) to ground G 107. The Clearance
The DRL Off relay is permanently grounded at G105. Lamps, the Left and Right Front Side Marker Lamps,
When the ignition switch is in the RUN position, and the Lighted Mirror Lamps are grounded through
voltage is supplied to the other side of the DRL Off CKT 550 or CKT 650 (BLK) to Ground G 105. The
relay, causing the relay to energize. The ground path Right and Left Taillamps are grounded through
is now provided through the now closed contacts of CKT 150 (BLK) to G 404.
1998 -
MD-lsuzu
Marker Lamps (Tractor only) Interior Lights Circuit Description

The Marker Lamps are located on the top front portion
of the cab. The Marker Lamps are controlled by the IP Dome Lamps
mounted Marker Lamp Switch. When the switch is The dome lamp is located within the cab in the front
pressed, current is passed through the switch on center part of the headliner. The dome lamp receives
CKT 112 (ORN) to the Marker Lamp Relay. The power through CKT 150 or CKT 1 (ORN) from circuit
Marker Lamp Relay switches power from CKT 178 breaker #7.
(GRN) to CKT 177 (BRN) when it is energized by the by completing the ground
The lamp is operated
Marker Lamp Switch. Power that is passed into circuit. The ground circuit is completed by operating
CKT 177 (BRN) is also supplied to the Trailer
the dome lamp switch (part of the dome lamp
Connector on CKT 53 (BLU) and through connector
assembly) in one of two positions. With the switch in
C 208 to the Roof Harness, where it supplies the front
the DOOR position, ground is supplied to the dome
ID Lamps and the Clearance lamps.
lamp by the door switch, through CKT 26 or
CKT 148 (RED/BLK), the diode module D 202 and
Turn Signal and Hazard Lamps CKT 2 or CKT 149 (RED/YEL). With the switch in
The Turn Signal Lamps and Hazard Lamps operate the ON position, ground is supplied through an
from the same lamps. When operating as turn signal internal chassis ground screw connection, which
lamps, ground is provided from the Turn Signal doubles as a fastener for the dome lamp to the cab
Switch through either CKT 132 (BLU/BLK) or sheet metal.
CKT 133 (BLU/ORN) to the Turn/Hazard Flasher.
This causes the Turn/Hazard Flasher to operate only Interior Lights Dimming Circuit Description
the front and rear bulbs on the selected side of the
vehicle. When operated as Hazard Lamps, ground is Circuit Operation
provided to the Turn/Hazard Flasher by the Turn
The instrument panel dimming system operates to
Signal Switch on both the Left CKT 132 (BLU/BLK)
provide a variable level of illumination at the
and the Right CKT 133 (BLU/ORN) at the same time speedometer and control switches. By adjusting the
and all four bulbs are flashed together. position of the dimmer control on the IP Cluster, a
variable voltage is supplied to the system lamps and
Backup Lights Circuit Description components.
When the ignition switch is in the RUN position,
Voltage is available at all times at circuit breaker 19.
voltage is available at the backup lamp switch from This voltage is supplied to the taillamp relay coil
circuit breaker #9 through CKT 139 (PNK). The through CKT 93 (ORN). When the headlamp switch
backup lamp switch is located on the transmission. is positioned in either the PARK or ON positions, this
When the transmission is placed into Reverse, the switch supplies a ground to the taillamp relay coil.
backup lamp switch contacts close. This applies
The taillamp relay then closes the normally open (87)
voltage through CKT 24 (LT GRN) to both backup
contact, supplying power to the panel lamps and the
lamp assemblies. Voltage is also available to the
IP dimmer switch. Ground is supplied through a
backup alarm, if equipped. The backup lamps ground variable resistance in the dimmer control. The
is provided through CKT 150 (BLK) to ground G404.
resistance depends upon the position of the dimmer
When voltage is applied while the transmission is in
control.
Reverse, the lamps illuminate. Shifting to another
gear or turning the ignition switch OFF causes the The variable resistance ground is fed to the lamps
from CKT 3 (BLK/RED) through joint connector #3.
lamps to turn off.
The joint connector is like a large splice pack. The
joint connector distributes the variable resistance
ground to the system lamps by CKT 40, CKT 173,
CKT 134, CKT 124, CKT 86, CKT 116, CKT 146,
CKT 104, CKT 39, CKT 100, CKT 353, CKT 46 or
CKT 165 (BLK/RED).
7995 -
MD-lsuzu
J25300-E
Headlamp Aimer
6302
1998 -
MD-lsuzu
Body and Accessories Wipers/Washer Systems 8-103
Wipers/Washer Systems
Wiper/Washer System Schematic References

Subsection Name
HVAC Compressor Controls Manual Cell 64 1HVAC
7998 -
MD-lsuzu
> Wipers/Washer Systems Body and Accessories
1998 -
MD-lsuzu
Component Locator
Wiper/Washer System Components

Windshield Washer On the center of the cab, under the hood, Wiper/Washer System Wiper/Washer System
Pump Motor in the windshield washer reservoir Component Views Connector End Views
On the right side of the steering column
Windshield Washer Wiper/Washer System
(part of the windshield wiper switch and
Switch Component Views

multifunction switch)
Wiper/Washer System Wiper/Washer System

Windshield Wiper Motor On the center of the cab, under the hood
On the right side of the steering column Wiper/Washer System
Windshield Wiper Switch

In the lower IP harness, part of the diode
D200 module 1, plugged into splice pack 1,
terminals A, B and C
7995 -
MD-lsuzu
8-106 Wipers/Washer Systems Body and Accessories
Wiper/Washer System Component Views

Underhood View
231456
Legend
(1) Windshield Wiper Motor (3) Windshield Washer Pump Motor
(2) Windshield Wiper Motor Connector
1998 -
MD-lsuzu
Body and Systems 8-107
Accessories____________________Wipers/Washer
228426
Legend
1998 -
MD-lsuzu
Visual Identification Windshield Washer Pump Motor
Wiper/Washer System Connector

End Views
Windshield Wiper/Washer Switch C2
n=n
Ijp^^ta)
[24][22
i] [26] [at](aj)
[27J(3C
^ J 235949
Connector Part
2 Way F
Information (GRY)
Circuit
339175
9
Switch Input
Connector Part

Way A BLU/ORN
Washer Pump
Information
Female
B BLU/RED 6 | Fuse Output Battery
Circuit
Windshield Wiper Motor
22
Not Used
Windshield Wiper
23 BRN/WHT 459
Motor Pin-5
Windshield Wiper
24 BRN/YEL 458 lllll I
Motor Pin-4 / \
^ \
25 BLK 461 Ground
Windshield Wiper aai^
26 BLU/WHT 457
Motor Pin-2 a }
27-30
Not Used \^ }
\.
238402
6 Way F
Connector Part
Information (GRN)
Circuit
1
Not Used
2 BLU/WHT 457 Intermittent
3 BLU/RED 456 Ignition
4 BRN/YEL 458 High
5 BRN/WHT 459 Low
6 BLK 460 Ground
1998
MD-lsuzu

Procedures
Wiper/Washer Diagnostic System Check

Step Action Normal Result(s) Abnormal Result(s)*
Turn the ignition switch to the ACCY The washer sprays the windshield The washer does not spray the
or the RUN position. Hold the washer until the switch is released. The windshield or complete the
switch in the ON position for 1 to wipers run at a low speed and washer cycle.
1 2 seconds. continue to run for approximately
six seconds after the washer cycle is
completed. Then the wipers return to
the park position.
Turn the wiper switch to the The wipers make one complete The wipers do not make one
INT position. Activate the sweep, then pause for 0 to complete sweep, then pause for 0 to
2
intermittent wiper function through 25 seconds before making the 25 seconds before making the
the entire range. next sweep. next sweep.
Turn the wiper switch to the INT The washer sprays as long as the The washer does not spray when the
position. Push the washer switch to washer switch is held in the ON washer switch is held in the ON
the ON position for 1 to 2 seconds. position. The wipers run at a low position. The wipers will not run at
3 speed during the spray period and all. Refer to Wipers All Modes and
continue for approximately Washer Inoperative.
six seconds after the spray cycle.
The wipers return to pulse mode.
Turn the wiper switch to the LOW The wipers run continuously at a low The wipers do not run. Refer to
4 position. speed. Wipers All Modes and Washer
Inoperative.
Turn the wiper switch to the HI The wipers run at a faster speed. The wipers do not run. Refer to
5 position. Wipers All Modes and Washer
Inoperative.
Turn the wiper switch to the OFF The wipers return to the park position The wipers do not run. Refer to
6 position. at a low speed. Wipers All Modes and Washer
Inoperative.
Refer to the appropriate symptom diagnostic table for the applicable abnormal result.
*
Wipers All Modes and Washer Inoperative

1. Disconnect the windshield wiper motor connector.

a test lamp between CKT 456 (BLU/RED)
1 3. Connect
terminal 3 of the windshield wiper harness connector

to ground.
Repair the open CKT 452 (BLU/RED) between the IP

in
2 fuse block and S234.
1. Disconnect the multifunction switch connector.
3 2. Connect a test lamp from CKT 83 (BRN) terminal 11
of the multifunction switch connector to ground.

Repair the open in CKT 83 (BRN) or CKT 371 (BRN)

4 between the IP fuse block and the multifunction switch.
1998 -
MD-lsuzu
Wipers All Modes and Washer Inoperative (cont'd)

Connect a self-powered test lamp from windshield wiper

5 motor connector CKT 460 (BLK) terminal 6 to ground.
Replace the multifunction switch.

6
Locate and repair the open in CKT 460 (BLK) or CKT 720
7 (BLK) or CKT 550 (BLK) between S325 and G105.
Wipers All Modes Inoperative

1. Disconnect the windshield wiper motor connector.
1 3. Connect a test lamp from CKT 456 (BLU/RED)
terminal 3 of the windshield wiper connector to

ground.
Repair the open in CKT 456 (BLU/RED) between S234

2 and the windshield wiper motor connector.

Connect a self-powered test lamp from windshield wiper
3 motor connector CKT 460 (BLK) terminal 6 to ground.

Repair the open in CKT 460 (BLK) between the windshield
4 wiper motor connector terminal 6 and S325.

1. Connect a test lamp from the windshield wiper motor
connector CKT 459 (BRN/WHT) terminal 5 to ground.
5 Place the windshield wiper switch in the low speed
2.
position.
Replace the windshield wiper motor.
6

Keep the windshield wiper switch in the low speed
position.
7 Backprobe the multifunction switch connector CKT 459
(BRN/WHT) terminal 23 with a test lamp to ground.

Locate and repair the open in CKT 459 (BRN/WHT)
between the multifunction switch and the windshield wiper
8

motor connector.

9
1998 -
MD-lsuzu
Wipers High Mode Inoperative, Low Mode Operates

1. Disconnect the connector at the windshield
wiper motor.
1 3. Connect a test lamp from windshield wiper motor
connector CKT 458 (BRN/YEL) terminal 4 to ground.

4. Place the windshield wiper switch in the high speed
position.
2

Keep the windshield wiper switch in the high speed
position.
3 Backprobe with a test lamp from multifunction switch
connector CKT 458 (BRN/YEL) terminal 24 to ground.

Repair the open in CKT 458 (BRN/YEL) between the
multifunction switch and the windshield wiper motor
4
connector.

5
Wipers Low Mode Inoperative, High Mode Operates

1. Disconnect the connector at the windshield
wiper motor.
1 3. Connect a test lamp from windshield wiper motor

4. Place the windshield wiper switch in the low speed
position.
Replace the windshield wiper switch.
2
Keep the windshield wiper switch in the low speed

position.
3 Backprobe with a test lamp from multifunction switch

Is the repair complete? Go to Step 4 Go to Step 5
Repair the open in CKT 459 (BRN/WHT) between the
multifunction switch and the windshield wiper motor
4
connector.

5
1998 -
MD-ISUZU
Wipers Always On
1. Place the windshield wiper switch in the OFF

position.
1 3. Disconnect the connector at the windshield
wiper motor.
4. Connect a test lamp from the windshield wiper motor


2

Did the test tamp light? Go to Step 3 Go to Step 4

Repair the short to voltage on CKT 459 (BRN/WHT)
between the multifunction switch and the windshield
3
wiper motor.
4

Connect a test lamp from the windshield wiper motor
5 connector CKT 458 (BRN/YEL) terminal 4 to ground.

6


Repair the short to voltage on CKT 458 (BRN/YEL)
7
wiper motor.
8

Connect test lamp from the windshield wiper motor
a
9 connector CKT 457 (BLU/WHT) terminal 2 to ground.

10
Is the repair complete? Go to Step 11

11

Locate and repair the short to voltage on CKT 457
(BLU/WHT) between the multifunction switch and the
12
windshield wiper motor.


13
1998 -
MD-lsuzu
Washers Inoperative
1. Disconnect the connector at the windshield washer
pump motor.
1 2. Connect a test lamp from the windshield washer
pump motor connector CKT 6 (BLU/RED) terminal 1

to ground.
Did the test lamp light? Go toStep 3 Go to Step 2
Repair the open in CKT 6 (BLU/RED) between S234 and

2 the windshield washer pump motor connector.

1. Connect aself-powered test lamp from the
windshield washer pump motor connector CKT 7
3 (BLU/ORN) terminal 2 to ground.
2. Press and hold the WASH switch.

Replace the windshield washer pump motor.
4

1. Backprobe from the multifunction switch connector
terminal 12 to chassis ground with a self-powered
5 test lamp.
2. Press and hold the WASH switch.

Repair the open in CKT 453 (BLU/ORN) between the

multifunction switch and the windshield washer pump
6
motor connector.
7
Washers Always On
1. Disconnect the connector at the windshield washer
pump motor.
1 2. Connect a self-powered test lamp from the
windshield washer pump motor connector CKT 7

(BLU/ORN) terminal 2 to ground.
Replace the windshield washer pump motor.

2
Keep the self-powered test lamp connected.

3 Disconnect the multifunction switch.

Repair the short to ground in CKT 453 (BLU/ORN)
4
-

washer pump motor connector.


5
1998 -
MD-lsuzu
Wiper Arm Tip Pressure Check, Blade

Element Check
If the wipers miss or shudder when wiping the
windshield and the windshield wipers and wiper
inserts are clean, check the wiper arm pressure. If
the wiper arms are not within specifications, replace
the wiper arms. Refer to Wiper Arm Replacement.
Complete the following steps in order to check the
wiper arm pressure:
1. Position the wiper arm in the center of the
windshield.
2. Attach a tension scale at the end of the
wiper arm.
3. While pulling on the scale, lift the wiper arm
approximately 13 mm (0.5 in) above of the
windshield.
4. Measure the wiper arm pressure. Ensure that
the wiper arm pressure is between 7.8-9.5 N
(28-34 oz).
Blade Insert Set Check

Remove the wiper blade assemblies from the wiper
arms. Look down the length of the blade insert. The
rubber insert that contacts the glass must be on the
center line of the blade or no more than 15 degrees.
Replace the insert if necessary.
Repair Instructions
Washer Pump/Reservoir Replacement
Removal Procedure
1. Disconnect the negative battery cable.
2. Raise and support the hood.
3. Remove the electrical connector from the
washer pump motor.
Important: Prior to removing the hoses from
the solvent container or the pump, position an
adequate container in order to catch the fluid.
4. Remove the hoses from the washer pump
motor and the solvent container.
5. Remove the bolts and solvent container from
the vehicle.
215294
1998 -
MD-tsuzu
Body and Accessories Entertainment 8-131
Speaker Noise -
General (cont'd)
1. Disconnect the radio antenna lead-in wire at
the radio.
2. Connect a pre-zeroed ohmmeter between the coax

(outer) conductor of the radio antenna lead in wire
3 0.150
and ground.
3. Measure the resistance.
Does the resistance measure less than the
specified value? Go to Step 5 Go to Step 4
Locate and repair the open or high resistance condition in

4 the antenna ground circuit. -
Is the reception condition resolved? System OK

Wiggle the antenna mast and the lead-in wire while
monitoring the ohmmeter for intermittent opens.
5 0.15ft
Does the power antenna resistance to ground remain less
than the specified value? Go to Step 7 Go to Step 6
Locate and repair the intermittent open or high resistance
6 condition in the antenna ground circuit.
Is the reception condition resolved? System OK Go to Step 7
Connect a pre-zeroed ohmmeter between the signal (inner)

2 ft (RG-58 or
conductor of the radio antenna lead-in wire and the
RG-59) or 3.5 ft
7 antenna mast.
(RG-62 or
Does the antenna lead-in wire signal resistance measure RQ-62M)
less than the specified value? Go to Step 9 Go to Step 8
Locate and repair the open or high resistance condition in

8 the antenna lead-in wire. -
Is the reception condition resolved? System OK
Wiggle the antenna mast and the lead-in wire while 2 ft (RG-58 or
monitoring the ohmmeter for intermittent opens. RG-59) or 3.5 ft
9
Does the antenna lead-in wire signal resistance remain (RG-62 or
less than the specified value? RG-62M) Go to Step 11 Go to Step 10
Locate and repair the intermittent open or high resistance

10 condition in the antenna lead-in wire.
Is the reception condition resolved? System OK Go to Step 11
1. Reconnect the antenna lead-in wire to the radio. Go to Use and

Construction of a
11
Noise Sniffer in
3. Play the radio. Antenna
Is the reception condition resolved? System OK Diagnostic Check
1998 -
MD-lsuzu
8-132 Entertainment Body and Accessories
-5
T
209119
Legend
(1) Negative Battery Cable (5) Body
(2) Coaxial Radio Connector Outer Conductor (6) Chassis Ground
(3) Antenna Mast (7) Coaxial Radio Connector Inner Conductor
(4) Antenna Base
Lead-in Cable Resistance Values Antenna System Resistance Values

DMM Probes At Coaxial Ohmeter Probes At The Following Resistance
Radio Conductor Inner Pair of Points: Measured
Connector And The Negative Coax Outer
Following Points: Resistance Measured Less Than 0.15 Q
Battery Cable Conductor
Antenna Mast Less Than 1.0 Q
Negative
Antenna Base Less Than 0.150
Coaxial Radio Connector Battery Cable
Infinite
Outer Connector
Coax Outer
Antenna Base Less Than 0.15Q
Chassis Ground Infinite Conductor
Negative Coax Inner
Infinite
Battery Cable Conductor
Coax Outer Coax Inner Infinite
Conductor Conductor
Coax Outer
Antenna Mast Infinite
Conductor
Negative
Antenna Mast Infinite
Battery Cable
1998 -
MD-lsuzu
Symptom Diagnostic Test Procedure
Antenna Diagnostic Check


2. Disconnect the antenna lead-in connector at the
radio receiver.
Notice: Before measuring the resistance of the

antenna, remove the negative (-) battery cable and
Less than
1 "zero" the meter before taking measurements. When
checking resistance, cautiously wiggle the lead-in tip 0.15ft
and cable. The readings below should always be
obtained. If not, some portions of the lead-in is
intermittent and the lead-in should be replaced.
3. Using a DMM, measure the resistance between the
coax radio connector outer conductor and the

negative battery cable.
Is the resistance within the specified range? Go to Step 2 Go to Step 5
1. Grasp the antenna mast.
2
2. While observing the DMM, wiggle the antenna.

Does the DMM indicate intermittent continuity? Go to Step 5 Go to Step 3

Notice: Before measuring the resistance of the antenna,
remove the negative (-) battery cable and "zero" the meter
before taking measurements. When checking resistance,
cautiously wiggle the lead-in tip and cable. The readings
below should always be obtained. If not, some portions of
the lead-in is intermittent and the lead-in should be Less than
3
replaced. 0.15ft
Use a DMM and measure the resistance between the
radio coaxial lead-in connector inner conductor and

antenna mast.
Is the resistance within the specified range? Go to Step 4 Go to Step 6
While observing the DMM, wiggle the coaxial wire. Go to Speaker
Noise General
Does the DMM indicate intermittent continuity?
-
General
Go to Step 6 Radio Noise
1. Check the base of the antenna for a good

connection to the body ground.
2. Check the coaxial cable interconnects for a poor

connection or corrosion.
5
3. Check the ground connection from the negative Go to Speaker

battery cable to the body.
Noise General
-
4. Repair the antenna ground circuit as necessary. General

Is the repair complete? System OK Radio Noise
1. Check the coax cable interconnects for a poor

connection or corrosion.
2. Repair or replace the antenna coaxial circuit as
6 necessary.
3. Perform the General Radio Noise diagnostic

procedure.
1998 -
MD-lsuzu
Use And Construction Of A Noise "Sniffer" 3. Plug the sniffer into the radio antenna socket.
Use the noise sniffer along with the radio in
the Important: Do not touch the probe portion bare
vehicle in order to locate "hot spots" that generate conductor of the wire (3).
radio noise interference. Find these "hot spots" in
4. Use the section of probe portion of the wire (3)
the harnesses, the upper part of the instrument in order to search for hot spots while listening
panel, and between the hood and the windshield. to the complaint noise on the radio.
Construct the sniffer by doing the following steps: higher volume.
5. Turn the radio to a
J
-3
209123
209125
1. Find an old, long piece of antenna lead-in (4) 6. Check for noise (1) on a wire (2) by placing the
from a mast or power antenna. sniffer (3) parallel to the wire.
2. Strip 25 mm (2 in) of the insulation (1) from the
center conductor wire (2).
Speakers Inoperative -
One or More (Left Front Speaker)
1. Disconnect the connector at the left front radio
speaker.
Go to left front
2. Connect an ohmmeter between left front radio
1 4-15 a speaker
speaker terminal A and terminal B.
Replacement in
3. Measure the resistance. Speaker
Does the resistance measure within the specified range? Go to Step 2 Replacement.
1. Ensure that the speaker and connector terminals are

not damaged or corroded.
2. Reconnect the connector at the left front radio

2 speaker.
3. Place the ignition switch in the ACCY position.

4. Turn the radio on.
Does the speaker operate properly with clear sound? Go to Step 3 Go to Step 4
1998 -
MO-ISUZU
One or More (Left Front Speaker) (cont'd)
Repair the left front radio speaker connector as necessary.
3
Is the speaker malfunction resolved? System OK Go to Step 4
1. Disconnect the connector at the left front radio

speaker.
2. Disconnect the connector at the radio.
4 3. Verify that no voltage is present on CKT 357 (BLU).
4. Connect a self-powered test lamp between radio

connector terminal 12 for CKT 357 (BLU) and
ground.
1. Locate and repair the short to ground on CKT 357

(BLU) between the radio and the left front radio
5 speaker.
2. Test the speaker performance. Go to Radio

Has the short circuit damaged the radio speaker's output? Replacement Go to Step 6
1. Ensure that no voltage is present on CKT 358

(BLU/WHT).
a self-powered test lamp between radio
6 2. Connect
connector terminal 5 for CKT 358 (BLU/WHT) and

ground.

(BLU/WHT) between the radio and the left front radio
7 speaker.

1. Reconnect the connector at the left front radio

speaker.
2. Connect an ohmmeter between radio connector

8 terminal 5 for CKT 358 (BLU/WHT) and terminal 12 4-15 n
for CKT 357 (BLU).
3. Measure the resistance. Go to Radio

Does the resistance measure within the specified range? Replacement Go to Step 9
Locate and repair the following conditions in CKT 357

(BLU) or CKT 358 (BLU/WHT) between the radio and the
left front radio speaker:
9 1. The open circuit
2. The pinched lead wire

3. The high contact resistance
Is the speaker malfunction resolved? System OK
1998 -
MD-lsuzu
One or More (Right Front Speaker)
1. Disconnect the connector at the right front radio

speaker.
Go to right front
2. Connect an ohmmeter between right front radio
1 4-150 speaker
speaker terminal A and terminal B.
Replacement in
3. Measure the resistance. Speaker
Does the resistance measure within the specified range? Go to Step 2 Replacement
1. Ensure that the speaker and connector terminals are

not damaged or corroded.
2. Reconnect the connector at the right front radio

2 speaker.
3. Place the ignition switch in the ACCY position.
4. Turn the radio on.

Does the speaker operate properly with clear sound? Go to Step 3 Go to Step 4
Repair the right front radio speaker connector as
3 necessary.
Is the speaker malfunction resolved? System OK Go to Step 4
1. Disconnect the connector at the right front radio

speaker.
2. Disconnect the connector at the radio.
4 3. Verify that no voltage is present on CKT 155 (GRN)
and CKT 355 (GRN).

4. Connect a self-powered test lamp between radio
connector terminal 13 for CKT 355 (GRN) and ground.
1. Locate and repair the short to ground on

CKT 155 (GRN) and CKT 355 (GRN) between the
5 radio and the right front radio speaker.

1. Ensure that no voltage is present on CKT 156

(GRN/WHT) and CKT 356 (GRN/WHT).
6 2. Connect a self-powered test lamp between radio
connector terminal 6 for CKT 156 (GRN/WHT) and

CKT 356 (GRN/WHT) and ground.
(GRN/WHT) and CKT 356 (GRN/WHT) between the
7 radio and the right front radio speaker.

1998 -
MD-lsuzu
One or More (Right Front Speaker) (cont'd)
1. Reconnect the connector at the right front radio
speaker.
2. Connect an ohmmeter between radio connector
8 terminal 13 for CKT 355 (GRN/WHT) and terminal 6 4-150
for CKT 356 (GRN).
3. Measure the resistance. Go to Radio

Does the resistance measure within the specified range? Replacement Go to Step 9
Locate and repair the following conditions in CKT 355
(GRN) or CKT 356 (GRN/WHT) between the radio and the
right front radio speaker:
9 1. The open circuit
2. The pinched lead wire

3. The high contact resistance
Is the speaker malfunction resolved? System OK
Repair Instructions
Radio Replacement
Removal Procedure
1. Remove the lower instrument panel trim.
2. Remove the radio retaining screws.
3. Remove the antenna cable.
4. Remove the electrical connectors.
5. Remove the radio brackets.
214688
6. Remove the radio.
214886
1998 -
MD-lsuzu
138 Entertainment Body and Accessories
1. Install the radio.
214686
2. Install the radio brackets.

3. Install the electrical connectors.
4. Install the antenna cable.
5. Install the radio retaining screws.
6. Install the lower instrument panel trim.
214688
Cleaning Tape Head and Capstan,

Cassette Cleaning
Tape Player and Cassette Care
For the best operation of the cassette tape player,
do not use cassette tapes that are longer than
90 minutes in playback time (45 minutes or longer
per side). Cassette tapes longer than 90 minutes
may cause the tape to slip or jam.
Tape Head and Capstan Cleaning

There are two parts that are cleaned on a tape
player: the head and the capstan. Since they can be
reached through the tape door, leave the tape player
in the vehicle. This service should be performed
every 50 hours of operation.
In order to clean the head and capstan, use a cotton
swab dipped in ordinary rubbing alcohol, or use a
cleaning cassette.
65835
1998 -
MD-ISUZU
As an alternate way to clean the head and capstan,

a cleaning cassette may be purchased. Follow the
instructions included with the kit to clean the tape
player.
Do not contact the tape head with magnetized tools.
If the head becomes magnetized, every cassette
played in the player will be degraded.
No service is performed on the tapes. Warranty of
these tapes is handled by the cassette manufacturer,
not by the dealer. Any test tape used by the dealer
should be stored in the test tape container in order
to keep the tape clean. Store cassettes away from
extreme heat or direct sunlight.
Fixed Antenna Mast Replacement

Removal Procedure
2. Remove the upper instrument panel pad.
3. Remove the radio.
4. Remove the cable from the back of the radio.
5. Remove the retaining clips.
6. Remove the two screws from the antenna base
on the cab.
214691
7. Remove the antenna from the cab.
214692
1998 -
MD-lsuzu
1. Install the antenna to the cab.
2. Install the antenna base screws.
214692
3. Install the cable to the back of the radio.

4. Install the retaining clips.
5. Install the radio.
6. Install the upper instrument panel pad.
214691
Speaker Replacement
Removal Procedure
1. Remove the speaker grille.
2. Remove the nuts.
3. Remove the speaker.
4. Remove the electrical connectors, as necessary.
214690
1998 -
MD-lsuzu
1. Install the electrical connectors, as necessary.
2. Install the speaker.

3. Install the nuts.
4. Install the speaker grille.
214690

Radio/Audio System Description
The radio is mounted under the climate controls on
the instrument panel. The available radio systems
are as follows:
1. UM7- AM/FM stereo, seek and scan, clock
2. UM6- AM/FM stereo, seek and scan,
auto-reverse cassette, clock
Radio/Audio System Operation

AM/FM Stereo Radio (UM7 or UM6)
On/Volume/Balance Knob
Press the on/volume/balance knob in order to turn
the radio on and off. Turn the knob clockwise in
order to increase the volume and counter clockwise
in order to decrease the volume. The ignition lock
cylinder must be in the ACCESSORY or the RUN
position for the radio to operate.
Finding a Station
Band: In order to tune the radio, push the DISP
button and select the band. Pressing this button
alternately selects either the AM or FM band. The
selected band will be on the display.
Tuning the Buttons: Press the button with the
upward arrow in order to increase the frequency.
Press the button with the downward arrow in order
to decrease the frequency.
In order to use automatic tuning, push one of the
tuning buttons for a half a second or longer.
The frequency display will stop automatically when a
live frequency is detected.

In order to tune stations manually, push one of the
buttons for less than half a second.
Scan: Press this button in order to listen to the next
radio station for a few seconds. The radio will scan
stations until the scan button is pressed during the
five seconds that a station is being reviewed.
1998 -
hID-lsuzu
Preset Buttons: The six numbered preset buttons Set the desired time the same way as you set
let you return to your favorite stations. You can set the clock.
up to 12 stations (6 AM, 6FM). Complete the When the set time comes, the radio is switched on
following steps to preset a station:
and remains on for one hour.
Tune in the desired station.
The wake up feature is activated only once and the
Press one of the preset buttons for two seconds or
alarm set status will be returned automatically when
longer.
one hour is over.
Whenever you press that numbered button for less
To cancel wake-up when it is activated, press the
than two seconds, the station you set will return.
alarm button.
DISP Button: With each press of this button, the
display alternates between the time, alarm status, Setting the Tone: Turn the tone knob clockwise in
and radio frequency. The display automatically order to emphasize the treble and counterclockwise
returns to the clock mode after a few seconds when to emphasize the bass.
the radio is on. Setting the Clock: Press and hold down the AM/FM
Setting the Tone: Turn the tone knob clockwise in button. Press the downward arrow button in order to
order to emphasize the treble. Turn the tone knob advance the hours. Press upward arrow button in
counterclockwise in order to emphasize the bass. order to advance the minutes.
Adjusting the Speakers: Pull out the
power/volume/balance knob. Turn the knob to the
Playing a Cassette Tape
right or left, depending on which speakers you want The tape player is built to work best with tapes that
the sound to come through. are 30 to 45 minutes long on each side. Tapes
Using the Timer: The timer in your radio can be longer than that are so thin they may not work well
in this player.
used to set a time from 15 minutes to three hours.
An alarm sounds when the time expires. Once the tape is playing, use the knobs for volume,
In order to set the timer, press the timer button. The tone and balance, just as you do for radio operation.
timer symbol and 0:00 will be lighted on the display. FF/Rew Buttons: Press the button with the arrows
With each press of the button, the time increases. in the same direction of tape play (as indicated on
When the time expires, an alarm will sound for two the display) in order to rapidly advance the tape.
minutes. When the timer is set back to 0:00, the
Press the other button in order to rewind the tape.
timer symbol will disappear from the display.
In order to stop fast forwarding or rewinding, press
Using the Alarm: The alarm in the radio can be
used to activate an alarm at a desired time. the other button lightly.
In order to set the timer, press the DISP button to Press both fast forward buttons at the same time in
switch the display to ALARM. Press the alarm button order to switch the tape sides. An arrow will light on
while the alarm symbol is flashing. An A will the display in order to indicate the tape playing
illuminate in the display. direction.
After setting an alarm time the same way as setting Eject Button: Press this button in order to remove
a clock, wait until the current time is indicated. Then, the tape or stop the tape and play the radio.
press the alarm button. The alarm symbol will
appear in the display. Once set, the alarm will sound Radio/Audio System Circuit Description
at the same time each day.
In order to make sure of the alarm time, press the Radio
display button. In order to disconnect the alarm, Circuit breaker #7 makes voltage available at all
press the alarm button again. times to the radio through CKT 350 (ORN). This
Setting the Wake-up Timer: The wake up timer is voltage provides power to the radio memory storage
used to turn the radio on at a specific time without for time and station presets. Operating power is
the key in the ignition. available to the radio from circuit breaker #2 through
Press the DISP button. While the alarm symbol CKT 352 (YEL) when the ignition switch is in the
flashes, press the alarm button so that the display RUN position or the ACCY position. CKT 354 (BLK)
shows U. grounds the radio at joint connector 1, (lower).
1998 -
MD-lsuzu
Body and Accessories Wiring Systems 8-143
Wiring Systems
Specifications

Specification
Air Horn Mounting Bolt 9N.m 80 Ib in
Electric Horn Mounting Nut 17N.m 13lbft
Lanyard to Roof Panel Bolt 2N.m 18lbin
Diagnostic Information and common across all vehicle platforms. Cells are
organized by subsystems with most containing a
Procedures circuit schematic and the associated text. For
Where to Find Electrical Schematics example, the cruise control schematic will be located
in the cruise control subsection and the schematic
Because more than one electrical system is located title will begin with cell 34.
ineach subsection, each electrical system's
Some subsections may have more than one circuit
schematics are further broken down into operating
schematic such as Power Distribution, Interior Lights
systems, or cells. Each set of electrical system
and Air Conditioning.
schematics will have a cell number that remains
Electrical Schematic Locations

Cell No. System Name Section Subsection
10 Power Distribution Schematics Body and Accessories Wiring Systems
Ground Distribution
14 Body and Accessories Wiring Systems
Schematics
Retained Accessory Power
15 Body and Accessories Retained Accessory Power
Schematics
17 Auxiliary Battery Schematics Body and Accessories Wiring Systems
18 Upfitter Provision Schematics Body and Accessories Wiring systems
Cigar Lighter/Auxiliary Outlet

Schematics
20 Engine Controls Schematics Engine Engine Controls
Starting and Charging

30 Engine Engine Electrical
Schematics
31 Cooling fan Schematics Engine Engine Cooling
32 Radiator Shutter Schematics Engine Engine Cooling
Engine Exhaust Brake

33 Brakes Engine Exhaust
Schematics
34 Cruise Control Schematics Body and Accessories Cruise Control
Manual Transmission
35 Transmission Transaxle Manual Transmission
Schematics
Inter-Axle Differential Lock
36 Driveline/Axle Rear Axle Controls
Schematics
Two Speed Rear Axle
37 Driveline/Axle Rear Axle Controls
Schematics
Transfer Case Control
38 Driveline/Axle Transfer Case
Schematics
Automatic Transmission Automatic Transmission or
39 Transmission/Transaxle
Controls Schematics Automatic Transaxle
40 Horn Schematics Body and Accessories Horns
1998 -
MD-lsuzu
8-144 Wiring Systems Body and Accessories
Electrical Schematic Locations (cont'd)

Brake Warning System Hydraulic Brakes or
41 Brakes
Schematics Air Brakes
42 ALC Suspension Schematics Suspension Automatic Level Control

Road Sensing Suspension -
Suspension Controls RSS Real Time Dampening

43 Suspension -
Schematics RTD Air Suspension
ABS Schematics ABS/TCS

44 Brakes ABS Traction Control
Schematics
45 Steering Control Schematics Steering Variable Effort Steering
Park Brake System

46 Brakes Park Brakes
Schematics
SIR Schematics SRS
47 Restraints SIR
Schematics
48 Tire Pressure Monitor System Suspension Tire Pressure Monitor
Tilt/Telescoping Steering Steering Wheel and
49 Steering
Column Schematics Column Tilt
Data Link Connector (DLC)

Schematics
Body Control Module
51 Body and Accessories Body Control System
Schematics
Door Control Module Body and Accessories

55 Doors
Schematics
Brake Booster Pump
57 Brakes Hydraulic Brakes
Schematics
58 Air Brake System Schematics Brakes Air Brakes
Heater Blower Controls Heater and Ventilation

60 HVAC
Schematics (Non-A/C)
61 Defogger Schematics Body and Accessories Stationary Windows
Heated Windshield
62 Body and Accessories Stationary Windows
Schematics
HVAC Blower Controls HVAC Systems with
63 HVAC
Schematics A/C Manual
HVAC Compressor Controls
Schematics HVAC HVAC Systems with
64 HVAC
Compressor/Condensor Fan A/C Manual
Controls Schematics
HVAC Air Delivery Controls HVAC Systems with
65 HVAC
Schematics A/C Manual
HVAC Systems with
HVAC Blower Controls
66 HVAC A/C-Automatic (Includes
Schematics
Electronic and Dual Zone)
HVAC Compressor Controls
HVAC Systems with A/C
Schematics HVAC
67 HVAC Automatic (Includes Electronic
Compressor/Condensor Fan
and Dual Zone)
Controls Schematics
HVAC Systems with
HVAC Air Delivery Controls
68 HVAC A/C-Automatic (Includes
Schematics
Electronic and Dual Zone)
Collision Avoidance
70 Body and Accessories Collision Avoidance
Schematic
Instrument Panel, Gauges
76 Audible Warnings Schematics Body and Accessories
and Console
1998 -
MD-lsuzu

Backup Alarm System
79 Body and Accessories Backup Alarm
Schematics
81
Instrument Cluster: Analog Instrument Panel, Gauges
Schematics and Console
Instrument Cluster: Digital Instrument Panel, Gauges
82 Body and Accessories
83 Head Up Display Schematics Body and Accessories
and Console
85 Navigation System Schematic Body and Accessories
and Console
Driver Information System Instrument Panel, Gauges
86 Body and Accessories
Wiper/Washer System
90 Body and Accessories Wiper/Washer Systems
(Standard) Schematics
Wiper/Washer System (Pulse)

91 Body and Accesspories Wiper/Washer Systems
Schematics
Wiper/Washer System (Rear)
92 Body and Accessories Wiper/Washer Systems
Schematics
Headlamp Washer Body and Accessories
93 Wiper/Washer Systems
Schematics
100 Headlights Schematics Body and Accessories Wiper/Washer Systems
Headlights Twilight
101 Body and Accessories Lighting Systems
Sentinel/DRL Schematics
102 Headlights DRL Schematics Body and Accessories Lighting Systems
103 Fog Lights Schematics Body and Accessories Lighting Systems
104 Headlight Doors Schematics Body and Accessories Lighting Systems

Headlight Leveling
Schematrics
110 Exterior Lights Schematics Body and Accessories Lighting Systems
112 Backup Lights Schematics Body and Accessories Lighting Systems
114 Interior Lights Schematics Body and Accessories Lighting Systems
Interior Lights Dimming

Schematics
120 Power Windows Schematics Body and Accessories Doors
Power Folding Top Body and Accessories
121 Roof
Schematics
122 Power Sunroof Schematics Body and Accessories Roof
130 Door Locks Schematics Body and Accessories Door Locks

132 Keyless Entry Schematics Body and Accessories Keyless Entry
Theft Deterrent System

133 Body and Accessories Theft Deterrent
Schematics
134 Release System Schematics Body and Accessories Body Rear End
135 Pulldown Systems Schematics Body and Accessories Body Rear End
Garage Door Opeener Body and Accessories

136 Garage Door Opener
Schematics
Power Sliding Door (PSD) Body and Accessories
137 Doors
Schematics
Steering Wheel and Column
138 BTSI Schematics Steering Standard Steering Wheel and
Column Tilt
1998 -
MD-lsuzu

Steering Wheel and Column
139 Column/Ignition Steering Standard Steering Wheel and
Column Tilt
140 Power Seat Schematics Body and Accessories Seats
141 Memory Seats Schematics Body and Accessories seats
142 Lumbar Support Schematics Body and Accessories Seats
143 Heated Seats Schematics Body and Accessories Seats
146 Power Seat Schematics Restraints Seat Belts
147 Outside Mirrors Schematics Body and Accessories Doors
148 Automatic Day-Night Mirror Body and Accessories Stationary Windows
Radio/Audio Systems
150 Body and Accessories Entertainment
Schematics
151 Power Antenna Schematics Body and Accessories Entertainment
Steering Wheel Controls
152 Body and Accessories Entertainment
Schematics
Cellular Telephone
153 Body and Accessories Cellular Communications
Schematics
154 On Star Schematics Body and Accessories Cellular Communications
How to Use Electrical Diagnosis How to Use Electrical Schematics

Electrical Diagnosis contains the following types of The wiring schematic is the cornerstone of electrical
diagnostic information. Using these elements together diagnosis. Schematics break the entire electrical
makes the electrical diagnosis of the various vehicle system into individual circuits, showing the electrical
systems faster and easier: current paths when a circuit is operating properly.
Schematic Reference Table, refer to How to Wiring which is not part of the circuit of interest is
Use Schematic Reference Tables referenced to another page where the circuit is
shown complete. Schematics use a top (power) to

Schematic Icon Table, refer to How to Use
bottom (ground) sequence to present electrical
Schematic Icon Tables
information.
Electrical Schematics, refer to Where to Find
Electrical Schematics Important: The schematic does not represent the
components and wiring as they physically appear on

Component Location Table, refer to How to Use the vehicle. For example, a 4-foot length of wire is
Component Location Tables treated no differently in a schematic from one which

Component Location Views, refer to How to is only a few inches long.
Use Connector End Views
When diagnosing a horn problem use the service
Connector End Views, refer to How to Use information located in the Horns (cell 40) service
Connector End Views category. The following schematic is a typical
System Check(s), refer to How to Use example of a schematic with its supporting text.
Diagnostic System Checks
Diagnostic Tables, refer to How to Use
Diagnostic Tables
Circuit Description, refer to How to Use Circuit
Descriptions
1998 -
MD-lsuzu
|HotAtAIITimes|
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How to Use Schematic Reference Tables The reference to the component view
The schematic reference table is used when a circuit The reference to the connector end view
(if applicable)
continues into another electrical system's schematic.
The schematic reference table matches all
Name
references made on schematics to the appropriate
service category type number and service category The name cells provide the name of the components
where the schematic's continuation is shown. that are used on the schematic(s). If a connector is
listed the number of cavities are also provided. This
How to Use Schematic Icon Tables represents the total number of cavities in the
The schematic icon table shows all icons on connector regardless of how many connectors are
schematic with their definition or references. actually used.
How to Use Component Location Tables Location

The component location table shows a list of all the The location cell providesa written location of where
electrical components within a systems electrical the component is in the vehicle with respect to
schematics. The table consists of the following vehicle landmarks. Nearly all of the following
information within a system's electrical schematic: information shown on a schematic can be pinpointed
All components visually using the component location view
illustrations:

Grounds

Pass-through grommets
Components
Splices
Connectors
The table consists of 4 columns which describe the
Grounds
following information:
Splices
The component name
The component location
1998 -
MD-lsuzu
48 Wiring Systems Body and Accessories
;ator View How to Use Component Location Views

3 column contains the reference to the Component location views are line illustrations that
iropriate component view. The reference contains indicate all of the vehicle's electrical components
location within the subsection and the section. within each electrical system.
er to How to Use Component Location Views. Below is an example of a typical component view.
nnector End View
> column contains the reference to the
iropriate connector end view. The reference
tains the location within the subsection and the
tion. Refer to How to Use Connector End Views.
Hood Ajar Switch, Horns, and S114
154362
lend
(1) Hood Ajar Switch (Export) (3) RH Horn A Note
(2) S114 (4) RH Horn F Note
1998 -
MD-lsuzu
How to Use Connector End Views

Connector end views show the cavity or terminal
locations for all the related 2pin or larger
connectors shown in the system schematic(s). The
drawings show the connector's face as seen after
the harness connector has been disconnected from a
component or mating connector. Unused cavities are
left blank in the table.
In addition, the color and part number of the
connector body is provided along with the
family/series name.
Below is an example of a typical connector end view.
RH Horn A Note
35437

12052644
Connector Part
Information
2 Way F Metri-Pack
150 Series Sealed (GRY)
Circuit
A BLK 250 Ground
B DKGRN 29 Horn Feed
How to Use Diagnostic System Checks

The system check gives a summary of how the
system operates and what actions occur. This is
especially important when working on a new system.
The system check will help identify symptoms, lead
to diagnosis and confirm normal operation of the
system after repair.
Horn System Check

Step Action Normal Result(s) Abnormal Result(s)*
Press horn switch. All Horns sound with good horn tone. Horns Inoperative
1
One Horn Inoperative

Poor Horn Tone
2 Release horn switch. Horns do not sound. Horns Always On
*
Refer to the appropriate symptom diagnostic table for the applicable abnormal result.
1998 -
MD-lsuzu
How to Use Diagnostic Tables based, to assist you in locating the condition as fast
Diagnostic tables provide a procedure that will help as possible. Diagnostic tables should exist for all
possible (realistic) symptoms and diagnostic trouble
you locate the condition in a circuit that is causing a
codes (DTCs).
malfunction. All diagnostic procedures are symptom
Horns Inoperative
DEFINIT ION: Horns will not sound when horn button is pressed.
1
Was the Diagnostic System Check performed?
Go to Horns
Go to Step 2 System Check
1. Turn ignition switch to OFF.

2. Remove the horn relay.
2 3. Connect a fused jumper across the horn relay
terminals 30 and 87.

Do the horns sound? Go to Step 3 Go to Step 6
Connect a test lamp between the horn relay terminals 85

3 and ground.
Go to Power
Does the test lamp light? Go to Step 4 Distribution
1. Connect a test lamp between the horn relay

terminal 86 and battery (B+).
4
2.Press and hold the horn switch.

Replace the horn relay. Go to Horns
5
Is the repair completed? System Check

Connect a test lamp between the underhood junction block
6 terminal A12 or B12 (CKT 29) and ground.
Replace the underhood junction block, refer to underhood

7 junction block replacement.
Go to Horns
Is repair completed? System Check

Connect a test lamp between the Ground Splice Pack
8 G104 (CKT 250) and battery (B+).

Replace horns. Go to Horns
9

Inspect G104 ground, if OK replace Ground Splice
10 Pack G104.
Go to Horns

1. Disconnect the underhood junction block
connector C2.
11 2. Connect a test lamp between the underhood junction
block terminal D1 and battery (B+).

3. Press and hold the horn switch.
1. Disconnect the Dash Integration Module (DIM).

2. Connect a test lamp between the underhood junction
12 block terminal D1 and battery (B+).
3. Press and hold the hom switch.

Replace the Dash Integration Module (DIM), refer to DIM
13 replacement.
Go to Horns
1998 -
MD-lsuzu
Horns Inoperative (cont'd)

1. Disconnect C202.
2. Connect a test lamp between connector C202

terminal B12 of the steering column side and
14
battery (B+).
3.Press and hold the horn switch.

Repair short to ground in CKT 28 (BLK). Go to Horns
15
Repair open in CKT 28 in the steering column. Go to Horns

16
How to Use Circuit Descriptions Electrical Symbols (cont'd)

The circuit description describes how the system Symbol Description
works electrically. It details how power, ground,
inputs, and outputs are supplied to the system's On-Board Diagnostic
related components. The circuit description also (OBD II) Icon.
explains the communication and interaction of all This icon is used to alert the
components that affect the operation of the system. technician that the circuit is
Battery positive voltage is applied at all times to the essential for proper OBD II
horn relay terminals 85 and 30. Pressing the horn emission controls circuit
switch grounds the horn relay coil on CKT 28 (BLK). operation. Any circuit which,
The relay coil can also be grounded on CKT 28 if it fails, causes the
(BLK) by the Dash Integration Module (DIM). The malfunction indicator lamp
horn relay applies battery positive voltage to the (MIL ) to turn on, is identified
horns on CKT 29 (DK GRN) when energized. The 106632
as an OBD II circuit.
horns sound until the horn switch is released or the
DIM signal is gone.
Electrical Symbols Important Icon
Symbol Description A This icon is used to.alert the

technician that there is
additional information that
Electrostatic Sensitive will aid in servicing a
Discharge (ESD) Icon. system.
This icon is used to alert the
technician that the system
A^ contains ESD sensitive 106633
components that require

certain precautions before
servicing. Refer to Handling
ESD Sensitive Parts Notice
in Cautions and Notices. Voltage Indicator Boxes.
106629
These boxes are used on
Supplemental Inflatable schematics to indicate when
Restraint (SIR) or voltage is present at a fuse.
Supplemental Restraint
System (SRS) Icon.
This icon is used to alert
the technician that the 106635
system contains SIR/SRS

components that require
certain precautions before
servicing. Refer to SIR
Handling Caution in General
106630 Information.
1998 -
MD-lsuzu
-152 Wiring Systems Body and Accessories
Electrical Symbols (cont'd) Electrical Symbols (cont'd)

Symbol Description Symbol Description
Partial Component.
When component is
a
represented in a dashed Fusible Link

box, the component or it's
wiring is not shown in it's
entirety.
106637 106644
Entire Component.
When a component is
Connector Attached to
represented in a solid box
Component
the component or it's wiring
is shown in it's entirety.
106641 106645
Fuse Pigtail Connector
106643 106646
Bolt On or Screw On Eyelet

Circuit Breaker
Terminal
106642 106647
1998 -
MD-lsuzu
dy and Accessories Wiring Systems 8-153

12lci00
T Inline Harness Connector Case Ground
L*J
106648 106652
>S100
Splice

1
(b Single Filaments Light Bulb
T
106649 106653
Jl Jl
SP100 ft ?)
Pass Through The Grommet \;T'J Double Filament Light Bulb
T
106650 106654
Jl
JL
Chassis Ground
^^ (D Light Emitting Diodes
'G100
y^
106651 106655
-
MD-lsuzu

1
Capacitor Variable Resistor
106656 106659
T Battery Position Sensor
106657 106661
^ Variable Battery I/O Resistors
106660 106662
; 7
Resistor -l I I/O Switches
106658 106663
1998 -
MD-lsuzu

+ Diode
III Solenoid
106664 106668
1
T Crystal Coil
106665 106669
Heating Elements
^ Antenna
106666 106670
^ .T J" ^
<$ Motor Shield

r.-.-A
106667 106671
998 -
MD-lsuzu
Electrical Symbols (cont'd) Read the Electrical Schematic

Study the schematic and read the Circuit Description
Symbol Description text to gain an understanding of how the circuit
should work. Check circuits that share wiring with the
problem circuit. (Shared circuits are shown on Power
Distribution, Ground Distribution, Fuse Block Detail
pages.) Try to operate the shared circuits. If the
} shared circuits work, then the shared wiring is OK.
The cause must be within the wiring used only by
-T Switches
the problem circuit. If several circuits fail at the same
time, chances are the power (fuse) or ground circuit
is faulty.
Find the fault and repair

Narrow down the possible causes.
106672
Use the Troubleshooting Hints.
Make the necessary measurements or checks as
given in the System Diagnosis.
Before replacing a component, check power, signal
and ground wires at the component harness
connector. If the checks and connections are OK,
Single Pole Single Throw
the most probable cause is component failure.
1 Relay
Test the Repair
Repeat the System Check to verify that the fault has
been corrected and that no other faults were induced
during the repair.
106673 Troubleshooting Tools

Electrical troubleshooting requires the use of
common electrical test equipment.
Test Light
A test light is a simple quick way to check a circuit
for voltage. The J 34142-B test light is made up of a
Single Pole Double 12 volt light bulb with a pair of leads attached. After
J^l
v v
Throw Relay grounding one lead, touch the other lead to various
points along the circuit where voltage should be
present. When the bulb goes on, there is voltage at
the point being tested. A J 21008-A self-powered test
light can be used to check for continuity. This tool is
106674 made up of a light bulb, Battery and two leads. If
the leads are touched together, the bulb will go on.
A self-powered test light is used only on an
General Electrical Diagnosis Procedures
unpowered circuit. First remove the fuse which feeds
the circuit you're working on. Select two specific
Basic Knowledge Required points along the circuit through which there should
Without a basic knowledge of electricity, it will be be continuity. Connect one lead of the self-powered
difficult to use the diagnostic procedures contained in test light to each point. If there is continuity, the test
this section. You should understand the basic theory light circuit will be completed and the bulb will go on.
of electricity and know the meaning of voltage Never use a self-powered test light on circuits that
(volts), current (amps) and resistance (ohms). You contain solid state components, since damage to
should understand what happens in a circuit with an these components may result.
open or a shorted wire. You should be able to read Digital Multimeter (DMM)
and understand a wiring diagram. A DMM can be used instead of a test light to check
for voltage. While a test light shows whether or not
The following four-step troubleshooting procedure is
voltage is present, a DMM indicates how much
recommended:
voltage is present.
Check the Problem An increasing number of circuits include solid state
Perform a System Check to determine a symptom. control modules. One example is the Power-train
Don't waste time fixing part of the problem! Do not Control Module (PCM). Voltages in these circuits
begin disassembly or testing until you have narrowed should be tested only with a 10-megohm or higher
down the possible causes. impedance J 39200 Digital Multimeter (DMM). Unless
directed to within the diagnostics, never use a test
light on circuits that contain solid state components,
since damage to these components may result.
1998 -
MO-lsuzu
When testing for voltage or continuity at the Always check for aftermarket accessories (non-OEM)
connection, it is not necessary to separate the two as the first step in diagnosing electrical problems. If
halves of the connector. Unless testing a Weather the vehicle is so equipped, disconnect the system to
Pack or a Metri Pack connector 150 series and verify that these add-on accessories are not the
below, always probe the connector from the back. cause of the problems.
Always check both sides of the connector. An
Some possible causes of vehicle problems related to
accumulation of dirt and corrosion between contact
aftermarket accessories include:
surfaces is sometimes a cause of electrical
problems. A terminal contact checking procedure can

Power feeds connected to points other than the
battery.
be found later in this section.
A Digital Multimeter can also be used instead of a
Antenna location.
self-powered test light to check for circuit continuity.
Transceiver wiring located too close to vehicle
The ohmmeter function on a DMM shows how much electronic modules or wiring.
resistance there is between two points along a
Poor shielding or poor connectors on antenna
circuit. Low resistance means good continuity. feed line.
Circuits which include any solid state control . Check for recent service bulletins detailing
modules, such as the PCM, should be tested only installation guidelines for aftermarket
with a 10-megohm or higher impedance J 39200
accessories.
digital Multimeter.
Probing
When measuring resistance with a DMM, the
After probing, when reconnecting connectors or
vehicle's Battery should be disconnected. This will
replacing terminals, always be sure to reinstall
prevent incorrect readings. DMMs apply such a small
voltage to measure resistance that the presence of Connector Position Assurance (CPA) and Terminal
Position Assurance (TPA).
voltages can upset a resistance reading.
Diodes and solid state components in a circuit can Frontprobe
cause an Digital Multimeter to give a false reading. To
When frontprobing of connectors is required, always
find out if a component is affecting a measurement, use mating

a terminal adapter from the (J 35616-A)
take a reading once, reverse the leads and take a Connector Test Adapter Kit. The use of proper
second reading. If the readings differ, the solid state adapters will ensure that proper terminal contact
integrity is maintained. A terminal contact checking
component is affecting the measurement.
procedure is located later in this section.
Connector Test Adapters
Connector Test Adapter Kit is available for making Backprobe
Only backprobe connector terminals when specifically
tests and measurements at separated connectors.
This kit contains an assortment of probes which called for in diagnostic procedures. Since
backprobing can be a source of damage to
mate with many of the types of terminals you will
connector terminals, extra care must be taken to
see. Avoid using paper clips and other substitutes
since they can damage terminals and cause avoid deforming the terminal, either by forcing the
incorrect measurements. test probe too far into the cavity or by using too
large a test probe.
Fused Jumper Wire
The J 36169 fused jumper is available with small After backprobing any connector, always check for
clamp connectors providing adaptation to most terminal damage. If terminal damage is suspected,
connectors without damage. This fused jumper wire check for proper terminal contact (refer to Checking
is supplied with a 20 A fuse which may not be Terminal Contact, later in this section).
suitable for some circuits. Do not use a fuse with a Testing for Voltage
higher rating than the fuse that protects the circuit a test light to a known good
Connect one lead of
being tested. When using DMM, be sure the voltmeter's
ground. a
Short Finder negative lead is connected to ground.

The J 8681 -A short finder is available to locate Connect the other lead of the test light or voltmeter
hidden shorts to ground. The short finder creates a
a selected test point (connector or terminal).
to
pulsing magnetic field in the shorted circuit and
If the test light illuminates, there is voltage present.
shows you the location of the short through body
trim or sheet metal. When using DMM, note the voltage reading.
a
Notice: A fused jumper may not protect solid state Testing for Continuity
components from being damaged. Remove the fuse to the circuit involved.
Troubleshooting Tests Connect one lead of a self-powered test light or

ohmmeter to one end of the part of the circuit you
Aftermarket Accessories wish to test.
Do not connect aftermarket accessories into SIR
circuits. All such circuits are indicated on circuit Connect the other lead to the other end of the
diagrams with the SIR symbol. circuit.
Do not connect aftermarket accessories into OBD II If the self-powered test light glows, there is
circuits. All such circuits are indicated on circuit continuity. When using an ohmmeter, low or no
diagrams with the OBD II symbol. resistance means good continuity.
1998 -
MD-lsuzu
Testing for Voltage Drop Intermittent and Poor Connections

This test checks for voltage being lost along a wire, Most intermittents are caused by faulty electrical
or through a connection or switch. connections or wiring, although occasionally a
Connect the positive lead of a DMM to the end of sticking relay or solenoid can be a problem. Some
the wire (or to one side of the connection or switch) items to check are:
which is closer to the Battery.
Poor mating of connector halves, or terminals
Connect the negative lead to the other end of the not fully seated in the connector body
(backed out).
wire (or the other side of the connection or switch).
Dirt or corrosion on the terminals. The terminals
Operate the circuit.
must be clean and free of any foreign material
The DMM will show the difference in voltage which could impede proper terminal contact.
between the two points.
Damaged connector body, exposing the
Testing for Short to Ground terminals to moisture and dirt, as well as not
With a Test Light or DMM: maintaining proper terminal orientation with the
1. Remove the blown fuse and disconnect component or mating connector.
the load. Improperly formed or damaged terminals. All
connector terminals in problem circuits should be
2. Connect a test light or voltmeter across the
checked carefully to ensure good contact tension.
fuse terminals (be sure that the fuse is
Use a corresponding mating terminal to check for
powered).
proper tension. Refer to Checking Terminal
3. Beginning near the Fuse Block, wiggle the Contact in this section for the specific procedure.
harness from side to side. Continue this at The J 35616-A Connector Test Adapter Kit must
convenient points (about 6 inches apart) while
be used whenever a diagnostic procedure
watching the test light or DMM.
requests checking or probing a terminal. Using
4. When the test light glows, or the DMM the adapter will ensure that no damage to the
registers, there is a short to ground in the terminal will occur, as well as giving an idea of
wiring near that point. whether contact tension is sufficient. If contact
With a Self-Powered Test Light or Ohmmeter: tension seems incorrect, refer to Checking
Terminal Contact in this section for specifics.
1. Remove the blown fuse and disconnect the
battery and load.
Poor terminal to wire connection. Some
conditions which fall under this description are
2. Connect one lead of a self-powered test light or poor crimps, poor solder joints, crimping over wire
ohmmeter to the fuse terminal on the load side. insulation rather than the wire itself, corrosion in
3. Connect the other lead to a known good the wire to terminal contact area, etc.
ground. Wire insulation which is rubbed through,
4. Beginning near the Fuse Block, wiggle the causing an intermittent short as the bare area
harness from side to side. Continue this at touches other wiring or parts of the vehicle.
convenient points (about 6 inches apart) while Wiring broken inside the insulation. This
watching the self-powered test light or condition could cause a continuity check to
ohmmeter. show a good circuit, but if only one or two
strands of a multi-strand type wire are intact,
5. When the self-powered test light glows, or the
ohmmeter registers, there is a short to ground resistance could be far too high.
in the wiring near that point. To avoid any of the above problems when making
wiring or terminal repairs, always follow the
Fuses Powering Several Loads:
instructions for wiring and terminal repair detailed in
1. Find the schematic in Fuse Block Details, for Wiring Repairs and Connector Repairs.
the fuse that has blown.
2. Open the first connector or switch leading from
Checking Terminal Contact
the fuse to each load. When diagnosing an electrical system that utilizes
Metri-Pack 150/280/480/630 series terminals (refer to
3. Replace the fuse.
the J 38125-A Terminal Repair Kit or the J 38125-4
If the fuse blows, the short is in the wiring
Instruction Manual for terminal identification), it is

leading to the first connector or switch. important to check terminal contact between a
Use a test light or DMM as described on connector and component, or between in-line
previous page.
connectors, before replacing a suspect component.
If fuse does not blow, refer to next step.

Frequently, a diagnostic chart leads to a step that
Close each connector or switch until the fuse blows reads: Check for poor connection. Mating terminals
in order to find which circuit has the short. Connect must be inspected to assure good terminal contact.
test light or DMM at the connector to the suspect A poor connection between the male and female
circuit (disconnected) rather than at the fuse terminal at a connector may be the result of
terminals. contamination or deformation.
1998 -
MD-lsuzu
Contamination is caused by the connector halves When diagnosing circuits that have voltage applied,
being improperly connected, a missing or damaged use the voltage setting to monitor a connector (or
connector seal, or damage to the connector itself, length of a circuit) which is suspected of having an
exposing the terminals to moisture and dirt. intermittent connection but is currently operating
Contamination, usually in underhood or underbody normally.
connectors, leads to terminal corrosion, causing an 1. Connect the J 39200 Digital Multimeter to both
open circuit or intermittently open circuit. sides of a suspect connector (still connected) or
Deformation is caused by probing the mating side of from one end of a suspect circuit to the other.
a connector terminal without the proper adapter, This will continuously monitor the terminal
improperly joining the connector halves or repeatedly contacts or length of wire being checked. Refer
separating and joining the connector halves. to Meter Connections for examples of the
Deformation, usually to the female terminal contact various methods for connecting the DMM to the
tang, can result in poor terminal contact, causing an circuit.
open or intermittently open circuit.
2. Set the DMM for voltage. Since the MIN MAX
Follow the procedure below to check terminal mode does not use auto ranging, manually
contact. select the voltage range necessary before
1. Separate the connector halves. Refer to the proceeding.
J 38125-A Terminal Repair Kit or the J 38125-4
3. Press the MIN MAX button. The DMM should
instruction manual. read 100 ms RECORD (100 millisecond record)
and emit a 1/4 second beep. The DMM is now
2. Inspect the connector halves for contamination.
Contamination will result in a white or green ready to record and will generate an audible
build- up within the connector body or between tone for any change in voltage. At this point,
terminals, causing high terminal resistance, you may wish to press the PEAK MIN MAX
intermittent contact, or an open circuit. An button, which will record any voltage variations
underhood or underbody connector that shows that occur for at least 1 millisecond.
signs of contamination should be replaced in its 4. Try to simulate the condition that is potentially
entirety: terminals, seals, and connector body. causing an intermittent connection, either by
wiggling connections or wiring, test driving or
3. Using an equivalent male terminal from the
J 38125-A Terminal Repair Kit, check the performing other operations. If an open or
retention force of the female terminal in resistance is created, a voltage will be present
question by inserting and removing the male and the DMM will emit a tone for as long as
terminal to the female terminal in the connector the open or resistance exists. Any change in
body. Good terminal contact will require a voltage will cause the DMM to emit a tone for
certain amount of force to separate the no less than 1/4 second. (Listening for a tone
terminals. while manipulating wiring is very helpful for
narrowing down an intermittent connection.)
4. Using an equivalent female terminal from the
J 38125-A Terminal Repair Kit, compare the Use the MIN and MAX values when the DMM is
retention force of this terminal to the female out of sight or sound range, in noisy areas or for
test driving when it may not be possible to monitor
terminal in question by joining and separating
the male terminal to the good female terminal, the DMM.
and then joining and separating the male To check the MIN and MAX recorded voltages press
terminal to the female terminal in question. If MIN MAX once for MAX and twice for MIN. A
the retention force is significantly different variation between MIN and MAX recorded voltages
between the two female terminals, replace the (unless nearly 0 volts) suggests an intermittent open
female terminal in question (refer to the or that resistance exists and should be repaired as
J 38125- A Terminal Repair Kit). necessary.
If a visual (physical) check does not reveal the
Important: The 100 ms RECORD (100 millisecond
cause of the problem, the vehicle may be able to be record) mode is NOT the amount of time allowed to
driven with a DMM connected to the suspected perform a specific procedure. It is the amount of time
circuit. An abnormal voltage reading when the used to record each snapshot of information used for
problem occurs indicates the problem may be in that calculating AVG when in the MIN MAX mode.
circuit.
Digital Multimeter (DMM) Connections
Detecting Electrical Intermittents The previous diagnostic procedure was written to
Use the following procedure to detect intermittent detect intermittents using the DMM set to voltage.
terminal contact or a broken wire with an intermittent Whether using the current, voltage, or resistance
connection inside the insulation. setting to detect intermittents, it is necessary to
The J 39200 Digital Multimeter (DMM) has the ability connect the DMM to the circuit.
to monitor current, resistance, or voltage while
recording the minimum (MIN) and maximum (MAX)
values measured. The DMM can also be set to
display the average (AVG) value measured.
199B -
MD-lsuzu
Following are examples of the various methods of Verify Customer Concern, Check the Problem, #1
connecting the DMM to the circuit to be checked: Verify the correct normal operating behavior of the
Backprobe both ends of the connector and system also verify that the customer complaint is a
either hold the leads in place while valid failure of the system. Use any of the following
manipulating the connector or tape the leads to resources to validate the complaint.
the harness for continuous monitoring while Vehicle road test.
performing other operations or test driving.
Review the system operation in the owners
(Do not backprobe Weather Pack type
manual.
connectors.)
Check an identical vehicle.

Disconnect the harness at both ends of the
Review the circuit descriptions in the service
suspect circuit where it connects either to a
manual.
component or to other harnesses.
These questions should be asked: When and where
Use the J 35616-A Connector Test Adapter Kit
does problem occur? Do all related systems operate
to connect the DMM to the circuit.
properly? How does the problem occur? How often
If the system being diagnosed has a specified

does the problem occur? How long has the condition
pinout or breakout box, it may be used to existed / did it ever work?
simplify connecting the DMM to the circuit or for
checking multiple circuits quickly.
Preliminary Checks, #2
The goal of this step is to establish if the complaint
is visually obvious and accumulate enough data to
Additional Information
properly search for a bulletin. The initial checks may
Notice: Do not touch the electrical connections and vary due to the complexity of the system and may
pins. Do not allow the pins or connections to contact include:
brake fluid. This will damage the EBCM.
Identify parts of the system that work properly,
Continuity tests that work well for detecting review the system's schematic.
intermittent shorts to ground can be performed by Checking for open fuses, visual inspection for
setting the DMM to ohms, then pressing the PEAK
unplugged connectors and checking terminals
MIN MAX button. An audible tone will be heard for damage and tightness.
whenever the DMM detects continuity for at least
1 millisecond.
Investigating the vehicle's service history.
The J 39200 Instruction Manual is a good source of

When performing the preliminary checks observe the
unusual such as noise, vibration/feel, smell.
information and should be read thoroughly upon
receipt of the DMM as well as kept on hand for This step will save time and labor. REMEMBER, it is
reference during new procedures. essential to understand how a circuit should work
before trying to figure out why it doesn't. After
Notice: Turn off power to the test circuit before understanding how a circuit should operate, read the
attempting in-circuit resistance measurements to
schematic again, this time keeping in mind what has
prevent false readings or damage to the DMM. Do been learned by operating the circuit.
not use the DMM to measure resistance through a
solid state module. Perform Published Diagnostic System Checks, #3
System checks exist for all electrical systems and
Strategy Based Diagnostic Flow consist of two types.
Diagnostic System Check, this table is used for
Important: An understanding of the following ideas
checking various vehicle control modules for
and theories is required before performing any
diagnostic procedures. any DTC's stored by the vehicle's control
modules.
Basic theory of electricity, understand the
meaning of voltage (volts), current (amps) and

System Check, this table is used to operate the
system and determine if a abnormal condition is
resistance (ohms).
present.
Understand the affects an open or a shorted
Performing a system check will provide a systematic
wire can have on a circuit.
approach to narrowing down the possible cause of a
Able to read and understand a wiring system fault.
schematic.
Check for Bulletins, #4
Troubleshooting Procedure Checking the Technical Service Bulletins and utilizing
the Techline equipment for any bulletin information.
Use the following seven step procedure when
diagnosing an electrical system concern. Refer to Stored DTC(s), #5.1
Strategy Based Diagnostic Flow in General After performing the diagnostic system check follow
Information for a visual diagram of the following the DTC diagnostic tables in the service manual.
procedure. Symptoms, No DTCs, #5.2
After performing the system check follow the
symptom diagnostic tables in the service manual.
1998 -
MD-lsuzu
No Published Diagnostics, #5.3 Review the Headlamps Electrical Schematic

Analyze the complaint and utilize the wiring (Preliminary Checks)
schematics and circuit description to develop a plan
Review the schematic, it is essential to understand
for the diagnosing the complaint.
how a circuit should work before trying to figure out
Intermittent, #5.4 why it doesn't. After understanding how a circuit
Utilize the electrical intermittent information in the should operate, read the schematic again, this time
service manual. keeping in mind what has been learned by operating
Operating as Designed, #5.5 the circuit. Since both the low beam headlamps
If the complaint can not be verified, ensure that the operate, ensure that the following components are
vehicle is tested and is operating as designed. To operating properly.
ensure that customer satisfaction is maintained, The headlamp Switch.
verify the complaint under the conditions described
The YEL wire.
by the customer before releasing the vehicle.

Low contacts of the Headlamp Dimmer Switch.
Isolate the Root Cause, #6
A properly performed diagnostic check should isolate C100 terminal 1E.
the root cause of the complaint. The TAN wires.
Repair and Verify Completeness of Repair, #7
Grounds G105 and G109.
Once proper diagnosis has been performed and Refer to Strategy Based Diagnostic Flow.
documented, a thorough repair procedure is
performed to fix the complaint. To confirm that the Perform the System Check
repair has addressed the complaint, perform the The system check indicates that the low beam
appropriate system check. If the complaint is still headlamps operate when the high beam switch is in
present, re-examine the complaint, review the first high. Also, the high beam indicator illuminates but
four steps of your strategy based diagnostics neither high beam headlamp operates. Refer to
carefully. Strategy Based Diagnostic Flow.
Important: Also verify the complaint under the Check for Bulletins
conditions described by the customer before
Utilizing a combination of Techline tools and the
releasing the vehicle. The verification of the repair in
the form of a working test is the only way the repair information accumulated from the Preliminary
process can be considered complete, this test should Checks, check for bulletins.
either be a road test or performance test in the
Isolate the Root Cause
service bay.
At this point analyze and (diagnose the problem),
Symptom Diagnostic Example and develop text. Since the high beam indicator
illuminated when the headlamp dimmer switch was in
The following is an example of a symptom and the
correct course of action taken by the technician.
the high position, the high contacts of the headlamp
dimmer switch and the LT GRN wire between the
Important: It can not be stressed enough that headlamp dimmer switch and C100 are good.
proper preparation of: checking for possible bulletins, At this point, it is extremely unlikely that the high
DTC's, checking vehicles service history and a
beam filaments in the RH headlamp are both open
thorough screening with the customer of the problem
is detrimental to a complete repair of the vehicle and
or that both headlamp connections are bad. The
cause must be a bad connection at C100 or an
therefore the customers complete satisfaction.
open in the LT GRN wire between C100 and the
Verify the customer concern. Check RH headlamp.
the problem Repair and Verify Fix
Customer complaint is the headlamps are From isolating the root cause, basically the problem
inoperative. Verifying the normal operating procedure has been diagnosed. Using the Component Location
of the circuit and the components that share that
Table and the corresponding figure, quickly find C100
circuit. Refer to Strategy Based Diagnostic Flow. and the LT GRN wire, locate the exact trouble point
and make the repair.
Check the thoroughness of the repair by performing
a final system check on the headlamp circuit. This of
course means making sure that both high beams,

both low beams, and the high beam indicator are
working.
1993 -
MD-lsuzu
"; Headlamp
'
Switch
Heacjlamp
Lo/ Dimrner
,Hi
8wit<ch
C)' B' ^
1TA N 12
1LTGRN 11
1E\'. ^----2EJ^100 .81LTQRN 11
1 LT GRN 11 D- "'
P100
Instrument
Cluster
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1TAN 1
ILTGRN1^
11 c>\ High Beam
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A
Jl 12 I .
\ ^0
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t
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.8BLK 150
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2BLK150 0.5BLK151 Cell 14
3BLK 150
AG109 AG105 LG200
61699
Checking Aftermarket Accessories Troubleshooting with a Test Light

A test light can simply and quickly check a circuit for
Important: Do not connect aftermarket accessories
into the following circuits: voltage. The following two types of test lights the
J 34142-B test light and J 21008-A self-powered test
SIR circuits, all such circuits are indicated on
light can be used in diagnosing vehicle symptoms.
circuit diagrams with the SIR symbol. Refer to
SIR Service Precautions Caution in Cautions Review the following text before using either tool.
J 34142-B test light is comprised of a 12 volt light
and Notices.
bulb with an attached pair of leads. To properly
OBDII circuits, all such circuits are indicated on
operate this tool use the following procedure.
circuit diagrams with the OBDII symbol.
1. Attach one lead to ground.
Refer to OBD II Symbol Description Notice in
Cautions and Notices. 2. Touch the other lead to various points along the
circuit where voltage should be present.
Always check for aftermarket accessories (non-OEM)
3. When the bulb illuminates, there is voltage at
as the first step in diagnosing electrical problems. If the point being tested.
the vehicle is so equipped, disconnect the system to
verify that these add-on accessories are not the Notice: Do not use a self-powered test light in
cause of the problems. circuits that contain solid state components, as
Possible causes of vehicle problems related to

damage to these components may result.
aftermarket accessories include: J 21008-A self-powered test light is comprised of a
light bulb, battery, and two leads. If the leads are

Power feeds connected to points other than the
battery. touched together the bulb illuminates. A self-powered
test light is used only on an unpowered circuit and

Antenna location. can check for continuity of a circuit. To properly

Transceiver wiring located too close to vehicle operate this tool use the following procedure.
electronic modules or wiring. 1. Remove the fuse which feeds the circuit.

Poor shielding or poor connectors on antenna 2. Select two specific points along the circuit
feed line. through which there should be continuity.
Check for recent service bulletins detailing 3. Connect one lead of the self-powered test light
installation guidelines for aftermarket to each point. If there is continuity the test light
accessories. circuit will be completed and the bulb
illuminates.
1998 -
MD-lsuzu
Troubleshooting with a Digital Multimeter Diodes and solid state components in a circuit can
cause a DMM to display a false reading. To find out
Digital Multimeter (DMM) if a component is affecting a measurement take a
reading once, then reverse the leads and take a
Notice: Do not insert a DMM test probe into any
connector or fuse block terminal. The diameter of the second reading. If the readings differ the solid state
DMM test probe will deform most terminals. A component is affecting the measurement. Following
deformed terminal can cause a poor connection are examples of the various methods of connecting
the DMM to the circuit to be checked:
between the device, which can result in system
failures. Always use the Connect Test Adapter Kit
Backprobe both ends of the connector and
when using a DMM in order to probe terminals. either hold the leads in place while
manipulating the connector or tape the leads to
Important: Circuits which include any solid state the harness for continuous monitoring while you
control modules, such as the PCM, should be tested
perform other operations or test driving.
only with a 10 megohm or higher impedance
J 39200 digital multimeter.
Disconnect the harness at both ends of the
suspected circuit where it connects either to a
The J 39200 Instruction Manual is a good source of component or to other harnesses.
information and should be read thoroughly upon
receipt of the DMM as well as kept on hand for Use the J 35676 Connector Test Adapter Kit in
order to connect the DMM to the circuit.
reference during new procedures.
If the system that is being diagnosed has a
A DMM should be used instead of a test light to
specified pinout or breakout box, it may be
check for voltage. While a test light shows whether
used in order to simplify connecting the DMM
voltage is present, a DMM indicates how much
to the circuit or for checking multiple circuits
voltage is present.
quickly.
When testing for voltage or continuity at the
connection, it is not necessary to separate the two Troubleshooting with a Short Finder
halves of the connector. Unless testing a Weather The J 8681 -A short finder can locate hidden shorts
Pack or a Metri Pack connector 150 series and to ground. The short finder creates a pulsing
below, always probe the connector from the back. magnetic field in the shorted circuit and shows the
Always check both sides of the connector. An location of the short through the body trim or
accumulation of dirt and corrosion between contact sheet metal.
surfaces is sometimes a cause of electrical
problems. Using Connector Test Adapters
A DMM should be used instead of a self-powered
Notice: Do not use paper clips or other substitutes
test light to check for circuit continuity. The
as they can damage terminals and cause incorrect
ohmmeter function on a DMM shows how much measurements.
resistance exists between two points along a circuit.
Low resistance in a circuit means good continuity. The J 35616 Connect Test Adapter Kit contains
various terminal pigtails for probing terminals.
Important: Disconnect the battery when measuring
resistance with a DMM. This prevents incorrect
Connector test adapter kit allows the DMM to
conduct tests and measurements at separated
readings.
connectors, fuse, or relay terminals.
DMMs apply such a small voltage to measure
resistance that the presence of voltages can upset a Using Fused Jumper Wires
resistance reading.
Important: A fused jumper may not protect solid
state components from being damaged.
The J 36169 fused jumper includes small clamp
connectors that provide adaptation to most
connectors without damage. This fused jumper wire
is supplied with a 20 A fuse which may not be
suitable for some circuits. Do not use a fuse with a
higher rating than the fuse that protects the circuit
being tested.
1998 -
MD-lsuzu
Testing for Voltage 1. Remove the negative battery cable.
Notice: Do not insert a DMM test probe into any 2. Place the leads of the DMM in COM (black)
and V/ohms (red) inputs.
connector or fuse block terminal. The diameter of the
DMM test probe will deform most terminals. A 3. Set the rotary dial of the DMM to ohms.
deformed terminal can cause a poor connection 4. Press the PEAK MIN MAX button.
5. Connect one lead of the DMM to one end of
the circuit to test.
when using a DMM in order to probe terminals.
6. Connect the other lead to the other end of the
This test checks for voltage along a wire through a
circuit.
connection or switch.
7. If the DMM displays low or no resistance and a
tone is heard the circuit being tested has good
continuity.
|n'otZtAIITimes|
i
On F use
B ock
/
/ /'"^
Off
\
A
EC)
&Switch
'i- '- /.
P\ Test Light \
(/(Or DMM) \
r \
\
^ ..! 3L-U
Solenoid
61704
1. Apply power to the circuit.

2. Place meter leads in the COM (black) and 61700
Vohm inputs.
With a Test Light
3. Place the rotary switch (meter) in the V (AC) or
V (DC) position. This test checks for continuity along a wire, through
a connection or switch.
4. Connect the positive lead of a DMM to the end
of the wire, (or to one side of the connection or Notice: Do not insert a DMM test probe into any
switch) which is closer to the battery. connector or fuse block terminal. The diameter of the
DMM test probe will deform most terminals. A
5. Connect the negative lead to the other end of deformed terminal can cause a poor connection
the wire (or the other side of the connection or
switch). between the device, which can result in system
6. Operate the circuit. when using a DMM in order to probe terminals.
Testing for Continuity 1. Remove the fuse from the suspect circuit.
With a DMM 2. Connect one lead of the test light to one end of
the circuit to test.
Continuity tests work well for detecting intermittent
shorts to ground and can be performed by setting 3. Connect one end of the circuit to be tested to
ground.
the DMM to ohms, then pressing the PEAK MIN
MAX button. An audible tone is heard whenever the 4. If the test light is not self-powered connect the
DMM detects continuity for at least 1 millisecond. other lead to a battery positive voltage source.
This test checks for continuity along a wire, through 5. If the test light illuminates (full intensity) then
a connection or switch. the circuit being tested has good continuity.
Notice: Do not insert a DMM test probe into any

connector or fuse block terminal. The diameter of the
DMM test probe will deform most terminals. A
deformed terminal can cause a poor connection
when using a DMM in order to probe terminals.
1998 -
MD-lsuzu
Testing for Short to Ground

Battery Disconnected
Notice: Do not use self-powered test light in
a
mFuse
circuits that contain solid state components, as
damage to these components may result.
This test checks a short to ground along a wire or
through a connection, or switch.
61706
With a Test Light

1. Remove the open fuse.
2. Disconnect the load.
3. Connect a test light across the fuse terminals
(be sure that the fuse is powered).
61705
4. Beginning near the fuse block, wiggle the
With a DMM Set to Ohmmeter Function harness from side to side. Continue this at
1. Remove the open fuse. watching the test light.
2. Disconnect the battery. 5. When the test light glows there is a short to
3. Disconnect the load. ground in the wiring near that point.
4. Connect one lead of the DMM to the fuse With a Self-Powered Test Light
terminal on the load side.
1. Remove the open fuse and disconnect the
5. Connect the other lead to a known good battery and load.
ground.
2. Disconnect the battery.
harness from side to side. Continue this at 3. Disconnect the load.
convenient points (about 6 inches apart) while 4. Connect one lead of a self-powered test light to
watching the DMM. the fuse terminal on the load side.
7. When the DMM displays low or no resistance, 5. Connect the other lead to a known good
there is a short to ground in the wiring near ground.
that point.
harness from side to side. Continue this at
With a DMM Set to Voltage Function
1. Remove the open fuse. watching the self-powered test light.
2. Disconnect the load. 7. When the self-powered test light glows, there is
a short to ground in the wiring near that point.
3. Connect a DMM across the fuse terminals (be
sure that the fuse is powered).
harness from side to side. Continue this at
watching the DMM.
5. When the DMM displays voltage, there is a

short to ground in the wiring near that point.
1998 -
MD-lsuzu
8-166Wiring Systems Body and Accessories
Fuse Powering Several Loads 7. Press the MIN MAX button twice for the MIN
1. Review the system schematic and locate the value and note the value.
fuse that is open. 8. Determine the difference between the MIN and
MAX values.
2. Open the first connector or switch leading from
the fuse to each load. If the variation between the recorded MIN
a DMM across the fuse terminals and MAX voltage values is one volt or
3. Connect
(be sure that the fuse is powered). greater an intermittent open or high
resistance condition exists. Repair condition

When the DMM displays voltage the short is as necessary.
in the wiring leading to the first connector or
If the variation between the recorded MIN
switch.
and MAX voltage values is less than one volt
If the DMM does not display voltage refer to
an intermittent open or high resistance

the next step.

condition does not exist.
4. Close each connector or switch until the DMM
displays voltage in order to find which circuit Testing for Poor Connections
has the short. Most intermittents are caused by faulty electrical
connections or wiring. Occasionally a sticking relay
Testing for Electrical Intermittents
or solenoid can also cause an intermittent failure.
Use the following procedure to detect an intermittent Some items to check are:
circuit that is currently operating normally.
Poor mating of connector halves or terminals
Important: The J 39200 Digital Multimeter (DMM) not fully seated in the connector body
must be used to perform the following procedure (backed out).
since the DMM can monitor current, resistance or . Dirt or corrosion on the terminals.
voltage while recording the minimum (MIN), and

The terminals must be clean and free of any
maximum (MAX) values measured.
foreign material which could impede proper
1. Connect the J 39200 Digital Multimeter (DMM) terminal contact.
to both sides of a suspected connector, (still
Damaged connector body.
connected) or from one end of a suspected
circuit to the other.

Exposure of terminals to moisture and dirt
causing improper terminal orientation with the
Important: Refer to Troubleshooting with a Digital component or mating connector.
Multimeter
Improperly formed or damaged terminals.
2. Select the appropriate voltage mode on
Check all connector terminals in problem
the DMM.
circuits in order to ensure good contact tension.
3. Press the Range button to select the desired Use a corresponding mating terminal to check
voltage range. for proper tension. Refer to Connector Repairs
for the specific procedure.
4. Press the MIN MAX button. The DMM
displays 100 ms RECORD and emits an
Poor terminal to wire connection. Some
audible tone (beep). conditions which fall under this description
Important: The DMM is now ready to record and are poor crimps, poor solder joints, crimping
generates an audible tone for any change in voltage. over wire insulation rather than the wire itself
and corrosion in the wire to terminal contact
The 100 ms RECORD mode is the amount of time
area, etc.
used to record each snapshot of information used for
calculating the AVG voltage.

Wire insulation which is rubbed through. This
causes an intermittent short as the bare area
5. Simulate the condition that is potentially causing touches other wiring or parts of the vehicle.
an intermittent connection, either by wiggling
Wiring broken inside the insulation. This
the connections or the wiring, also by test
driving or performing other operations. If an condition could cause a continuity check to
show a good circuit but if only one or two
open or a high resistance condition is created
voltage is present and the DMM emits a tone strands of a multi-strand type wire are intact,
for as long as the condition exists. resistance could be far too high.
In order to avoid any of the above problems when
6. Press the MIN MAX button once to display the making wiring or terminal repairs always follow the
MAX value and note the value.
instructions for wiring and terminal repair detailed in
Wiring Repairs and Connector Repairs.
1998 -
MD-lsuzu
Checking Terminal Contact Wiring Repairs

When diagnosing an electrical system that utilizes
Circuit Protection
Metri-Pack 150/280/480/630 series terminals (refer to
the J 38125-A Terminal Repair Kit or the J 38125-4 Important: After you make any electrical repair,
Instruction Manual for terminal identification), it is always test the circuit by operating the devices in
important to check terminal contact between a the circuit. This confirms not only that the repair is
connector and component, or between in-line correct, but also that the cause of the complaint was
connectors, before replacing a suspected component. correctly identified.
Frequently, a diagnostic leads to a step that reads: All electrical circuits are protected against excessive
Check for poor connection. Mating terminals must be loads which might occur because of shorts or
inspected to assure good terminal contact. A poor overloads in the wiring system. A fuse or circuit
connection between the male and female terminal at breaker provides such protection. A short may cause
a connector may be the result of contamination or a fuse to blow or a circuit breaker to open.
deformation.
Contamination is caused by the connector halves Fuses
being improperly connected. A missing or damaged
connector seal, damage to the connector itself or
exposing the terminals to moisture and dirt, can
cause contamination. Contamination, usually in the
underhood or underbody connectors, leads to
terminal corrosion, causing an open circuit or
intermittently open circuit.
Deformation is caused by probing the mating side of
N|D |
a connector terminal without the proper adapter,
improperly joining the connector halves or repeatedly
separating and joining the connector halves.
a^D
Deformation, usually to the female terminal contact
tang, can result in poor terminal contact causing an
open or intermittently open circuit.
Follow the procedure below to check terminal
contact.
1. Separate the connector halves. Refer to the
J 38125-A Terminal Repair Kit or the J 38125-4
instruction manual.
2. Inspect the connector halves for contamination. 8786
Contamination will result in a white or green The fuse is the most common method of automotive
build-up within the connector body or between wiring circuit protection. Whenever there is an
terminals. This causes high terminal resistance, excessive amount of current flowing through a circuit
intermittent contact, or an open circuit. An the fusible element will melt and create an open or
underhood or underbody connector that shows incomplete circuit. Fuses are a "one time" protection
signs of contamination should be replaced in its device and must be replaced each time the circuit is
entirety: terminals, seals, and connector body. overloaded. To determine if a fuse is blown, remove
3. Using an equivalent male terminal from the the suspect fuse and examine the element in the
J 38125-A Terminal Repair Kit, check that the fuse for a break. If the element is broken, replace
retention force is significantly different between the fuse with one of equal current rating.
the two female terminals. Replace the female
terminal in question (refer to the J 38125-A
Terminal Repair Kit.)
If a visual physical check does not reveal the cause
of the problem, connect a DMM to the suspected
circuit. An abnormal voltage reading when the
problem occurs indicates the problem may be in that
circuit.
1998 -
MD-lsuzu
Fuse Types Short Circuits Caused by Damaged

Wire Insulation
Current Rating Amperes Color
If the damage is minor, locate the problem and tape
Auto Fuses, Mini Fuses
over the wire. If the damage is more extensive,
2 Gray replace the faulty segment of the wire. Follow the
3 Violet instructions below in order to repair copper and
shielded cables.
5 Tan
7.5 Brown Wire Size Conversion Table

10 Red Metric Wire Sizes (mm[2]) AWG Sizes
15 Blue 24
0.22
20 Yellow 22
0.35
25 White 20
0.5
30 Green 18
0.8
Maxi Fuses 1.0 16
20 Yellow 14
2.0
30 Light Green 12
3.0
40 Orange 10
5.0
60 Blue 8
8.0
13.0 6
Circuit Breakers
19.0 4
A circuit breaker is a protective device that is
designed to open the circuit when a current load is 32.0 2
in excess of the rated breaker capacity. If there is a 1/0
50.0
short or other type of overload condition in the
circuit, the excessive current will open the circuit
Splicing Copper Wire Using Splice Clips
between the circuit breaker terminals. Two types of
circuit breakers are used. The first is a circuit Tools Required
J 38125 Terminal Repair Kit
breaker. This type will open when excessive current
passes through it for a period of time. It will close 1. Open the harness.
again after a few seconds. If the cause of the high If the harness is taped, remove the tape.
current is still present, it will open again. It will
To avoid wiring insulation damage, use a
continue to cycle open and closed until the condition
sewing ripper in order to cut open the
causing the high current is removed. The second
type of circuit breaker is a positive temperature harness.
coefficient (PTC) circuit breaker. This type greatly If the harness has a black plastic conduit,
increases its resistance when excessive current pull out the desired wire.
passes through it. The excessive current heats the 2. Cut the wire.
PTC device. As the device heats, its resistance . Cut as little wire off the harness as possible.
increases. Eventually the resistance gets so high that
the circuit is effectively open. Unlike the ordinary

Ensure that each splice is at least 40 mm
circuit breaker, the PTC unit will not reset until the (1.5 in) away from other splices, harness
circuit is opened, removing the voltage from its branches, and connectors. This will help
prevent moisture from bridging adjacent
terminals. Once the voltage is removed, the circuit
splices and causing damage.
breaker will re-close within a second or two.
Typical Electrical Repairs

An open circuit is an incomplete circuit. Power
cannot reach the load or the ground. If a circuit is
open, active components do not energize. A short
circuit is an unwanted connection between one part
of the circuit and either the ground or another part of
the circuit. A short circuit causes a fuse to blow or a
circuit breaker to open.
1998 -
MD-lsuzu
3. Strip the insulation.

Use wire of equal or greater size than the

original. The wire's insulation must have the

same or higher temperature rating.

You may use general purpose insulation for
areas that are not subject to high
temperatures.

Use a cross-linked polyethylene insulated
wire for areas where high temperatures are
expected.
-
Cross-linked polyethylene wire may be
used to replace PVC, but you may not
replace cross-linked polyethylene
with PVC.
-
Cross-linked polyethylene wire is not fuel
resistant and should not be used to
replace wire where there is the possibility
of fuel contact.
8788

Select the correct size opening in the wire
stripper or work down from the largest size. 5. Apply steady pressure until the crimp
tool closes.

Ensure that the wires extend beyond the clip
in each direction.

Ensure that no strands of wire are cut loose.

Ensure that no insulation is caught under
the clip.
8787
4. Crimp the wires.

Select the proper clip to secure the splice.
Follow the instructions in the J 38125 Kit in
order to determine the proper clip size crimp
tool and anvil. 8790

Overlap the two stripped wire ends and hold 6. Crimp the splice on each end.
them between your thumb and forefinger.
Center the splice clip under the stripped
wires and hold it in place.
1998 -
MD-ISUZU
8791 8795
7. Apply 60/40 rosin core solder to the opening in 9. You may tape the wire again if the wire does
the back of the clip. Follow the manufacturer's not belong in a conduit or another harness
instructions for the solder equipment. covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Crimp and

Seal Splice Sleeves
Crimp and seal splice sleeves may be used on all
types of insulation except tefzel and coaxial to form
a one-to-one splice. They are to be used where
there are special requirements such as moisture

sealing. Follow the instructions below in order to
splice copper wire using crimp and seal splice
sleeves.
Crimp And Seal Splice Chart

Color Splice Crimp Tool Nest Wire Gage AWG/
Sleeve Color (Metric)
Salmon Red 20, 18,/ (0.5, 0.8)
Blue Blue 16, 14/(1.0, 2.0)
Yellow Yellow 12, 10/(3.0, 5.0)
8792
8. Tape the splice. Roll on enough tape in order

to duplicate the thickness of the insulation on 1. Open the harness.
If the harness is taped, remove the tape.
the existing wires.
To avoid wiring insulation damage, use a

harness.
If the harness has a black plastic conduit,
pull out the desired wire.
1998 -
MD-lsuzu
2. Cut the wire.

Cut as little wire off the harness as possible.

Ensure that each splice is at least 40 mm
(1.5 in) away from other splices, harness
branches, and connectors. This will help
prevent moisture from bridging adjacent
splices and causing damage.
3. Strip the insulation.

Find the correct wire size.

Select the correct size opening in the wire

stripper or work down from the largest size.
Strip approximately 7.5 mm (5/16 in) of
8797
insulation from each wire to be spliced.
6. Shrink the insulation around the splice.
4. Select the proper splice sleeve according to the
Use a torch in order to apply heat where the

wire size.
barrel is crimped.
Gradually move the heat barrel to the open
end of the tubing, shrinking the tubing as the
heat is moved along the insulation. A small
amount of sealant will come out of the end
of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted/Shielded Cable

Twisted/shielded cable is used in order to protect
wiring from electrical noise. Two-conductor cable of
this construction is used between the radio and the
Delco-Bose speaker/amplifier units and other
applications where low level, sensitive signals must
be carried. Follow the instructions below in order to
repair the twisted/shielded cable.
8796
5. Insert the wires into the splice sleeve

and crimp.

Place the splice tool in the nest so that the
crimp falls at point 1 on the splice. The
sleeve has a stop in the middle of the barrel
in order to prevent the wire from going
farther.
Close the hand crimper handles slightly in
order to hold the splice sleeve firmly in the
proper nest.
Insert the wire into the splice until it hits the
barrel stop.
Close the handles of the J 38125 until the
crimper handles open when released. The
8798
crimper handles will not reopen until the
proper amount of pressure is applied to the 1. Remove the outer jacket. Use care not to cut
splice sleeve. into the drain wire of the mylar tape.
2. Unwrap the tape. Do not remove the tape. The

tape will be used in order to rewrap the twisted
conductors after you have made the splice.
1998 -
MD-lsuzu
8799 8801
3. Prepare the splice. Untwist the connectors and 5. Tape over the entire cable. Use a winding
follow the splicing instructions for copper wire. motion when you apply the tape.
Splicing Inline Harness Diodes

Many vehicle electrical systems use a diode to
isolate circuits and protect the components from
voltage spikes. When installing a new diode use the
following procedure.
1. Open the harness.

If the harness is taped, remove the tape.
MQ 3 To avoid wiring insulation damage, use a

harness.
If the harness has a black plastic conduit,
pull out the diode.
2. If the diode is taped to the harness, remove all

of the tape.
3. Check and record the current flow direction and

orientation of diode.
4. Remove the inoperative diode from the harness

8800 with a suitable soldering tool.
4. Re-assemble the cable.
Important: If the diode is located next to a

Rewrap the conductors with the mylar tape.
connector terminal remove the terminal(s) from the

Use caution not to wrap the drain wire in connector to prevent damage from the soldering tool.
the tape.
5. Carefully strip away a section of insulation next
Follow the splicing instructions for copper to the old soldered portion of the wire(s). Do
wire and splice the drain wire. not remove any more than is needed to attach

Wrap the drain wire around the conductors the new diode.
and tape with mylar tape.
6. Check current flow direction of the new diode,
being sure to install the diode with correct bias.
Reference the appropriate service manual
wiring schematic to obtain the correct diode
installation position.
7. Attach the new diode to the wire(s) using

60/40 rosin core solder. Before soldering attach
some heat sinks (aluminum alligator clips)
across the diode wire ends to protect the diode
from excessive heat. Follow the manufacturer's
instruction for the soldering equipment.
1998 -
MD-lsuzu
8. Reinstall terminal(s) into the connector body if Connector Repairs

previously removed.
9. Tape the diode to the harness or connector

Push-to-Seat Connector
using electrical tape. Follow the steps below in order to repair
push-to-seat connectors.
Important: To prevent shorts to ground and water
intrusion, completely cover all exposed wire and 1. Remove the terminal position assurance (TPA)
diode attachment points with tape. device, the connector position assurance (CPA)
device, and/or the secondary lock.
H02S Wiring Repairs
Notice: Do not solder repairs under any
circumstances as this could result in the air
reference being obstructed.
If the heated oxygen sensor pigtail wiring, connector,
or terminal is damaged the entire oxygen sensor
assembly must be replaced. Do not attempt to repair
the wiring, connector, or terminals. In order for the
sensor to function properly it must have a clean air
reference. This clean air reference is obtained by
way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or
terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when
servicing the heated oxygen sensor:

Do not apply contact cleaner or other materials
to the sensor or vehicle harness connectors.
8802
These materials may get into the sensor,
causing poor performance. Also, the sensor 2. Separate the connector halves.
pigtail and harness wires must not be damaged
in such a way that the wires inside are
exposed. This could provide a path for foreign
materials to enter the sensor and cause
performance problems.
Neither the sensor nor vehicle lead wires
should be bent sharply or kinked. Sharp bends,
kinks, etc., could block the reference air path
through the lead wire.
Do not remove or defeat the oxygen sensor
ground wire (where applicable). Vehicles that
utilize the ground wire sensor may rely on this
ground as the only ground contact to the
sensor. Removal of the ground wire will also
cause poor engine performance.
To prevent damage due to water intrusion, be

2
sure that the peripheral seal remains intact on
the vehicle harness connector.
The engine harness may be repaired using the 8803
J 38125-A Crimp and Splice Seals Terminal
3. Use the proper pick or removal tool (1) in order
Repair Kit. to release the terminal.
4. Gently pull the cable and the terminal (2) out of

the back of the connector.
1998 -
MD-lsuzu
8804 8805
5. Re-form the locking device if the you are going 2. Use the proper pick or removal tool in order to
to reuse the connector. remove the terminal.
6. Make the repair. Gently pull the lead.

Slip the cable seal away from the terminal.

Insert the pick from the front of the

Cut the wire as close to the terminal as connector into the canal.
possible. Pry up on the tab.

Slip a new cable seal onto the wire. Push on the lead in order to remove the lead.
Strip 5 mm (3/16 in) of insulation from 3. If the terminal is to be reused, re-form the
the wire. locking tang.

Crimp new terminal to the wire.
a 4. Make the repair.
Pull the terminal wire out of the
Solder the crimp with rosin core solder.

connector body.
Slide the cable seal toward the terminal.
Cut the wire as close to the terminal as
Crimp the cable seal and the insulation.
possible.
If the connector is outside of the passenger
Strip 5 mm (3/26 in) of insulation from
compartment, apply grease to the connector. the wire.
In order to reuse a terminal or lead
Crimp the new terminal to the wire.
assembly, see the splicing copper wire.
Solder the crimp with rosin core solder.
Refer to Wiring Repairs Wiring Repairs.

Carefully pull on the wire in order to draw

Ensure that the cable seal is kept on the
the terminal into the connector body until
terminal side of the splice.
it locks.
Insert the lead from the back until it
catches. Connector Position Assurance Locks
Install the TPA, CPA and/or the The Connector Position Assurance (CPA) is a small
secondary locks. plastic insert that fits through the locking tabs of all
the SIR system electrical connectors. The CPA
Pull-to-Seat Connector ensures that the connector halves cannot vibrate
Follow the steps below in order to repair pull-to-seat apart. You must have the CPA in place in order to
type connectors. ensure good contact between the SIR mating
Separate the connector halves. terminals.
1.
Terminal Position Assurance Locks
The Terminal Position Assurance (TPA) insert
resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal
securely seated in the connector body. Do not
remove the TPA from the connector body unless you
remove a terminal for replacement.
1998 -
MD-lsuzu
Power and Grounding Schematic References

Subsection Name
Headlights: Daytime Running Lights (DRL) Cell 102 8Lighting Systems

Exterior Lamps Cell 110 8Lighting Systems
Power and Grounding Schematic Icons

AA 19384
1998 -
MD-lsuzu
Power Distribution Schematics (Cell 10: Ext Lighting, Generator/Chassis, Wiper HVAC MaxiFu
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MD-lsuzu
1998 -
MD-lsuzu
Component Locator
Power and Grounding Components

In the center of the lower IP, behind the Power and Grounding
Accessory Relay

Auxiliary Power Posts In the center of the console
Auxiliary Relay

Power and Grounding
Battery, Inboard On the outboard side of the right frame rail
Component Views
Power and Grounding
Battery, Outboard On the outboard side of the right frame rail
Component Views
From the right front of the cab to the right Power and Grounding
Cab Ground Cable
front of the frame rail Component Views

Cab Interface Connector Under the hood, in the center of the Power and Grounding
Housing bulkhead Component Views

In the center of the IP, to the right of Power and Grounding Power and Grounding
Cigar Lighter
the radio Component Views Connector End Views
Power and Grounding Power and Grounding
Cigar Lighter *C1 In the IP harness to the cigar lighter
Power and Grounding Power and Grounding
Cigar Lighter *C2 In the IP harness to the cigar lighter
Diagnostic Connector Power and Grounding

Under the left side of the IP
(1 cavity) Connector End Views

Diagnostic Connector Power and Grounding
(20 cavities) Under the left side of the IP
Connector End Views

Below the left side of the IP to the right of
the steering column, in joint connector 1,
Diode Module 1
row 1, terminals 1A, 1B, 1C, 1D, 1E, 1F,

1G, 1H, 1J and 1K
the steering column, in joint connector 2,
Diode Module 2
row 1, terminals 1A, 1B, 1C, 1D, 1E, 1F,

1G, 1H, 1J and 1K
Engine Controls Power and Grounding
Behind the left side of the front bumper
Connector Housing Component Views

In the engine harness to starter
Fusible Link
solenoid C2
Ground Block On the right frame, inboard, part of the Power and Grounding
(6 cavities) negative battery cable Component Views

the steering column, joint connector 1, row
Ground Buss 1
2, terminals 2A, 2B, 2C, 2D, 2E, 2F, 2G,

2H, 2J and 2L
Ground Buss 2

3H, 3J and 3L
Ground Buss 3

2H, 2J and 2L
1998 -
MD-lsuzu
Power and Grounding Components (cont'd)

In the upper IP harness, under the crash
Ground Buss 4 pad, in the top of the IP, row 2, terminals
2A, 2B, 2C, 2D, 2E, 2F, 2G, 2H, 2J and 2L

Under the crash pad, in the top of the IP,
Ground Buss 5 joint connector 1, row 3, terminals 3A, 3B,
3C, 3D, 3E, 3F, 3G, 3H, 3J and 3L
Ignition Relay 1
Ignition Relay 2
Ignition Relay 3
Ignition Switch Power and Grounding Power and Grounding

On the right side of the steering column
In the right top of the IP, under the Power and Grounding
IP Fuse Block
access panel Component Views

On the left rear of the cab, below the Power and Grounding
MaxiFuse Block 1
cab bridge Component Views

On the left rear of the cab, below the Power and Grounding
MaxiFuse Block 2
cab bridge Component Views

Memory Clear Connector Power and Grounding
Under the left side of the IP
(1 cavity) Connector End Views

From the outboard battery NEG terminal to
the outside right frame rail with a feed to Power and Grounding
Negative Battery Cable
the ground block on the inside of the right Component Views

frame rail
Negative Battery to From the outboard battery NEG terminal to Power and Grounding
Battery Cable the inboard battery NEG terminal Component Views

From the positive battery cable POS
Power and Grounding
Positive Battery Cable terminal to the starter solenoid, at the
Component Views
starter motor
Positive Battery Cable From the outboard battery POS terminal to Power and Grounding
(Dual Batteries) the starter solenoid Component Views

From the outboard battery POS terminal to
Positive Battery to Power and Grounding
the inboard battery POS terminal with a
Battery/Feed Cable Component Views

feed to the MaxiFuse block
In the right top of the IP, under the Power and Grounding
Relay Center 1
access panel Component Views

In the center of the lower IP, behind Power and Grounding
Relay Center 2
the panel Component Views

In the right side of the lower IP, in front of
Relay Center 3
the blower motor, behind the panel

Starter Motor On the lower right side of the engine from Power and Grounding
Ground Cable the starter to the right frame rail Component Views
Transmission Connector Behind the engine at the left top of the bell
Power and Grounding
Jumper (C412) (Manual housing, in connector C412, in the front
Transmission)
Component Views
chassis harness
The in-line connector in the front chassis
Upfitter Connector Power and Grounding
(1 cavity) harness, by the right frame rail, inboard of
Component Views
the batteries
The in-line connector in the front chassis
Upfitter Connector Power and Grounding
harness, by the right frame rail, inboard of
(4 cavities) Component Views

the batteries
1998 -
MD-lsuzu

The in-line connector in the lower IP
Upfitter Connector, Power and Grounding
harness, below the IP, to the left of the
Interior (6 cavities) Connector End Views

center of the cab
In the front turn signal harness to the dual
C101 (2 cavities) (Dual Power and Grounding
electric horn harness, behind the left side
Electric Horns) Component Views

of the front bumper impact bar
In the front turn signal harness, to the front

Power and Grounding Inline Harness Connector
C105 (5 cavities) chassis harness, on the left top of the #1
Component Views End Views
crossmember
In the front turn signal harness, to the front
C107 (4 cavities) chassis harness, on the left top of the #1
crossmember
In the timing and injection rate control
system (TICS) harness from the engine,

C111 (3 cavities) behind the lower left front of the front
bumper, in the engine controls connector
housing

housing
housing

Power and Grounding
Component Views
housing
In the engine harness, to the front chassis Power and Grounding Inline Harness Connector
C116(8 cavities)
harness, at the right front of the engine Component Views End Views
In the front chassis harness, to the engine Power and Grounding Inline Harness Connector
C118 (2 cavities)
harness, at the right front of the engine Component Views End Views
In the starter harness, to the WHT fusible Power and Grounding
C120 (1 cavity)
link, starter solenoid C2 Component Views
C121 (2 cavities)
In the starter harness, to the BLU and the Power and Grounding
BLK fusible links, starter solenoid C3 Component Views

In the lower IP harness, to the front
C200 (56 cavities) chassis harness, in the left center of the
cab, in the cab interface connector
C202 (56 cavities) Power and Grounding Inline Harness Connector
chassis harness, in the left center of the
Power and Grounding
C205 (1 cavity) chassis harness, in the left center of the
Component Views
1998 -
MD-13UZU

Power and Grounding
C207 (1 cavity) chassis harness, in the left center of the
Component Views
In the lower IP harness, to the roof Inline Harness Connector
C208 (5 cavities)
harness End Views

In the lower IP harness, to the floor Inline Harness Connector
C210 (16 cavities)
harness End Views

In the lower IP harness, to the dash Inline Harness Connector
C211 (6 cavities)
harness, under the hood, on the right side End Views

In the lower IP harness, to the upper IP
Inline Harness Connector
C212 (84 cavities) harness, in the left center of the IP at
End Views
the floor
In the auxiliary power harness, to the floor Inline Harness Connector
C213 (2 cavities)
harness End Views

In the lower IP harness, to the park brake Power and Grounding Inline Harness Connector
C214 (2 cavities)
jumper, under the right seat Component Views End Views
In the lower IP harness jumper, under the Power and Grounding Inline Harness Connector
C215 (2 cavities)
right seat Component Views End Views
C216 (6 cavities) Inline Harness Connector

In the upper IP harness
(Lighted Mirror) End Views

In the front chassis harness, to the ABS-air
C400 (15 cavities) brake harness, on the inboard side of the
(ABS-Air) left frame rail, to the left of the End Views
transmission
In the front chassis harness, to the rear
chassis and taillamps harness, on the Power and Grounding Inline Harness Connector
C402 (8 cavities)
inboard side of the right frame rail, inboard Component Views End Views
of the batteries
In the front chassis harness, to the rear
chassis and taillamps harness, on the Power and Grounding
C404 (3 cavities)
inboard side of the right frame rail, inboard Component Views

of the batteries
On the inboard side of the right frame rail, Power and Grounding
C406 (5 cavities)
inboard of the batteries Component Views

In the front chassis harness, to the starter
harness, on the bell housing mounting
(Automatic Transmission) Component Views End Views
bracket
C407 (14 cavities) In the front chassis harness, capped, on Power and Grounding Inline Harness Connector
(Manual Transmission) the bell housing mounting bracket Component Views End Views
In the front chassis harness, the sealed

C407 Connector Cover Power and Grounding
connector, on the bell housing mounting
(Automatic Transmission) Component Views

bracket
In the rear chassis and taillamps harness,
C408 (2 cavities) to the air brake moisture ejector valve, Power and Grounding
(Long Wheelbase) approximately 15 cm (5.9 in) from the Component Views

ground connectors breakout
to the fuel tank/s harness, at the right Power and Grounding
C410 (6 cavities)
frame rail forward of the back of the cab Component Views

crossmember
In the front chassis harness, to the
C412 (8 cavities) transmission harness or connector C412 Power and Grounding Inline Harness Connector
(Automatic Transmission) jumper, behind the engine, at the top of the Component Views End Views
bell housing
199B -
MO-lsuzu

In the front chassis harness, to the
transmission harness, on inboard side of
C413 (4 cavities)
the left frame rail, to the left of the

transmission
(Automatic Transmission) Component Views End Views
bracket
In the starter harness, to the front chassis
(Manual Transmission) Component Views End Views
bracket
C418 (1 cavity) Power and Grounding

bracket
(Cover-Air Brakes) Component Views

bracket
(Manual Transmission) Component Views

bracket

bracket
(Manual Transmission) Component Views

bracket
C501 (8 cavities) In the left door harness, in the left door
End Views
In the left mirror connector harness, to the Inline Harness Connector
C503 (2 cavities)
heated or lighted outside rearview mirror End Views

In the right door harness, to the right Inline Harness Connector
C601 (8 cavities)
In the right mirror connector harness, to the Inline Harness Connector

C603 (2 cavities)

On the right frame rail, forward of the Power and Grounding
C702 (3 cavities)
rear axle Component Views

In the lower IP harness, part of diode
D202 module 1, plugged into joint connector 1,
terminals G1, H1, J1 and K1

terminals A1, B1 and C1

terminals D1, E1 and F1

terminals G1, H1, J1 and K1

In the lower IP harness, plugged into the
D206
diode connector breakout
Power and Grounding

G103 On the left front of the #1 crossmember
Component Views
1998 -
UD-lsuzu

The front chassis harness ground, on the
left side of the cab bridge, on the power Power and Grounding
G104 (ABS-Air)
steering reservoir mounting bracket with Component Views

the EBCM
Power and Grounding
G105 On the left front of the #1 crossmember
Component Views
From the front chassis harness, on the left
Power and Grounding
G107 frame rail, approximately 25 cm (9.8 in) to
Component Views
the rear of the front shock absorber
From the engine harness, to the power

Power and Grounding
G108 (Hydraulic Brakes) brake booster pump housing, to the left of
Component Views
the brake master cylinder
G111
On the left frame rail, on the front of the Power and Grounding
belly band Component Views

The ground wire, on the front of the right Power and Grounding
G114
frame rail to the right front of the cab Component Views

From the engine harness, on the left frame Power and Grounding
G118
rail to the generator Component Views

From the engine harness, on the generator Power and Grounding
G119
to the left frame rail Component Views

The ground cable, at the right frame rail to
Power and Grounding
G120 the lower right side of the engine, near the
Component Views
starter
The ground cable, at the right side of the

Power and Grounding
G121 engine, near the starter motor, to the right
Component Views
frame rail
From the lower IP harness, to the upper
G208
right side of the IP
From the lower IP harness, to the upper

G209
right side of the IP
From the lower IP harness, to the right

G210
side of the body

From the right front of the cab to the front Power and Grounding
G214
of the right frame rail Component Views

The negative battery cable to the right Power and Grounding
G400
frame rail Component Views

From the rear chassis and taillamps
harness, to the inboard side of the right Power and Grounding
G404
frame rail, in the ground block, part of the Component Views

negative battery cable
From the trailer harness, to the inboard
Power and Grounding
G405 side of the right frame rail, in the ground
Component Views
block, part of the negative battery cable

G406 (Two-Speed
Rear Axle and Air

Brake Dryer)
From the front chassis and taillamps
G407

1998 -
MD-lsuzu

G408

G501 From the left door harness
G502 From the left door harness
G601 From the right door harness
G602 From the right door harness
On the front chassis harness, under the

Power and Grounding
P100 hood, in the center of the bulkhead, in the
Component Views
cab interface connector housing
On the front chassis harness, under the
Power and Grounding
P101 hood, in the center of the bulkhead, in the
Component Views
cab interface connector housing
On the dash harness, to the A/C
P102
temperature sensor/switch
On the engine controls harness, under the
Power and Grounding
P103 hood, in the center of the bulkhead, to the
Component Views
right of the cab interface connector housing
On the IP harness, under the hood, in the

P201
left side of the bulkhead

P202
center of the bulkhead

P203
right side of the bulkhead

P204
right side of the bulkhead
On the left floor harness, to the door jamb

P300
switch
On the positive battery feed cable, to Power and Grounding

P400
MaxiFuse block 1 Component Views
P401
On the front chassis harness, to Power and Grounding
MaxiFuse block 1 Component Views

On the left door harness, to the lower IP
P501
harness
P502 On the left door harness, in the left door
--

P503 On the left door harness, in the left door
On the right door harness, to the lower IP

P601
harness
P602 On the right door harness, in the right door
P603 On the right door harness, in the right door
In the dual electric horn harness, behind

8100 (Dual the left side of the front bumper impact bar,

Electric Horns) approximately 17 cm (6.7 in) from the rear

horn connector
In the dual electric horn harness, behind
S101 (Dual the left side of the front bumper impact bar,

Electric Horns) approximately 21 cm (8.3 in) from the rear

horn connector
In the front turn signal harness, in the main
S102 branch, approximately 34 cm (13.4 in) from
the left turn signal breakout
1998 -
MD-lsuzu

Inthe front chassis harness, approximately
8103 7 cm (2.8 in) tothe rear of the main
harness breakout
In the frontchassis harness, approximately
S104 13 cm (5.1 in) from the main harness
breakout
In the front turn signal harness, in the main
8105 branch, approximately 40 cm (15.7 in) from
the left turn signal breakout

In the front chassis harness, approximately
8107
4 cm (1.6 in) to the AB8 harness breakout

8108
11 cm (4.3 in) to the AB8 harness breakout
8110
7 cm (2.8 in) from the brake harness
breakout toward the front turn signal

harness
8111 4 cm (1.6 in) in the power brake booster
motor breakout
In the frontchassis harness, approximately
8117 7 cm (2.8 in) toward P100 from the power
brake booster pump motor breakout

8126 30 cm (11.8 in) to the rear of the starter
harness
8130 17 cm (6.7 in) to the left of the starter
harness breakout
8131
breakout, away from the forward lamps

breakout
8132
breakout, toward the forward lamps

breakout
8150 31 cm (12.2 in) from the brake harness
breakout
8152 5 cm (2.0 in) from the rear of the engine oil
pressure switch breakout

8181 In the front chassis harness
Inthe front chassis harness, approximately

8182 13 cm (5.1 in) to the rear of the engine oil

8183 3 cm (1.2 in) forward of the engine oil

8207 In the upper IP harness
In the lower IP harness, behind the center

8211 of the IP, approximately 16 cm (6.3 in)
above the relay center 2 breakout
1998 -
MD-lsuzu

S212 In the lower IP harness
In the lower IP harness, relay center 1

S214
breakout
In the lower IP harness, in the main

S217
branch, to the right of relay center 1

In the upper IP harness, to the right of the

S219
fuse block harness breakout

S220 In the upper IP harness
In the lower IP harness, in the front

chassis harness breakout, approximately
S225
29 cm (11.4 in) from connector C202

(56 cavities)
In the upper IP harness, approximately
S226 32 cm (12.6 in) from the data link
connector (DLC)
In the upper IP harness, under the IP,
S227 approximately 6 cm (2.4 in) to the left of
the fuse block breakout

In the lower IP harness, inside of the cab,
S228 approximately 20 cm (7.9 in) from C202
(56 cavities)
In the lower IP harness, under the left side
S229
of the IP at P203
In the lower IP harness, under the right

S230 side of the IP, approximately 12 cm (4.7 in)
from P203
In the lower IP harness, in main harness at
S231
fuse center breakout

In the lower IP harness, in main harness at
S232
fuse center breakout

In the lower IP harness, approximately
S233
16 cm (6.3 in) to the left of relay center 2

S234 7 cm (2.8 in) to the right of the fuse block
harness breakout
S235 harness at the HVAC and turn/hazard
flasher module harness

In the lower IP harness, in the IP extension
S236 breakout, approximately 20 cm (7.9 in) from
the main branch

S237 harness at the HVAC and turn/hazard
flasher module harness breakout
1998 -
MD-lsuzu

Inthe lower IP harness, approximately
S238 12 cm (4.7 in) to the right of the relay
center 1 harness breakout


4 cm (1.6 in) to the left of the main
S241
harness breakout, toward the speedometer

breakout
In theupper IP harness, approximately

S243 13 cm (5.1 in) from the IP connector
toward the main harness

8246 In the lower IP harness
In the upper IP harness, in the main

S260
harness at the speedometer breakout


S265 harness, approximately 21 cm (8.3 in) from
the upper IP connector C212 (84 cavities)

In theupper IP harness, approximately

8267 15 cm (5.9 in) to the left of the
speedometer harness breakout

In the upper IP harness, at the
S268
speedometer harness breakout

1998 -
MD-lsuzu

S270 harness, approximately 4 cm (1.6 in) to the
right of the speedometer

In theupper IP harness, in the main

S272
harness, at the joint connector breakout

S273 20 cm (7.9 in) from the differential lock
switch connector
S274 35 cm (13.8 in) from the air suspension
dump switch
S275 21 cm (8.3 in) from the heated mirror
switch connector
S276 37 cm (14.6 in) from the differential lock
switch connector
right of the joint connector breakout
In the lower IP harness, below the IP, at

S278
the fuse block harness breakout

In the lower IP harness, below the IP,
S279 approximately 5 cm (2.0 in) to the right of
the relay center 1 harness breakout

S280
harness, at the frame harness breakout

S281 5 cm (2.0 in) toward relay center 2 from
the upper IP harness breakout

S282 5 cm (2.0 in) toward relay center 2 from
the upper IP harness breakout

In the lower IP harness, in the right side of
S283
the IP, at the IP ground breakout

In the lower IP harness, in the right side of
S284 the IP, approximately 8 cm (3.1 in) to the
right of the joint connector 1 breakout

S286 harness, at the fuse block harness
breakout
S287 harness, approximately 22 cm (8.7 in) to
the right of the fuse block harness breakout

harness, approximately 13 cm (5.1 in) to
S288
the right of the relay center 1 harness

breakout
1998 -
MD-lsuzu

right of the relay center 1 harness breakout

S290 24 cm (9.4 in) from the turn/hazard flasher
module connector
In the lower IP harness, inside of the cab,
S291
at the left headlamp (P201)

S292
harness, at the frame harness breakout

branch, under the right seat, approximately
S293
15 cm (5.9 in) from the park brake module

breakout
8294 branch, at the C200 (56 cavities) and C202
(56 cavities) breakout

S295 branch, at the C200 (56 cavities) and C202
(56 cavities) breakout

relay center 2
relay center 2

the floor harness

the floor harness
1998 -
MD-lsuzu


S342 36 cm (14.2 in) from upper IP connector
C212 (84 cavities)

24 cm (9.4 in) from heated mirror switch
S343
connector C216 (6 cavities) with the lighted

mirror
S345 In the roof harness
S357 In the floor harness
S358 In the floor harness
1998 -
MD-lsuzu

8368 In the roof harness
S373 (ABS-Air) In the lower IP harness
Inthe rear chassis and taillamps harness,

S400 approximately 30 cm (11.8 in) from the
engine harness connectors

at the main branch, approximately 10 cm
S400 (Long Wheelbase)
(3.9 in) from the ground connectors

breakout
at the main branch, approximately 10 cm
S400 (Low Profile)
(3.9 in) from the ground connectors

breakout
S401 approximately 20 cm (7.9 in) from the
engine harness connectors

S401 (Long Wheelbase) at the main branch, approximately 5 cm
(2.0 in) from C410

In the full trailer harness, approximately
S405
100 cm (39.4 in) from the trailer receptacle
S406
7 cm (2.8 in) to the ABS harness breakout

8408 7 cm (2.8 in) to the rear of the ABS relay
breakout
S410
17 cm (6.7 in) from the ABS module

S411 4 cm (1.6 in) to the left of the starter motor
relay breakout
1998 -
MD-ISUZU

In the dual fuel tank harness, on the main
branch, approximately 11 cm (4.3 in) from
8415 (Dual Fuel Tanks)
the fuel sender and the balance pump

control module breakout
In the dual fuel tank harness, on the main
branch, approximately 4 cm (1.6 in) from
S417 (Dual Fuel Tanks)
the fuel sender and the balance pump

control module breakout
In the left
door harness, approximately
S500 15 cm (5.9 in) from P501, toward the
sidemarker lamp breakout

In the right door harness, approximately
S600 31 cm (12.2 in) from the power window
switch
In the moisture ejector and air dryer
S701 harness, approximately 10 cm (3.9 in) back
from the air brake dryer breakout

In the moisture ejector and air dryer
S702 harness, approximately 30 cm (11.8 in)
back from the air brake dryer breakout

In the two-speed axle control harness,
S703 approximately 5 cm (2.0 in) in front of the
relay breakout

tail, stop and turn signal lamps breakout

(2.0 in) from the right taillamp breakout

tail, stop and turn signal lamps breakout

(3.9 in) from the right taillamp breakout
Power and Grounding Component Views

Cell 11: Fuse Block, Front View
1 6 11 14 19 24
|25A] J15A1 |20A
2 7 12 15 20 25
J15A1fl5Al |20g
3 8 13 16 21 26
4 9 17 22
FJ5A1|20A|
5 10 18 23
FJ5A1FJ5A1 0
244535
7998 -
MD-lsuzu
Cell 11 : Fuse Block, Rear View
"BET
0; BC 0 a S[r i
L
-L L.U Uj
^"rT
LUU|
0 3 1-C 0 0 0
0 o a : a:LC a a
S:jf -U
1 :0:
U-1
3:Enid-L r-n~- rp
MM
Ll-l LJj

a a :e SJi; a:e
244479
Power and Grounding Component Views

Fuse/Circuit Breaker Rating Description
1 25A Ignition Switch
2 15A Radio, Cigar Lighter, Body Builder Connector
3 15A Timing and Injection Rate Control System (TICS)
4 15A Glow Plug Relay
5 15A Data Link Connector (DLC), Serial Signal Connector
6 15A Relay Centers, VSS Buffer, I/P, Turn Signal Switch, DRL Relays
7 20A Horn Relay, Turn Signal Switch, Radio, Engine Shutdown Module, Dome Lamp
8 20A Power Window Relay
Multifunction Alarm Module, Relay Center 1, Fuel Injection Pump Control Valve,
9 20A Check Connector, Exhaust Brake Switch, Fuel Tanks, Air ABS Relay, Electronic
Brake Control Module (Hydraulic)
Timing and Injection Rate Control System (TICS), Serial Signal Connector,
10 15A
Check Connector
11 20A LH Turn/Stop Relay
12 25A Auxiliary Relay (Switched)

13 25A Body Builder Connector (Battery Direct)
14 15A LH Headlamps
15 15A RH Headlamps
16 15A Lighting Relays
17
Not Used
18 15A Multifunction Alarm Module (MFAM)
1998 -
MD-lsuzu
Power and Grounding Component Views (cont'd)

Fuse/Circuit Breaker Rating Description
19 15A Taillamp Relay
20 20A A/C Compressor, A/C Condenser Fan

21 20A Windshield Wiper Motor, Windshield Washer Pump
22 20A Heated Mirror Switch, Two-Speed Axle Motor Relay
23 20A Stoplamp Relay, Stoplamp Switch
24 20A Blower Motor Relay

Hazard Flasher, Stoplamp Switch (Air Brake), RH Turn/Stop Relay,
25 20A
Park Brake Switch
26 20A Auxiliary Power Post
Relay Center 1 Relay Center 2
1 2 3
^L
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QftD QQD
85 ^ 86 PT
85 86 85 ^ 86
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85 TV 86
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215317 244518
Legend
Legend
(1) Power Window Relay (1) Engine Stop Relay
(2) Lighting Relay (2) Ignition #3 Relay
(3) Taillamp Relay
(3) Ignition #2 Relay
(4) Fuel Pump Relay (Gas), Fuel Heater (4) Blower Relay
Relay (Diesel)
(5) Ignition #1 Relay
(5) Lighting Relay
(6) Compressor Relay
(6) Park Brake Relay (w/J71 Park Brake),
(7) Condenser Fan Relay
Marker Lamps Relay (Tractor)
(7) ABS Telltale Relay (8) Accessory Relay
(8) Left Turn/Trailer Relay (9) Auxiliary Relay
(9) Right Turn/Trailer Relay (10) Horn Relay
(11) Stoplamp Relay
1998 -
MD-lswu
Visual Identification Diagnostic Information and

Data Link Connector End Views
Procedures
Data Link Connector System Check
Data Link Connector (DLC)
1. Test the Scan Tool operation on a known good
vehicle to make certain that the tool is
operating properly.
^
.
1- 2. Inspect the Horn Circuit Breaker to determine if

*
*)
,
K
~\
-I o it is open. If an open condition exists, Locate
'\ pHHRlHHH^ and Repair the cause of the overload and then
^-\tolG^ ^
Lr-ti-^
Replace the circuit breaker.
3. Inspect grounds G111, G113, G210 or G403 to

make certain that they are clean and tight.
4. Inspect for broken (or partially broken) wire
inside the insulation. This condition could cause
68793 system malfunction but prove to test good in a

12110250 continuity or voltage test with the system
Connector Part disconnected. These circuits may be intermittent
ASM 16F Metri Pack
Information or resistive when in operation. If possible test
150 TNGLS (Black)
for a voltage drop when the system is
Circuit
operational.
Not Used 5. Inspect for proper installation of aftermarket
1-3
electronic equipment which may affect the

4 BLK 411 Ground integrity of other systems.
5-6
Not Used
7 BLU 410 Serial Data Link
8-11
Not Used
12 BRN/WHT 396 ABS Diagnostic
13-14
Not Used
15 LTGRN 409 Serial Data Link
Scan Tool Does Not Communicate with Components (EBCM (Hydraulic))

1. Disconnect the scan tool from the vehicle.

2. Connect the scan tool to a vehicle with the same
1 system.
Refer to the
3. Attempt to establish communications. scan tool
Were communications established? Go to Step 2 instruction manual
Backprobe the DLC using a test lamp from terminal 16 to

2 ground.

3 block and the DLC.
Will the scan tool communicate with the EBCM? System OK Go to Step 4
Backprobe the DLC using a test lamp from terminal 16 to
4 terminal 4.
Repair the open in CKT 411 (BLK) between the DLC and
5 joint connector 1.
Will the Scan Tool communicate with the EBCM? System OK Go to Step 6
1998 -
MD-lsuzu
Scan Tool Does Not Communicate with Components (EBCM (Hydraulic)) (cont'd)
Using a self-powered test lamp, backprobe the DLC from
6 terminal 12 to the EBCM terminal 5.
Repair the open in CKT 396 (BRN/WHT) or CKT 799

7 (TAN/WHT) between the DLC and the EBCM.
Using a self powered test lamp, backprobe the DLC from
8 terminal 12 to terminal 4.
Refer to
Did the test lamp light? Go to Step 9 Antilock Brakes
Repair the short to ground in CKT 396 (BRN/WHT) or

9 CKT 799 (TAN/WHT) between the DLC and the EBCM.
Will the scan tool communicate with the EBCM? System OK
Scan Tool Does Not Communicate with Components (EBCM (Air))

1. Disconnect the scan tool from the vehicle.
2. Connect the scan tool to a different vehicle with the

1 same system.
Refer to the
3. Attempt to establish communications. scan tool
Were communications established? Go to Step 2 instruction manual
1. Using a J 39200 DMM, backprobe the DLC from

terminal 16 to ground.
2 10.0V
2. Measure the voltage.
Was the voltage less than the specified value? Go to Step 3 Go to Step 4

3 block and the DLC.
1. Using a J 39200, backprobe the DLC from

terminal 16 to terminal 4.
4 10.0V
Was the voltage less than the specified value? Go to Step 5 Go to Step 6
Repair the open in CKT 411 (BLK) between the DLC and
5 joint connector 1.
1. Using a J 39200, backprobe the DLC from terminal 7
to the EBCM terminal A3.
6 5.0 n
Was the resistance more than the specified value? Go to Step 7 Go to Step 8
Repair the open in CKT 410 (BLU) or CKT 1921 (DK BLU)
7 between the DLC and the EBCM.
1. Using a J 39200, backprobe the DLC from terminal 7

to terminal 4.
8 10MQ
Was the resistance less than the specified value? Go to Step 9 Go to Step 10
Repair the short to ground in CKT 410 (BLU) or CKT 1921
9 (DK BLU) between the DLC and the EBCM.
1998 -
MD-lsuzu
Scan Tool Does Not Communicate with Components (EBCM (Air)) (cont'd)
1. Using J 39200, backprobe the DLC from
a
terminal 15 to the EBCM terminal B3.

10 5.0ft
Was the resistance more than the specified value? Go to Step 11 Go to Step 12
Repair the open CKT 409 and CKT 1922 (LT GRN)
in
11 between the DLC and the EBCM.
1. Using a J 39200, backprobe the DLC from
terminal 15 to terminal 4.
12 10Mft
2. Measure the resistance. Refer to
Was the resistance more than the specified value? Go to Step 13 Antilock Brakes
Repair the short to ground in CKT 409 and CKT 1922

13 (LT GRN) between the DLC and the EBCM.
Will the scan tool communicate with the EBCM? System OK
Description and Operation Data Link Connector Operation

On Diesel Engine equipped vehicles, the Powertrain
Data Link Connector Description Control Module (PCM), the Transmission Control
Module (TCM),if equipped, and the Electronic Brake
Control Module (EBCM) are accessed by the Scan
Tool through CKT 410 (DK/BLU) or CKT 1921
(DK/BLU) and CKT 409 (LT/GRN) or CKT 1922
(LT/GRN). The scan tool also accesses the PCM
through CKT 448 (WHT) or CKT 679 (WHT/BLK).
r-i r~i
On gasoline powered vehicles, the PCM is accessed
0 0 through CKT 547 (ORN/WHT) and CKT 549
15 14 13 12 11 10 9 (WHT/BLK). The scan tool accesses the EBCM

16
(hydraulic) through CKT 396 (BRN/WHT) on these
8 6 5 4 3 2 1
vehicles and on CKT 799 (TAN/WHT) on diesel
7
powered vehicles.
^ J These communication lines are used to monitor the
modules for diagnostic purposes and to check for
Diagnostic Trouble Codes (DTCs). Voltage is applied
at all times to the DLC through the Circuit Breaker 5.
The DLC is permanently grounded through G 105
and G 113.
432
Data Link Connector Circuit Description
The provision for communicating the Data Link is In hydraulic brake models, the scan tool accesses
Connector (DLC). It is usually located under the the electronic brake control module (EBCM) through
instrument panel and is sometimes covered by a CKT 396 (BRN/WHT) or CKT 799 (TAN/WHT).
plastic cover labeled DIAGNOSTIC CONNECTOR. It
In air brake models, the scan tool accesses the
is used in the assembly plant to receive information
EBCM through the following circuits:
in checking that the engine is operating properly
before it leaves the plant. The connector is also
. CKT 410 (BLU) or CKT 1921 (DK BLU)
used by the service technician to identify stored . CKT 396 (BRN/WHT) or CKT 799 (TAN/WHT)
trouble codes and to read control module data using These communication lines monitor the modules for
a hand held scan tool. diagnostic purposes and inspect for diagnostic
trouble codes (DTCs). Circuit breaker 5 applies
voltage at all times to the data link connector (DLC).
Joint connector 1 permanently grounds the DLC.
7998 -
MD-lsuzu
Inline Harness Connector End Views
Inline Connector C105
( [-} I-1 1
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222657

12084891
12186013

ASM 5F Metri-Pack ASM 5M Metri Pack
Information Information
280 SLD (Gray) 280 SLD (Gray)
Circuit Circuit
A BRN 9 Park Lamp Feed A BRN 9 Park Lamp Feed
Turn Signal Lamp Feed, B

B LT BLU 14 LT BLU 14
Left Front Left Front
Turn Signal Lamp Feed, C

C DK BLU 15 DK BLU 15
Right Front Right Front
D BLK 150 Ground D BLK 150 Ground
E DK GRN 29 Horn Feed E DK GRN 29 Horn Feed
7998 -
MD-lsuzu
L J
1F 1
Il
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C
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nl
^f \^
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^ 1
\- ^ D ^
246476

12129600 12129600
Information

Conn 4F Metri-Pack Information

Conn 4M Metri-Pack
280 SLD (Gray) 280 SLD (Gray)
Circuit Circuit
Air Conditioning Refrigerant Air Conditioning Refrigerant
A LT BLU 203 High Pressure Cut Out A LT BLU 203 High Pressure Cut Out
Switch Feed Switch Feed
DK Air Conditioning Condenser DK GRN / Air Conditioning Condenser

B 1728 B 1728
GRN/WHT Relay Output Coil WHT Relay Output Coil
C DK GRN 603 Low Pressure Cut Out C DK GRN 603 Low Pressure Cut Out
Switch Output Switch Output
Air Conditioning Air Conditioning

D LT GRN/BLK 59 Compressor Clutch D LT GRN/BLK 59 Compressor Clutch
Solenoid Feed Solenoid Feed
^] oiio
n
^ f^^))
ff
95664
3 Way F 3 Way M
Connector Part

Connector Part
Information (GRN) Information
(GRN)
Circuit Circuit
A BLK 242 Ground A BLK 242 Ground
B WHT 241 Signal B WHT 241 Signal
C GRY 284 Shield C GRY 284 Shield
1998 -
MD-lsuzu
C112
n
/
A B C D
-^ ^n D C B A
^
E F G H H G F E
\ -^ y
\^ ^
339146
8 Way M 8 Way F
Connector Part
Connector Part
Information (GRY) Information (GRY)

Circuit Circuit
A BLU/BLK 98 Fuel Temperature Sensor A BLU/BLK 39 Fuel Temperature Sensor
B GRA 75 Shield B GRA 42 Shield
C WHT 73 Engine Speed Sensor C WHT 15 Engine Speed Sensor
D BLK 72 Engine Speed Sensor D BLK 14 Engine Speed Sensor
E BLU/RED 97 Fuel Temperature Sensor E BLU/RED 38 Fuel Temperature Sensor
Engine Coolant Temperature F

Engine Coolant
F BLU/BLK 95 BLU/BLK 36
Sensor Temperature Sensor
Engine Coolant Temperature Engine Coolant
G YEL/BLK 94 G YEL/BLK 35
H
Engine Coolant Temperature H
Engine Coolant
GRN 96 GRN 37
C114
n
A B C D .-,nD C B A
E F G H H G F E
J K L M M L K J
N P R S S R P N
339152
Connector Part 16 Way F Connector Part 16 Way F

Information (GRY) Information
(GRY)
Circuit Circuit
A GRN 78 Cylinder 1 Injector A GRN 20 Cylinder 1 Injector
B GRN 77 Cylinder 1 Injector B GRN 19 Cylinder 1 Injector
C BLU 86 Cylinder 6 Injector C BLU 29 Cylinder 6 Injector
D BLU 85 Cylinder 6 Injector D BLU 28 Cylinder 6 Injector
E GRN/WHT 80 Cylinder 5 Injector E GRN/WHT 22 Cylinder 5 Injector
7998 -
MD-ISUZU
C114 (cont'd)
Connector Part 16 Way F Connector Part

16 Way F
Circuit Circuit
F GRN/WHT 79 Cylinder 5 Injector F GRN/WHT 21 Cylinder 5 Injector
G BLU/WHT 88 Cylinder 2 Injector G BLU/WHT 31 Cylinder 2 Injector
H BLU/WHT 87 Cylinder 2 Injector H BLU/WHT 30 Cylinder 2 Injector
J GRN/RED 83 Cylinder 3 Injector J GRN/RED 25 Cylinder 3 Injector
K GRN/RED 82 Cylinder 3 Injector K GRN/RED 24 Cylinder 3 Injector
L BLU/RED 91 Cylinder 4 Injector L BLU/RED 34 Cylinder 4 Injector
M BLU/RED 90 Cylinder 4 Injector M BLU/RED 33 Cylinder 4 Injector
N RED/BLU 89 Cylinder 4 Injector N RED/BLU 32 Cylinder 4 Injector
P RED/BLU 84 Cylinder 6 Injector P RED/BLU 27 Cylinder 6 Injector
R RED/YEL 81 Cylinder 3 Injector R RED/YEL 23 Cylinder 3 Injector
S RED/YEL 76 Cylinder 1 Injector S RED/YEL 17 Cylinder 1 Injector
0
A B C D n D C B A
E F G H H G F E
J K L M M L K J
339150

12 Way M
Circuit Circuit
Injection Pump Speed Injection Pump Speed
A GRN 68 A GRN 11
Sensor Sensor
B WHT 63 Fuel Pressure Sensor B WHT 8 Fuel Pressure Sensor
C BRN/BLK 55 Pressure Control Valve 2 C BRN/BLK 5 Pressure Control Valve 2
D GRN 8 Pressure Control Valve 1 D GRN 1 Pressure Control Valve 1
Injection Pump Speed Injection Pump Speed
E RED 69 E RED 12
Sensor Sensor
F RED 64 Fuel Pressure Sensor F RED 9 Fuel Pressure Sensor
G BRN/BLK 56 Pressure Control Valve 2 G BRN/BLK 6 Pressure Control Valve 2
H BRN 53 Pressure Control Valve 1 H BRN 3 Pressure Control Valve 1
J GRA 71 Shield J GRA 41 Shield
K GRA 67 Shield K GRA 40 Shield

L BLK 62 Fuel Pressure Sensor L BLK 7 Fuel Pressure Sensor
M BRN 54 Pressure Control Valve 1 M BRN 4 Pressure Control Valve 1
1998 -
MD-lsuzu
r^^\
/BBBBI-]
[BBBBJ
3
4
5
6
n
7
8
9
10
^\
^^ 339145
Connector Part 12186024 Connector Part 7322748440

Information ASM 8F SWP SLD (Gray) Information 8 Way M (Gray)
Circuit Circuit
3 PNK 39 Fuse Output-Ignition 3 BRN/WHT 9 Fuse Output-Ignition
Coolant Temperature
4 DK GRN 135 4
Not Used
Sensor Signal
Charge Indicator Charge Indicator
5 BRN 25 5 BRN 5
Lamp Output Lamp Output
Air Conditioning Air Conditioning

6 DKGRN 59 Compressor Clutch 6 GRN 6 Compressor Clutch
7 TAN/WHT 331 Oil Pressure Sensor Signal 7 BRN/WHT 7 Oil Pressure Sensor Signal
Alternator Output Regulator Alternator Output Regulator

8 RED 225 8 RED 8
Reference Voltage Reference Voltage
Coolant Temperature Coolant Temperature
9 GRY 535 9 GRY 11
10
Not Used 10
Not Used
cue
jiniL
BSB
BEE
v
229954
12162918 2 Way M

Information 2 Way F (GRY) Information (GRY)

Circuit Circuit
1 RED 503 Glow Plug 1 RED 2 Glow Plug
2
Not Used 2
Not Used
1998 -
MD-lsuzu
I
\J\.
339140
2 Way 2 Way
Connector Part

Connector Part
Information
Female Information Male
Circuit Circuit
A BLU 31 Starter A RED Starter
BLU 32 Starter RED 3 Starter
13H @3@
SS
BB IOE
@3@|@
as
g6|[45]@4]
BOI]
|(^[)9](18]
[IE
Q51[16][17] @IEi[4i] [iTiEiiiii
IIOIIIH 13](14] HI: |40)|39||3|37||3(|
[14][13](12][H]|10]
ELimJ}[9] [J1]|J ll^^lilll [EllBLllLl]
229955
Connector Part 56 Way Connector Part

12162883
Information
Female Information
ASM CONN 56M (WHT)
Circuit Circuit
1 RED 8 Battery Output Unfused 1 RED 842 Battery Output Unfused
2 RED 9 Fuse Output Battery 2 RED 1342 Fuse Output Battery

3 BLK 21 Ground 3 BLK 550 Ground
Ignition Switch Output Ignition Switch Output
5 YEL 33 5 YEL 5
Crank Crank
Transmission Mounted Transmission Mounted

6 ORN/BLK 487 Neutral Safety Switch 6 ORN/BLK 434 Neutral Safety Switch
Signal Signal
Generator Indicator
7 BRN/WHT 35 7 PNK 39 Fuse Output-Ignition
Lamp Output
Fuse Output Generator Fuse Output Generator
8 YEL 37 8 YEL 53
Tachometer Pulse Tachometer Pulse
1998 -
MD-ISUZU
Inline Connector C200 (cont'd)
Connector Part 56 Way Connector Part

12162883
Information
Female Information
ASM CONN 56M (WHT)
Circuit Circuit
Generator Indicator Generator Indicator L-
9 BRN 38 9 BRN 25
Lamp Output amp Output
Generator Indicator
10 WHT 702 10
Not Used
Lamp Output
11-14
Not Used 11-14

Not Used

15 GRY 65 15 GRY 535
16-17
Not Used 16-17
Not Used
18 GRN 172 Horn Feed 18 GRN 29 Horn Feed
Stop/Turn Lamp Feed, Stop/Turn Lamp Feed,
19 YEL 134 19 YEL 18
Left Rear Left Rear

20 CRN 135 20 GRN 19
Right Rear Right Rear
21 BRN 24 Park Lamp Feed 21 BRN 9 Park Lamp Feed
22 PNK 145 Fuse Output Ignition 22 PNK 139 Fuse Output Ignition
23
269 Shift Solenoid Feed 23 BRN 323 Shift Solenoid Feed
24 BLK/WHT 272 Engine Brake Enable Signal 24 PPL 1146 Engine Brake Enable Signal
Suspension Dump Valve Suspension Dump Valve
25 BLU 622 25 BLU 1944
26
Not Used 26
Not Used
27 LT BLU 208 High Pressure Cut Out 27 LT BLU 203 High Pressure Cut Out
Air Conditioning Condenser Air Conditioning Condenser
28 GRN/WHT 205 28 GRN/WHT 1728
Relay Output Coil Relay Output Coil
29 GRN 206 Low Pressure Cut Out 29 GRN 603 Low Pressure Cut Out
Air Conditioning Condenser Air Conditioning Condenser
30 BLU/WHT 202 30 BLU/WHT 1727
Fan Motor Feed Fan Motor Feed
Dash Lamp Relay Dash Lamp Relay
31 BLU 407 31 BLU 1899
Output Coil Output Coil
32
Not Used 32
Not Used
ABS Failure Indicator ABS Failure Indicator
33 LT GRN 391 33 LT GRN 867
Dash Lamp Relay Dash Lamp Relay
34 BLU 395 34 BLU 1899
Output Coil Output Coil
Diagnostic Signal Diagnostic Signal
35 BRN/WHT 396 35 BRN/WHT 799
ABS5208V ABS5208V
Brake Warning Indicator Brake Warning Indicator
37
Not Used 37
Not Used
38 LT GRN 481 Low Coolant Sensor Signal 38 LT GRN 1478 Low Coolant Sensor Signal
39
Not Used 39
Not Used
Brake Warning Indicator Brake Warning Indicator
7998 -
MD-ISUZU

Connector Part

12162883
Information
Female Information ASM CONN 56M (WHT)
Circuit Circuit
Brake Booster Fluid Flow Brake Booster Fluid Flow
41 LT BLU 475 41 LT BLU 1928
Brake Pedal Switch Output Brake Pedal Switch Output

42 GRY/BLK 489 42 GRY/BLK 847
Extended Travel Extended Travel
Brake Pedal Switch Output Brake Pedal Switch Output
43 WHT 493 43 GRY 847
Extended Travel Extended Travel
44 GRN 322 Body Builder Connector 44 GRN 909 Body Builder Connector
45-50
Not Used 45-50
Not Used
51 BLU 323 Body Builder Connector 51 BLU 910 Body Builder Connector

52 GRN 385 52 GRN 135
Sensor Signal Sensor Signal
53 PPL 386 Fuel Gauge Sensor Signal 53 PPL 30 Fuel Gauge Sensor Signal
54 BRN/WHT 383 Oil Pressure Sensor Signal 54 BRN/WHT 331 Oil Pressure Sensor Signal
Oil Pressure Indicator Oil Pressure Indicator
55 BRN 382 55 BRN 31
56
Not Used 56
Not Used
[21]I22||2; t8||4||5i[5l]
[18][19]|2( |46|[45][44] |20][]9][l8]
[III]
>^
tuiniii?7\ LJ
[iol[i]][ij
?](13][14]
[3<|i
[3]B BOI]
|43]|42|(41] [r7JIl6][l5]
[l4][l3|[l2][[[|[lo]
|40][39|[38]^7]|36|
UlEl]
[5][6][7][8][9] [31]| [9][8][7][6][5]

|35]|34J[33][32][31]
240000
Connector Part


12162881
Information
Female Information
ASM CONN 56M (Gray)
Circuit Circuit
Brake Pedal Switch Brake Pedal Switch

5 BRN 651 5 BRN 848
Signal ABS Signal ABS
6-14
Not Used 6-14
Not Used
15 BLK 245 Ground-Clean 15 BLK/WHT 351 Ground-Clean
18
Not Used 18
Not Used
1998 -
MD-lsuzu

Connector Part
12162881
Information
Female Information
ASM CONN 56M (Gray)
Circuit Circuit
Turbo Charger Boost Turbo Charger Boost
19 WHT 258 19 WHT 900
Pressure Signal Pressure Signal
Reference Voltage Feed- Reference Voltage Feed-
20 RED 259 20 GRA 596
5 Volt Reference 5 Volt Reference
21 WHT/BLK 679 Fuse Output Accessory 21 WHT/BLK 448 Fuse Output Accessory
21
Not Used 21
Not Used
22 BLK 260 Sensor Return 22 BLK 808 Sensor Return

23 GRA 263 Drain Wire Return 23 BARE 1782 Drain Wire Return
24-30
Not Used 24-30
Not Used
Two Speed Rear Axle Shift Two Speed Rear Axle Shift
32 GRY/BLK 416 32 GRY/BLK 1467
Motor Relay Output Coil Motor Relay Output Coil
Vehicle Speed LT GRN/BLK
Vehicle Speed
33 LT GRN/BLK 426 33 822
Sensor Return Sensor Return
Vehicle Speed Vehicle Speed
33 LT GRN/BLK 431 33 LT GRN/BLK 822
34 PPL/WHT 425 34 PPL/WHT 821
36
Not Used 36
Not Used
37 ORN 321 Fuse Output Battery 37 ORN 640 Fuse Output Battery
38
Not Used 38
Not Used
Turn Signal Lamp Feed, Turn Signal Lamp Feed,
40 LT BLU 136 40 LT BLU 14
Left Front Left Front
41 WHT 105 Stop Lamp Switch Output 41 WHT 17 Stop Lamp Switch Output
42
Not Used 42
Not Used
Turn Signal Lamp Feed, Turn Signal Lamp Feed,
43 DK BLU 139 43 DK BLU 15
Right Front Right Front
Trailer Relay Output (N.O.) Trailer Relay Output (N.O.)

44 YEL 116 Contact, Left Rear 44 YEL 318 Contact, Left Rear
Stop/Turn Lamp Stop/Turn Lamp
Trailer Relay Output (N.O.) Trailer Relay Output (N.O.)

45 GRN 111 Contact, Right Rear 45 GRN 319 Contact, Right Rear
46-48
Not Used 46-48
Not Used
Serial Data Link B Serial Data Link B
49 LTGRN 409 49 LT GRN 1922
SAE 1708 SAE 1708
Serial Data Link A Serial Data Link A
50 BLU 410 50 BLU 1921
SAE 1708 SAE 1708
51-56
Not Used 51-56
Not Used
1998 -
MD-lsuzu
0= ^nll J 57
\
&
I
I
BB 59 ]
58
229956
Connector Part 12162885 Connector Part

7147586530
Information ASM 3F (Natural) Information ASM 3M (NAT)
Circuit Circuit
[n
-d
<-^")
\- 1
1 -3 E
a D
3
2
2
D=. <-"
-i i i
239989
12162873 2 Way M
Connector Part

Connector Part
Information ASM 2F (BLU) Information (BLU)

Circuit Circuit
Power Brake Booster Pump Power Brake Booster Pump

2 RED 1470 2 RED 474
Motor Feed Motor Feed
1998 -
MD-lsuzu
A B B A
[ ] [ ]
C D E F E D C
<^
339126
6 Way F 6 Way M
Connector Part

Connector Part
Information (BLK) Information (BLK)
Circuit Circuit
A RED 156 Dome Lamp A RED 3 Dome Lamp
B RED/YEL 149 Dome Lamp B RED/YEL 2 Dome Lamp
C BRN 98 ID Clearance Lamp C BRN 5 ID Clearance Lamp
D
Not Used D
Not Used
E BLK 25 RH Clearance Lamp E BLK 4 RH Clearance Lamp
'
F ORN 150 Dome Lamp F ORN 1 Dome Lamp
II
Li][6][I] [UnQEll cam as a I4] BBS
[161[15][1I1 QI] [12]OLD
BO] 00 [8]
Y
BE SLi]@[i3 [wll^lB
-/
238853
Connector Part 16 Way F Connector Part 16 Way M

Information . (BLK) Information (BLK)
Circuit Circuit
1-2
Not Used 1-2
Not Used
Automatic Transmission Automatic Transmis sion

3 GRA 65 Selector Control 3 LTBLU 745 Selector Control
(Manual Only) (Manual Only)
4 RED/BLK 26 Door Jamb Switch 4 RED/BLK 148 Door Jamb Switch
5 ORN 8 Trailer Stop Lamp Switch 5 ORN 108 Trailer Stop Lamp Switch
5 ORN 8 Trailer Stop Lamp Switch 5 ORN 536 Trailer Stop Lamp Switch
6
Not Used 6
Not Used
Trailer Stop Lamp Trailer Stop Lamp

7 WHT 9 7 WHT 109
1998 -
MD-lsuzu
Connector Part

16 Way F Connector Part
16 Way M
Circuit Circuit
Trailer Stop Lamp Trailer Stop Lamp
7 WHT 9 7 YEL/BLK 523
8-9
Not Used 8-9
Not Used
10 BRN 76 Shift Selector 10 BRN 99 Shift Selector

11 BLK 16 Consent(C213) 11 BLK 27 Consent(C213)
12 GRN/RED 15 Consent(C213) 12 GRN/RED 157 Consent(C213)
13
Not Used 13
Not Used
Automatic Transmission Automatic Transmission

14 BRN/RED 73 Selector Control 14 BLK/RED 100 Selector Control
(Manual Only) (Manual Only)
15-16
Not Used 15-16

Not Used
n r "I
/
\ /' \
A B C D D C B A
E F G H H G F E
\ \, -^ V }
^
339146
8 Way F 8 Way F
Connector Part

Connector Part
Circuit Circuit
A BLU/RED 452 Washer Pump A BLU/RED 6 Washer Pump
B BLU/ORN 453 Washer Pump B BLU/ORN 7 Washer Pump
C
Not used C
Not Used
D BLU/WHT 255 ATM Temperature Sensor D BLU/WHT 20 ATM Temperature Sensor
E LTGRN 214 Switch, Thermal E LT GRN 16 Switch, Thermal
F GRN/YEL 215 Switch, Thermal F GRN/YEL 17 Switch, Thermal
G GRN/RED 213 Switch, Thermal G GRN/RED 18 Switch, Thermal
H BLU/BLK 214 ATM Temperature Sensor H BLU/BLK 21 ATM Temperature Sensor
1998 -
MD-lsuzu
A1 r^C'OT'n nDDnm A12 A12 DDDCnrinnnrnn AI

ULiLjujrinrinoDD
OCX30DDOODOOO
DO DCinn
DDDCj 0 nDDDDO
mmm
CD BUBlULJ DO rûu
DO o DO DO DG
DO 2dQQ DD 1 Inn
DOQCjLJLJ lH-JIlHHl
1 11 11 H
r~innf~mn
-inn
LJI1111) lIL-HJIHK)
J1 J12 J12
229957
Connector Part
73221474 Connector Part
73231567
Information
84 Way F (WHT) Information
84 Way M (WHT)
Circuit Circuit
A1 GRY 635 Do Not Shift Indicator Lamp A1 GRY 7 Do Not Shift Indicator Lamp
A2 BRN 382 Do Not Shift Indicator Lamp A2 BRN 8 Oil Indicator Lamp
A3 BRN/WHT 383 Oil Pressure Gauge A3 BRN/WHT 211 Oil Pressure Gauge
A4-A5
Not Used A4-A5
Not Used
Service Engine Soon Service Engine Soon
A6 BRN/WHT 248 A6 BRN/WHT 36
Indicator Lamp Indicator Lamp
A7 BRN/YEL 220 A/C Mode 6 A7 BRN/YEL 199 Mode 6

A8 BRN/GRN 221 A/C Mode 5 A8 BRN/GRN 200 Mode 5
A9 BRN 222 A/C Mode 4 A9 BRN 192 Mode 4
A10 BRN/WHT 223 A/C Mode 3 A10 BRN/WHT 191 Mode 3

AH LT GRN/BLK 224 A/C Mode 8 A11 LT GRN/BLK 198 Mode 8
A12 LT GRN/YRL 225 A/C Mode 7 A12 LT GRN/YEL 197 Mode 7

B1
Not used B1
Not Used
B2 GRN 257 Water Temp Gauge B2 GRN 23 Water Temperature Gauge
B3 PPL 386 Fuel Gauge B3 PPL 24 Fuel Gauge
B4 WHT 250 Tachometer Signal B4 WHT 30 Tachometer Pulse
B5 BLK 388 Tachometer Ground B5 BLK 31 Tachometer Ground
B6 PPL/WHT 235 R/F Actuator ON B6 PPL/WHT 178 R/F Actuator ON
B7 BRN/BLU 226 A/C Mode 1 B7 BRN/BLU 189 Mode 1
B8 BRN/BLK 227 A/C Mode 8 B8 BRN/BLK 190 Mode 2
LT
B9 229 A/C Temp 2 B9 LT GRN 188 Temp 2
GRN/WHT
B10 LT GRN 229 A/C Temp 2 B10 LT GRN 196 Temp 2
B11 PNK 230 A/C Temp 4 B11 PNK 187 Temp 5
B12 PNK/BLU 231 A/C Temp 5 B12 PNK/BLU 194 Temp 5
C1
417
C1
151
C2 LT GRN 404 ABS Indicator Lamp C2 LTGRN 38 ABS Indicator Lamp

C2 LT GRN 392 ABS Indicator Lamp C2 LTGRN 38 ABS Indicator Lamp
Left Turn Signal Left Turn Signal
C3 LT BLU 142 C3 LT BLU 17
Right Turn Signal Right Turn Signal
C4 BLU 140 C4 BLU 18
1998 -
MO-lsuzu
Connector Part

73231567
Information
84 Way F (WHT) Information
84 Way M (WHT)
Circuit Circuit
C5
Not Used C5
Not Used
C6 RED/YEL 82 High Beam Indicator Lamp C6 RED/YEL 14 High Beam Indicator Lamp
C7 PNK/BLU 232 A/C Temp 3 C7 PNK/BLK 195 A/C Temp 3
C8 PPL/YEL 233 A/C Recirculate ON C8 PPL/YEL 175 A/C Recirculate ON
C9 PPL/GRN 234 A/C Recirculate OFF C9 PPL/GRN 176 A/C Recirculate OFF
HVAC Fan Medium/High HVAC Fan Medium/High
C10 BLU/YEL 194 C10 BLU/YEL 182
Resistor Resistor
HVAC Fan Medium/Low HVAC Fan Medium/Low
C11 BLU/BLK 195 C11 BLU/BLK 181
Resistor Resistor
C12 BLU/WHT 196 HVAC Fan Low C12 BLU/WHT 180 HVAC Fan Low Resistor
D1 GRN 175 Side Marker Lamp D1 GRN 111 Marker Lamp Switch
D2 ORN 176 Side Marker Lamp D2 ORN 112 Marker Lamp Switch
D11 LTGRN 197 Ignition D11 LT GRN 171 Ignition
D12 BLU/RED 192 HVAC Fan High D12 BLU/RED 183 HVAC Fan High
E1 BRN 95 Illumination (+) E1 BRN 2 Tail
E2 ORN 342 Heated Mirror Switch E2 ORN 142 Heated Mirror

E11 GRN 216 A/C Condenser Fan Control E11 GRN 177 A/C Condenser Fan Control
Air Suspension Dump Air Suspension Dump
E12 PNK 621 E12 PNK 121
Switch Switch
F1 PNK 341 Heated Mirror Switch F1 PNK 141 Heated Mirror
F2 BRN 371 Fuse Output Ignition F2 BRN 1 Fuse Output Ignition
F11
Not Used F11
Not Used
F12 BLK/ORN 26 Ground F12 BLK/ORN 160 Ground Bus

G1
Not Used G1
Not Used
Exhaust Brake Exhaust Brake

G2 BLK/WHT 278 G2 BLK/WHT 90
G3
Not Used G3
Not Used
G4 BLU/YEL 273 Exhaust Brake Switch G4 BLU/YEL 82 Exhaust Brake Switch

G5 WHT 669 Exhaust Brake Switch G5 WHT 83 Exhaust Brake Switch
G6 GRN/WHT 356 Speaker, Right G6 GRN/WHT 156 Speaker, Right
G7
254 Not Used G7
Not Used
Service Park Brake Service Park Brake

G8 BLK/WHT 511 G8 BLK/WHT 13
Apply Park Brake Apply Park Brake

G9 LTGRN 512 G9 LTGRN 11
Apply Park Brake Apply Park Brake

G10 BLU 513 G10 BLU 12
G11
253 Not Used G11
Not Used
Primary Brake Primary Brake
G12 BRN/WHT 494 G12 BRN/WHT 9
Primary Brake Primary Brake

G12 BRN/WHT 606 G12 BRN/WHT 9
H1 BRN
Speedometer (+) H1
45 Not Used
H2 BLK 423 Ground H2 BLK 43 Ground
1998 -
MD-lsuzu
S-244 Wiring Systems Body and Accessories
Connector Part
73231567
Information 84 Way F (WHT) Information 84 Way M (WHT)
Circuit Circuit
Vehicle Speed Sensor Vehicle Speed Sensor
H3 WHT 422 H3 WHT 42
Signal (B8) Signal (B8)
H4
Not Used H4
Not Used
H5 BLU/WHT 358 Speaker, Left H5 BLU/WHT 158 Speaker, Left

H6 GRN 355 Speaker, Right H6 GRN 155 Speaker, Right
H7 BRN 465 Coolant Temperature Switch H7 BRN 33 Check Gauge Logic (6H)
H7 BRN 609 Coolant Temperature Switch H7 BRN 33 Check Gauge Logic (6H)
H8 BRN/BLK 466 Low Oil Pressure Switch H8 BRN/BLK 34 Check Gauge Logic (6H)
H8 BRN/BLK 610 Low Oil Pressure Switch H8 BRN/BLK 34 Check Gauge Logic (6H)
H9 BLK 672 Fast Idle Switch H9 BLK 102 ECU (29)
H10 RED 251 Fast Idle Switch H10 GRN 101 Fast Idle Switch
Air Suspension Dump Air Suspension Dump
H11 BLU 622 H11 BLU 122
Switch Switch
H12 PPL 542 Differential Lock Switch H12 PPL 132 Differential Lock Switch
Service Trans Filter Service Trans Filter

J1 RED J1 RED
Engine Overspeed Engine Overspeed

J2 BRN/YEL 578 J2 BRN/YEL 71
J3
Not Used J3
Not Used
J4 LT BLU 712 Intake Heater panel Lamp J4 LT BLU 66 Intake Heater Panel Lamp
J5 BLU 357 Speaker, Left J5 BLU 157 Speaker, Left
J6 RED 670 Fast Idle Indicator Lamp J6 RED 64 Fast Idle Indicator Lamp
Interior Lamps Interior Lamp
J7 BLK/RED 100 J7 BLK/RED 39
Dimming Buss Dimming Buss
J8 BRN 38 Generator Indicator Lamp J8 WHT 6 Generator Indicator Lamp

Daytime Running Lights Daytime Running Lights
J9 BLU 724 J9 BLU 59
J10 YEL/RED 483 Low Coolant Indicator Lamp J10 YEL/RED 15 Low Coolant Indicator Lamp
J10 YEURED 603 Low Coolant Indicator Lamp J10 YEL/RED 15 Low Coolant Indicator Lamp
J11 YEL/BLK 484 Aux Brake Indicator Lamp J11 YEL/BLK 10 Aux Brake Indicator Lamp
Check Gauges Check Gauges
J12 BLU/YEL 607 J12 BLU/YEL 19
Check Gauges Check Gauges

J12 BLU/YEL 488 J12 BLU/YEL 19
1998 -
MD-ISUZU
n n
B B
A A
339143
2 Way F 2 Way M
Connector Part
Connector Part
Information (NAT) Information (NAT)
Circuit Circuit
A GRN 15 Auxiliary Power Post Feed A GRN 1 Auxiliary Power Post Feed
Auxiliary Power Post Auxiliary Power Post

B BLK 16 B BLK 2
Ground Ground
1 1
-^-Lr i
1
(c B E
\
&<B]
0 B
v
&Q J \-
\^
y
,/
62458

12064760 12064761

ASM 4F Metri Pack ASM 4M Metri-Pack
150 (Black) 150 (Black)
Circuit Circuit
Multi-Function Alarm Module Multi-Function Alarm
A LT BLU 252 A LT BLU 66
(Engine Shutdown) Module (Engine Shutdown)
B-C
Not Used B-C
Not Used
D
Engine Coolant Temperature D
GRY 65
Not Used
Signal
1998 -
MD-ISUZU
Inline Connector C215 (With/Without Electric Park Brake)
1 1 r) ^-f(
r~~
(C BB
\
)
&Q
B B
J Y
&^] y
v^
\- }
339125
4 Way F 4 Way M
Connector Part
Connector Part
Circuit Circuit
A
Not Used A BLK 535 Park Brake Switch
A BLK 521 Park Brake Conn. (Mech.) A BLK 535 Park Brake Switch
B ORN 516 Park Brake Conn. (Elec.) B ORN 533 Park Brake Switch
B BLU 520 Park Brake Conn. (Mech.) B ORN 533 Park Brake Switch
C YEL/BLK 517 Park Brake Conn. (Elec.) C YEL/BLK 534 Park Brake Switch
C
Not Used C YEL/BLK 534 Park Brake Switch
D ORN 522 Park Brake Conn. (Elec.) D ORN 536 Park Brake Switch
D PNK 537 Park Brake Conn. (Mech.) D ORN 536 Park Brake Switch
C217
,-G
1 S
F
R
E
P N |M
D
L
C
K
B
J 4 [BB
A
J
C
K
D
L M N
E
P
F
R
G
S

I
<^
339155
Connector Part
16 Way F Connecto Part
r

16 Way M
Information (BLK) Informa tion (BLK)
Circuit Circuit
A BLK 57 Ground A BLK 246 Ground
B BLK 59 Ground B BLK 245 Ground
C BLU/BLK 93 ATM Temperatur e Sensor C BLU/BLK 256 ATM Temperature Sensor
D BLU/YEL 42 Clutch Switch D BLU/YEL 277 Clutch Switch
E RED 9 Fuse Output-Ignition E RED 240 Fuse Output-Ignition
F BLU/WHT 92 ATM Temperatur e Sensor F BLU/WHT 255 ATM Temperature Sensor
1998 -
MD-lsuzu
C217 (cont'd)

16 Way M
Information (BLK) Information . (BLK)
Circuit Circuit
IP Cluster (Service IP Cluster (Service
G BRN/WHT 16 G BRN/WHT 248
Engine Soon) Engine Soon)
H RED 1 Ignition Main Relay H RED 242 Ignition Main Relay
J BLK 101 Fuel Pressure Sensor J BLK 260 Fuel Pressure Sensor
K GRA 103 Shield K GRA 262 Shield
L YEL 49 Ignition Switch L YEL 243 Ignition Switch
ECM Pin 29 (Fast Idle Plugged at C212

M PNK/BLK 35 M PNK/BLK 253
Switch Down) (Upper Facia)
ECM Pin 10 (Fast Idle Plugged at C212
N PNK/GRN 34 N PNK/GRN 254
Switch Up) (Upper Facia)
P
Turbo Boost Pressure P
Turbo Boost Pressure
RED 100 RED 259
Sensor Sensor
Turbo Boost Pressure Turbo Boost Pressure
R WHT 99 R WHT 258
Sensor Sensor
S
Not Used S
Not Used
C218
J! 111' A! I'
><1
-r- :JK M
^
X
339151
Connector Part
20 Way F Connector Part
20 Way M
Circuit Circuit
A
Not Used A
Not Used
B LTGRN 28 Data Link Connector B LT GRN 264 Data Link Connector
C
Not Used C
Not Used
Automatic Transmission Automatic Transm ission

D RED/BLK 50 D RED/BLK 268
Modulator Relay Modulator Relay
E
Not Used E
Not Used
F GRA 113 Accelerator Pedal Sensor F GRA 285 Accelerator Pedal Sensor
G BLK 38 Accelerator Pedal Sensor G BLK 283 Accelerator Pedal Sensor
H WHT 36 Accelerator Pedal Sensor H WHT 281 Accelerator Pedal Sensor
J RED 37 Accelerator Pedal Sensor J RED 282 Accelerator Pedal Sensor
K BLK 61 Ground K BLK 280 Ground
L BLU 29 Data Link Connector L BLU 265 Data Link Connector
1998 -
MD-lsuzu
C218 (cont'd)
Connector Part 20 Way F

Connector Part

20 Way M
Circuit Circuit
Multifunction Alarm Module Multifunction Alarm Module
M LT BLU 20 C2 w/ Auto Engine M LT BLU 252 C2 w/ Auto Engine
Shutdown Shutdown
N WHT 19 IP Cluster(Tach.) N WHT 250 IP Cluster(Tach.)
Engine Coolant Engine Coolant

P CRN 96 P GRN 257
Temperature Sensor Temperature Sensor
R BLU/YEL 52 Exhaust Brake Relay R BLU/YEL 275 Exhaust Brake Relay
S
Not Used S
Not Used
T GRA 116 Accelerator Pedal Sensor T GRA 291 Accelerator Pedal Sensor
U BLU 41 Accelerator Pedal Sensor U BLU 289 Accelerator Pedal Sensor
W GRN 39 Accelerator Pedal Sensor W GRN 287 Accelerator Pedal Sensor
x YEL 40 Accelerator Pedal Sensor X YEL 288 Accelerator Pedal Sensor
C219
,-F'TL -^T-
[H B B [B]
246493
2 Way 2 Way
Connector Part
Connector Part
Information
Female Information
Male
Circuit Circuit
Two Speed Rear Axle Two Speed Rear Axle
A GRA/BLK 21 A GRA/BLK 416
Switch Switch
Automatic Transmission Automatic Transmission
B GRN 68 Selector Control B GRN 642 Selector Control
(MD Trans Only) (MD Trans Only)
1998 -
MD-lsuzu
^ -ULr-ir-i
C1/
B1
A1 \ ^ M&fs DDDD LCS C5DDDDD

B5DDDDC]B1
A5DDDDD l
"J
]
243495

12161186 12161187
Connector Part Connect or Part

ASM 15F Metri-Pack ASM 15M Metri-Pack
Information Inform ation
280 SLD (Black) 280 SLD (Black)
Circuit Circuit
DK ABS Wheel Speed Sensor DK ABS Wheel Speed Sensor
A1 1911 A1 1911
BLU/WHT Signal Left Rear BLU/WHT Signal Left Rear
DK ABS Wheel Speed Sensor DK ABS Wheel Speed Sensor

A2 1912 A2 1912
GRN/WHT Return Left Rear GRN/WHT Return Left Rear
ABS Modulator Output ABS Modulator Output
A3 GRY 1913 A3 GRY 1913
Exhaust Left Rear Exhaust Left Rear
ABS Modulator Output Hold ABS Modulator Output Hold
A4 LT BLU/BLK 1914 A4 LT BLU/BLK 1914
Left Rear Left Rear
ABS Modulator Feed ABS Modulator Feed

A5 ORN 1915 A5 ORN 1915
Left Rear Left Rear
ABS Wheel Speed Sensor ABS Wheel Speed Sensor

B1 LT GRN/BLk 1916 B1 LT GRN/BLk 1916
Signal Right Rear Signal Right Rear
LT ABS Wheel Speed Sensor LT ABS Wheel Speed Sensor
B2 1917 B2 1917
BLU/WHT Return Right Rear BLU/WHT Signal Right Rear
ABS Modulator Exhaust ABS Modulator Exhaust

B3 LTGRN 1918 B3 LTGRN 1918
ABS Modulator Output Hold ABS Modulator Output Hold
B4 PNK/BLU 1919 B4 PNK/BLU 1919
ABS Modulator Feed ABS Modulator Feed

B5 PPL 1920 B5 PPL 1920
C1-C5
Not Used C1-C5
Not Used
1998 -
MD-lsuzu
E H
w L ^
\J
L^3a dlifh D
/ffnfrG
IA: B
F
C )
1"- >r
/
-
^
-
n ii i ii
^ ~\.
229958

12047937 12047931
8 Way F Metri-Pack Information
8 Way M Metri-Pack
Information
150 Series, Sealed (BLK) 150 Series, Sealed (BLK)
Circuit Circuit
A BRN 9 Park Lamp Feed A BRN 9 Park Lamp Feed
B LT GRN 24 Back Up Lamp Feed B LTGRN 24 Back Up Lamp Feed
Stop/Turn lamp Feed, Stop/Turn Lamp Feed,
C YEL 18 C YEL 18
Left Rear Left Rear

D DK GRN 19 D DKGRN 19
E
Not Used E GRA 120 Fuel Pump Motor Feed
F PPL 30 Fuel Gauge Sensor Signal F PPL 30 Fuel Gauge Sensor Signal
Two Speed Rear Axle Shift Two ^P601 Rear Axle S"^
G GRY/BLK 1467 G GRY/BLk 14R7
Motor Relay Output Coil Motor Relay Output Coil
Suspenskon Dump Valve Suspension Dump Valve
H DK BLU 1944 H DK BLU --..
C404
ft
rn-i
^ &OL&OLS: I))
-^
ft3BEn
95864

12040977 15300003
3 Way F Metri-Pack 3 Way M Metri-Pack
280 Series, Sealed (BLK) 280 Series, Sealed (BLK)
Circuit Circuit
A PNK 239 Fuse Output-Ignition A BRN 241 Fuse Output-Ignition
B PNK 139 Fuse Output-Ignition B BRN 341 Fuse Output-Ignition
C
Not Used C
Not Used
1998 -
MD-lsuzu
C406
39743
12110751
12110753
Metri-Pack Connector Part
7 Way M Metri-Pack
Information 280 Series, Flexlock, Information
280 Series, Sealed (BLK)
Sealed (BLK)
Circuit Circuit
A-B Not Used A-B Not Used
Trailer Relay Output-N.O. Trailer Relay Output-N.O.

C YEL 318 Contact-Left Rear Stop/ C YEL 318 Contact-Left Rear Stop/
Turn Lamp Turn Lamp
Trailer Stop Lamp Trailer Stop Lamp ____
D RED 950 D RED 1411
Relay-N.O. Contact Relay-N.O. Contact
Trailer Relay Output-N.O. Trailer Relay Output-N.O.
DKGRN 319 Contact-Right Rear DKGRN 319 Contact-Right Rear
BRN Park Lamp Feed BRN Park Lamp Feed

G Not Used G Not Used
1998 -
MD-lsuzu
/-nj'""1!^
y
5 6 7
[Z][6][5] 11
8 9 10
[nl@[9][8]
I:
@ @EI 3
12 13 14
@^@ra 15 16 17 18
>
-LILT
^
339156
12162871 14 Way M
Information ASM 14F SLD (GRY) Information (GRY)
Circuit Circuit
5-6
Not Used 5-6
Not Used
7 ORN 24 Back Up Lamp Feed 7 ORN 7 Back Up Lamp Feed
8-10
Not Used 8-10
Not Used
12-14
Not Used 12-14
Not Used

15 LT GRN/BLK 822 15 LT GRN/BLK 24
Sensor Signal Sensor Signal
18
Not Used 18
Not Used
C408
n n n
/
^ un u \
"S
<t''% \ [ A 0 B
)
]
ss-^
y' \
n
i[ n
277418

15300027 15300002
Information
2 Way F Metri-Pack Information
2 Way M Metri-Pack
280 Series, Sealed(BLK) 280 Series, Sealed(BLK)
Circuit Circuit
A BRN 341 Fuse Output-Ignition A BRN 341 Fuse Output-Ignition
B BLK 150 Ground B BLK 150 Ground
1998 -
MD-lsuzu
C410
^J=DO ^ |T 1
/
/- ~"~""'
' '
^
/yt
ji na a' P
//I=---
a
n[
^
\^^
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62447

12124107

12052848
Connector Part Connecto r Part 6 Way M Metri-Pack
Information
6 Way F Metri-Pac k Informs tion 150 Series, Sealed,
Self-locking (BLK)
Circuit Circuit
A PPL 30 Fuel Gauge Sensor Signal A PPL 30 Fuel Gauge Sensor Signal
B BRN 341 Fuse Output-Ignition B BRN 139 Fuse Output-Ignition
C BLK 350 Ground C BLK 350 Ground
D
Not Used D
Not Used
E QRA 120 Fuel Pump Motor Feed E
Not Used
F
Not Used F
Not Used
<^" "^
1
1
^-
nM
D:
EEl
ES]
to f|
C 1B
Q
UaJ
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A
G
B
'
C ')lf
D
J
Y.
^^ U)
222652
12047937 12047931
ASM 8F Metri-Pack
ASM 8M Metri-Pack
150 (Black) 150 Series (Black)
Circuit Circuit
A
Not Used A
Not Used
B PNK 139 Fuse Output Ignition B BRN 441 Fuse Output Ignition
C LTGRN 24 Back Up Lamp Feed C LTGRN 24 Back Up Lamp Feed
Ignition Switch Output
D YEL D PPL 806 Fuse Output Crank
Crank
1998 -
MD-lsuzu

12047937 12047931

ASM 8P Metri-Pack ASM 8M Metri-Pack
150 (Black) 150 Series (Black)
Circuit Circuit
Transmission Mounted Transmission Mounted
E ORN/BLK 434 Neutral Safety Switch E ORN/BLK 434 Neutral Safety Switch
Signal Signal
F
LT GRN/BLK 822 F LT GRN/BLK 822
Return Signal

G PPL/WHT 821 G PPL/WHT 821
Signal Signal
H
Not Used H
Not Used
C413
73184,
12162102
12162144
Connector Part Connector Part 4 Way M Metri-Pack
Information
4 Way F Metri-Pack Information 150 Series, Sealed,
Self-Locking (BLK)
Circuit Circuit
A
Wheel Speed Sensor A
Wheel Speed Sensor
BRN 882 BRN 882
Signal-Right Rear Signal-Right Rear
Wheel Speed Sensor Wheel Speed Sensor

B WHT 883 B WHT 883
Return-Right Rear Return-Right Rear
C BLK 884 C BLK 884
Signal-Left Rear Signal-Left Rear

D RED 885 D RED 885
Return-Left Rear Return-Left Rear
1998 -
MD-lsuzu
JTUL
v
BSQ EBB
^ 229954
Connector Part 12162918 Connector Part

2 Way M
Information 2 Way F (GRY) Information (GRY)

Circuit Circuit
1 RED 6 Starter Solenoid Feed 1 RED 2 Starter Solenoid Peed
2 RED 2 Fuse Output Battery 2 RED 1 Starter Solenoid Feed
C420
A B
40381
12052644 12162343
2 Way F Metri-Pack 2 Way M Metri-Pack
150 Series, Sealed (LT GRA) 150 Series, Sealed (LT GRA)
Circuit Circuit
A BRN 323 Shift Solenoid Feed A BRN 323 Shift Solenoid Feed
BLK 150 Ground BLK 150 Ground
1998 -
MD-lsuzu
n 1
y
/^ ~\ L: \
A B C D D C B A
E F G H H G F E
\ -^ Ys^.
/
^
339146
8 Way F 8 Way M


Circuit Circuit
A BRN 88 Side Marker Lamp A BRN 20 Side Marker Lamp
B
Not Used B
Not Used
C ORN
Power Window C ORN
Power Window
443 7
Relay Output Relay Output
D BLK 68 Ground D BLK 4 Ground
E ORN 342 Heated Mirror E ORN 32 Heated Mirror
LT LT
F 445 Power Window Lock F 8 Power Window Lock
GRN/WHT GRN/WHT
LT LT
G 446 Power Window Up G 9 Power Window Up
GRN/RED GRN/RED
H LT GRN/BLK 447 Power Window Down H LT GRN/BLK 10 Power Window Down
n n
r
A B
) ( B A )
^
339136
Connector Part
2 Way F Connecto Partr
2 Way M
Information (GRY) Informa tion (GRY)
Circuit Circuit
A ORN 1 Mirror Lamp Feed A ORN 32 Mirror Lamp Feed
B BLK 2 Mirror Lamp Ground B BLK 33 Mirror Lamp Ground
1998 -
MD-ISUZU
n
/
/^
A B C D
n D C B A
\
E F G H H G F E
\ / '<
)
^
339146
8 Way F 8 Way M
Connector Part
Connector Part

Information (BRN) Information (BRN)

Circuit Circuit
A BRN 89 Side Marker Lamp A BRN 20 Side Marker Lamp
B
Not Used B
Not Used
C Power Window C ORN 3 Power Window

CRN 441
Relay Output Relay Output
D BLK 69 Side Marker Lamp D BLK 4 Side Marker Lamp
E ORN 343 Heated Mirror E ORN 32 Heated Mirror
LT LT
F 445 Power Window Lock F 8 Power Window Lock
GRN/WHT GRN/WHT
LT LT
G 446 Power Window Up G 9 Power Window Up
GRN/RED GRN/RED
H LT GRN/BLK 447 Power Window Down H LT GRN/BLK 10 Power Window Down
n n
A B (^ B A )
^
339136
2 Way F Part 2 Way M

Connector Part

Connecto r
Information (GRY) Informs tion (GRY)
Circuit Circuit
A ORN 1 Mirror Lamp Feed A ORN 32 Mirror Lamp Feed
B BLK 2 Mirror Lamp Ground B BLK 33 Mirror Lamp Ground
1998 -
MD-lsuzu
C703
^ & m
n
^ ftSEQ
a
95864
120409 77 15300003
3 Way F Metri-Pack 280 3 Way M Metri-Pack 280
Series, Sealed (BLK) Series,Seialed (BLK)
Circuit Circuit
A BRN 241 Fuse Output-Ignition A BRN 241 Fuse Output-Ignition
Two Speed Rear Axle Shift Two Speed Rear Axle Shift
B GRA/BLK 1467 B GRA/BLK ,.
Motor Relay Output-Coil Motor Relay Output-Coil
C BLK 450 Ground C BLK 450 Ground
Harness Routing Views Turn Signal Harness, Right Side
Turn Signal Harness, Left Side
216305
216301
1998 -
MD-lsuzu
Accessories_________________________Wiring
Front Chassis Harness (ABS-Hydraulic)
216309
1998 -
MD-ISUZU
Front Chassis Harness RPO-JE4
216343
7995 -
MD-lsuzu
Front Chassis Harness to Brake Components (ABS-Hydraulic)
216346
1998 -
MD-ISUZU
Front Chassis Harness to Brake Components
216350
Front Chassis Harness to Brake Components

(ABS-Hydraulic)
216352
1998 -
MD-lsuzu
Front Chassis Harness, Center
1998 -
MD-lsuzu
Front Chassis Harness at Rear of Engine Front Chassis Harness to Cab
216371 216374
Cover to Cab Interface Removal Front Chassis to Harness Rear Support
216373 216375
7998 -
MD-ISUZU
Front Chassis Harness, Maxi-Fuse Block
216377
Front Chassis Harness to Control Valves
223179
1998 -
MD-lsuzu
Front Chassis Harness to Coolant Level

Switch RPO-LXO
216381
Trailer Stop and ABS Relay Installation to Bracket RPO-JE3
^1
223279
1998 -
MD-lsuzu
>dy and Accessories Wiring Systems 8-267
Trailer Stop and ABS Relay Installation to Bracket RPO-JE4
223187
ront Chassis Harness to ABS Control Unit

RPO-JE4 and JE5
216384
8 -
MD-lsuzu
Front Chassis Harness to Engine
223194
1998 -
MD-lsuzu
Front Chassis Harness to Starter Harness
223206
1998 -
MO-lsuzu
8-270 Wiring and Accessories
Systems_________________________Body
Front Chassis Harness to Starter Harness RPO-M54 and JE3
223210
1998 -
MD-lsuzu
Front Chassis Harness to Left Side of Engine
223214
Front Chassis Harness to Left Rear of

Frame RPO-JE3
216389
1998 -
MD-lsuzu
Front Chassis Harness to Left Rear of Frame RPO-JE4 and JE5
223217
Front Chassis Harness to Exhaust Brake
216401
1998 -
MD-lsuzu
jdy and Accessories Wiring Systems 8-273
Front Chassis Harness to Right Rear of Frame
223222
Front Chassis Harness to Low Air

Pressure Switch
216402
18 -
MD-lsuzu
Transmission Harness to Automatic Transmission (Backup Switch and Speed Sensor)
216412
1998 -
MD-ISUZU
Transmission Harness to Manual Electric Brake Control Harness, Center

Transmission RPO-MTH/MUT/MWK
(Backup Switch and Speed Sensor)
216426
Fuel Tank Harness, Left Side

216421
216429
1998 -
MD-lsuzu
Systems_________________________Body
Fuel Tank Harness to Level Controls (1 of 2)
216454
1998 -
MD-ISUZU
Fuel Tank Harness to Level Controls (2 of 2) Electric Brake Control Harness, Center
RPO-JE3 and EM2
216463
Fuel Tank Harness, Right Side 216483
Electric Brake Control Harness, Center

RPO-JE3 and FPL
216465
216486
1998 -
MD-ISUZU
Electric Brake Control Harness, Center Electric Brake Control Harness, Center
RPO-JE3 and EQ8 RPO-JE3 and ESS
216491 216494
1998 -
MD-lsuzu
Accessories_________________________Wiring
Electric Brake Control Harness, Rear RPO-JE4 and JE5 and G40
216499
1998 -
MD-ISUZU
Systems_________________________Body
Electric Brake Control Harness, Rear (ABS-Air)
216501
1998 -
MD-lsuzu
>dy and Accessories Wiring Systems 8-281
Trailer Harness, Front
216502
Trailer Harness, Center
216503
8 -
MD-lsuzu
Trailer Harness, Center RPO-FQT and U86
216093
Tail Light Harness
202612
1998 -
MD-lsuzu
Body and Accessories Instrument Panel, Gauges and Console 8-283
Instrument Panel, Gauges and Console

Specifications

Specification
Multifunctional Alarm Module Mounting Bolt 3N.m 27 to in
Instrument Cluster Schematic References

Subsection Name
Instrument Panel Dimming Cell 117 8Lighting Systems
Instrument Cluster Schematic Icons

AA 19384
1998 -
MD-lsuzu
8-284 Instrument Panel, Gauges and Console Body and Accessories
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998 -
MD-lsuzu
1998 -
MD-lsuzu
:86 Instrument Panel, Gauges and Console Body and Accessories
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MD-lsuzu
'
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998 -
MO-lsuzu
dy and Accessories Instrument Panel, Gauges and Console 8-289
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7995 -
MD-lsuzu
Component Locator
Instrument Cluster Components

Engine Coolant
On the left side of the IP, part of the Instrument Cluster Instrument Cluster
Temperature
instrument panel cluster (IPC) Component Views Connector End Views
(ECT) Gauge
Engine Coolant
Instrument Cluster Instrument Cluster
Temperature (ECT) On the upper left side of the engine
Gauge Sensor
Engine Oil Pressure On the left side of the IP, part of the Instrument Cluster Instrument Cluster
(EOP) Gauge instrument panel cluster (IPC) Component Views Connector End Views
Engine Oil Pressure Instrument Cluster Instrument Cluster
On the right side of the engine block
(EOP) Gauge Sensor Component Views Connector End Views
Engine Oil Pressure On the inside left frame rail, in the front of Instrument Cluster Instrument Cluster
(EOP) Indicator Switch the oil filter Component Views Connector End Views
Fuel Gauge
Fuel Sender, Left On the outboard of the left frame rail in the Instrument Cluster Instrument Cluster
Side Tank fuel tank Component Views Connector End Views
Fuel Sender, Right On the outboard of the hght frame rail in Instrument Cluster Instrument Cluster
Side Tank the fuel tank Component Views Connector End Views
Under the left side of the IP, near the data
Hourmeter
link connector (DLC)
Indicator Lamps Check On the left side of the IP, part of the Instrument Cluster Instrument Cluster
Switch instrument panel cluster (IPC) Component Views Connector End Views
Instrument Panel Instrument Cluster Instrument Cluster
On the left side of the IP
Cluster (I PC) Component Views Connector End Views
Instrument Panel Cluster On the upper IP harness to the instrument Instrument Cluster Instrument Cluster
(IPC) C1 (15 Cavities) panel cluster (IPC) Component Views Connector End Views
Low Engine Coolant On the lower IP harness, part of diode

Level Indicator Lamp module 1, plugged into joint connector 1,
Diode (D200) terminals A1, B1 and C1

Low Engine Coolant On the left cab bridge, on the bottom of Instrument Cluster Instrument Cluster
Level Indicator Switch the radiator surge tank Component Views Connector End Views
Park Brake Switch Instrument Cluster Instrument Cluster

In the center of the IP, below the radio
(ABS Air) Component Views Connector End Views
Park Brake Switch Instrument Cluster Instrument Cluster
On the park brake lever bracket
(Hydraulic Brakes) Component Views Connector End Views
Speedo Adapter (Vehicle

Speed Sensor [VSS] Under the right seat
Buffer) (Diesel)
Speedometer
Tachometer
1998 -
MD-lsuzu
Instrument Cluster Components (cont'd)

Vehicle Speed Sensor
(VSS) (Automatic On the transmission rear tailshaft housing
Transmission)
Vehicle Speed Sensor

(VSS) (Manual On the transmission rear tailshaft housing
Transmission)
Vehicle Speed Sensor Instrument Cluster Instrument Cluster
(VSS) Buffer Component Views Connector End Views
Voltmeter
Instrument Cluster Component Views

Instrument Panel and Instrument Cluster With Gauges
228466
Legend
(1) Speedometer (5) Engine Oil Pressure Gauge
(2) Tachometer (6) Voltmeter
(3) Air Pressure Gauge (7) Engine Coolant Temperature (ECT) Gauge
(4) Fuel Gauge (8) Indicator Lamps Check Switch
1998 -
MD-lsuzu
Engine Harness to Engine, Upper LH Front View
228789
Legend
(1) Glow Plug (2) Engine Harness to Front Chassis
Connector C118 (2 cavities)
1998 -
MD-lsuzu
228805
Legend
7995 -
MD-lsuzu
Front Chassis Harness to Engine, LH Front View
228801
Legend
(1) Engine Harness (3) Engine Oil Pressure Indicator Switch
(2) Engine Oil Pressure Indicator Switch (4) Front Chassis Harness
Connector
1998 -
MD-lsuzu
Fuel Tank Harness, LH Side
23)729
Legend
(1) Fuel Sender (2) Fuel Tank
7998 -
MD-lsuzu
Front Chassis Harness to Radiator Surge Tank, Forward View
231750
Legend
(1) Radiator Surge Tank (3) Front Chassis Harness
(2) Cab Bridge (4) Low Engine Coolant Level Indicator Switch
1998 -
MD-lsuzu
231675
Legend
(4) Cigar Lighter
1998 -
MD-lsuzu
Park Brake
231691
Legend
(1) Park Brake Lever (2) Park Brake Switch (Hydraulic Brakes)
1999 -
MD-lsuzu
228786
Legend
(1) Lower IP Harness (7) Pre Stroke Power Cut Relay Fusible
(2) Inverting Driver Module Connector Link, 30 A
(ABS-Hydraulic) (8) Engine Control Module
(3) Inverting Driver Module (ABS-Hydraulic) (9) Engine Control Module Connector C2
(4) Multifunction Alarm Module (80 cavities)
(5) Ignition Main Relay (10) Engine Control Module Connector C1
(40 cavities)
(6) Speedo Adapter (Vehicle Speed Sensor
(VSS) Buffer)
1998 -
MD-lsuzu
Automatic Transmission Harness, Upper Left Rear View
228797
Legend
(1) Backup Lamps Switch (3) Neutral Switch
(2) Vehicle Speed Sensor (VSS) (4) Front Chassis Harness
1998 -
MD-lsuzu
Starter Harness to Manual Transmission, Upper Right Forward View
228793
Legend
(1) Backup Lamps Switch (2) Vehicle Speed Sensor
1998
MD-lsuzu
Visual Identification Engine Oil Pressure Gauge Sender (Isuzu)
Instrument Cluster Connector End Views
Air Suspension Dump Switch
r n
2
l^l 6 1
r
4 3 5
246685
1 Way
Connector Part
Information
Female
231646
Circuit
6 Way
Connector Part

Oil Pressure Switch

Information
Female A BRN/WHT
Signal
Circuit
Pin Wire Color No. Function Fuel Sender (Single Fuel Tank)
1 PNK 121 Fuse Output-Ignition
Air Suspension Dump
2 BLU 122
Valve Solenoid Feed
Not Used
|
3-4
5 BRN 123 Illumination |

Interior lamp
(;? ^)
6 BLK/RED 124
Dimming Buss
D C B A
Engine Coolant Temperature Gauge Sensor
38608
12162189
Connector Part 4 Way F Metri-Pack
Information 150.2 Series Pull To Seat,
A Sealed (BLK)
Circuit
A BLK 350 Ground
B-C
Not Used
35437
Fuel Gauge Sensor
D PPL 30
12052644 Signal
Connector Part
2 Way F Metri-Pack
Information
150 Series (GRY)
Circuit
Multifunction Alarm
A GRN 11 Module-Water Temp.
(Engine Shutdown)
B Not Used
7998 -
MD-lsuzu
Fuel Sender (Dual Fuel Tank-Left Hand) Fuel Sender and Transfer Pump
Control Module
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38608
121 621 89
12162189 73212
Conn ector
Connector Parrt
Part 4 Way F Metri-Pack 12059573
120)59573
4%

/ay FMe tri-Pack
Conn ector Part
Connector
Info
Information
rmation 150 Series Pull To Seat,
.2SSeries
150.2
6V
6 Way
Vay F Metri-Pack
Info
Information
rmation
led (BLK
Sealed
Sea (BLK)) 280) Series, Sealed (BLK)
280
Circuit Circuit
Pin Wire Cc
Color
)lor No. F
Function
unction Pin Wire Color Function
No.
A BLK 350 Gro)und
Ground A PNK 139 Fuse Output-Ignition
B-C Usedj
Not Used Fuel Gauge Sensor
B LT BLU 1937
Fuel;l Gau Signal-Right
Fue ge Sensor
Gauge
D DK BL
BLUU 1936
Signal-Left
Sig nal-Le ft Fuel Gauge Sensor
C DK BLU 1936
____ Signal-Left
Fuel Sender (Dual Fuel Ta nk-R ight Hand)
Tank-Right Fuel Pump Relay
D LTGRN 497
Output-Coil-Secondary
E BLK 350 Ground
Fuel Gauge Sensor
| F PPL 30
Signal
I |
Fuel Transfer Pump
(;? % I
D C B A
38608

12162189
Metri-Pack
[ .1
Information 150.2 Series Pull To Seat,
B A
Sealed (BLK)
Circuit
'mj'
\^"V^/
Pin Wire Color No. Function 258174
A BLK 350 Ground 12010973
Connector Part
B-C
Not Used 2Way M Weather
Information
Fuel Gauge Sensor Pack (BLK)
D DKBL u 1937
Signal-Right Circuit
A BLK 350 Ground
B GRA 120 Fuel Pump,Motor Feed
1998 -
MD-lsuzu
Fuel Transfer Pump Relay Engine Coolant Temperatu re Gauge

Connector (Isuzu)
^^^
1flnn@| ff
..1-1..U,.
1lyDD"!J
W\11,85,1 >
39670
12129716 246685
Conn ector Par1 4 Way F Mletri-Pack 1 Way

Connector Part
Info rmation 280 Series Flexlock,
, Information
Female
Sealed (GFFlY)
Circuit
Circuit Pin Wire Color No. Function
Pin Wire Color No. Function Engine Coolant
30 PNK 139 Fuse Output-Ignition A GRN 4 Temper ature Gauge
85 PNK 139 Fuse Output-Ignition Sender
Fuel Pump Relay

86 LT GRN .- Hourmeter
Output-Coil-Secondary
87 GRA 120 Fuel Pump Motor Feed
11
/^ "\
A B C D
222755
Connector Part 12045813

Information ASM 4F M/P 150 (NAT)
Circuit
A YEL 37 Generator
B
Not Used
C BLK 330 Ground
D
Not Used
1998 -
MD-lsuzu
IP Harness Connector C1 (15 Way) IP Harness Connector C2 (9 Way)
ff5B
d] [I] BE1!!] d] E
|Czl B Oltyd] CD
|64l@3|gI|(H)gO][9](8] d] (3 HI (5]
j V J
\^
236545 236605
15 Way 9 Way F
Connector Part

Connector Part

Information
Female Information (BLK)
Circuit Circuit
Generator 1 BRN 8 Charge Indicator Lamp
1 BRN 6
Indicator Lam P 2
Not Used
Exhaust Brake Right Turn Signal
2 BLK/WHT 90 3 LT BLU 17
Indicator Lamp
Indicator Lamp
Exhaust Brake
3 BLK 91 Aux Brake
Indicator Lamp 4 YEL/BLK 10
Indicator Lamp
Do Not Shift
4 GRY 7 Low Coolant
Indicator Lamp 5 YEL/RED 15
Indicator Lamp
Park Brake
5 BLU 12 6 BRN 28 Tachometer Ignition
Indicator Lamp
7
Not Used
6 BRN 1 Fused Output Ignition
Check Gauges
Daytime Running Lights 8 BLU/YEL 19
7 BRN 58 Indicator Lamp
Indicator Lamp
Primary Brake
8 LTGRN 38 ABS Indicator Lamp 9 BRN/WHT 9
Indicator Lamp
9 BLK 4 Ground
Service Engine Soon
10 BRN/WHT 36
Indicator Lamp
11
Service Parking Brake
BLK/WHT 13
Indicator Lamp
Apply Parking Brake

12 LTGRN 11
Indicator Lamp
Left Turn Signal
13 BLU 18
Indicator Lamp
High Beam
14 RED/YEL 14
Indicator Lamp
BLU
Daytime Running Lights
15 59
Indicator Lamp
1998 -
MD-lsuzu
IP Connector C3 (17 Way) IP Harness Connector C4 (7 Way)
[8] S [6] CEtjB 03]^ E

|17)(16)|15|(14]@3|[12][H]|10)[9]
\>- ^
236600 236724
17 Way 7 Way
Connector Part

Connector Part
Information
Female Information
Female
Circuit Circuit
1 BRN 2 Illumination BRN 70 Fused Output Ignition
2 BLK/RED 3 Rheostat Differential Lock
PPL 63
3 BRN 33 Check Gauge Logic (6H) Panel Lamp
BLK 69 Ground Bus
4 BRN/BLK 34 Check Gauge Logic (6H)
4-7 Not Used
Check Gauge
5 BLU/YEL 20
Logic (Gas)
IP Harness Connector C5 (13 Way)
6 BLK 31 Tachometer (Ground)
7-9
Not Used
10 PPL 24 Fuel Gauge Input
11 BRN/WHT 211 Oil Pressure Gauge
12 BRN 21 Fused Input Ignition [l][I][I]t11^

13 BLK 27 Voltmeter (-)
14
15
BRN
BLK
26
22
Voltmeter (+)
Meter Ground
Baa iw) [11][12][13
16 GRN 23 Water Temperature

17 WHT 30 Tachometer Signal
235963
Connector Part
13 Way F
Information (GRN)
Circuit
1-6 Not Used
Air Suspension Dump

BLU 65
Switch
Air Suspension Dump
BLK 68
Switch
9-13 Not Used
1998 -
MO-ISUZU
Low Air Pressure Switch Park Brake Switch, D<a\/time Running Lamps
(Air Eir akes)
i
^^^^^^^~^^
|
^\
< '=Sy B
i
A
'w\st
lliIJ
-^^
236406

12065400 246698
Connector Part 2 M
2 Way F Metri-Pack Connector Part
Way
Information
150 Series, Sealed (GRN) Information (GRY)
Circuitt Circuit
Brake Warning Indicator Daytime Running
A TAN/WHT 33
Lamp Output A LT BLU 74 4 Lamps (DRL) Off Relay
B BLK 150 Air Brake
Ground
Park Brake Switch
B BLK 746
Low Coolant Level Indicator Switch Air Brake
Speedometer
ET"L
itg^ BL 3"
|C] d3(D
^^^^^^^^^^^^^^^^^^
236598
Connector Part

12052641
236599
Information
ASM 2F M/P 150 (BLK)
5 Way
Connector Part

Circuit
Pin Wire Color Information
Male
No. Function
Low Coolant Sensor Circuit
A LT GRN 1478 Pin
Signal Wire Color No. Function
B BLK 150 Ground Interior Lamp

A BLK/RED 4C)
Dimming Buss
B BRN 41 Ignition
C BRN 44 Illumination
D WHT 42 Speed Signal
E BLK 43 Ground
1998 -
MD-lsuzu
Body and Accessories instrument Panel, Gauges and Console 8-309
Vehicle Speed Sensor Vehicle Speed Sensor (Manual)
A B C
A B
40389
35437 3 Way F
Connector Part

Connector Part

12052644 Information (GRN)
Information
ASM 2F M/P 150 (LT GRY) Circuit
Circuit Pin Wire Color No. Function
Pin Wire Color No. Function Vehicle Speed Sensor
A LT GRN/BLK 24
Vehicle Speed Sensor Signal
A PPL/WHT 821
Signal Vehicle Speed Sensor
B PPL/WHT 25
Vehicle Speed Sensor Return
B LT GRN/BLK 822
Return C PNK 26 Fuse Output-Ignition
Gauge -
Engine Coolant Temp Always Cold
Operate the engine and compare the actual engine coolant
temperature with the temperature indicated by the
instrument cluster temperature gauge.
1 -1-C (30-F)
Is the deviation between the actual engine coolant
temperature and the indicated coolant temperature within
the specified value? Go to Step 2 Go to Step 3
This indicates that the temperature gauge is functioning
properly. Check the engine cooling system operation if
2
appropriate.
Has the condition been resolved? System OK
1. Disconnect the connector at the engine coolant

temperature sensor.
3 a fused jumper wire between terminal A
3. Connect

(Diesel) or C (Gas) of the engine coolant

temperature sensor connector and ground.
Does the temperature gauge indicate hot? Go to Step 6 Go to Step 4
1998 -
MD-lsuzu
Gauge -
Engine Coolant Temp Always Cold (cont'd)
1. Disconnect the connector at the instrument cluster.

2. Connect a self-powered test lamp between terminal
C16 of the instrument cluster connector and terminal
4 A (Diesel) or C (Gas) of the engine coolant
temperature sensor connector for CKT 4 or CKT 135

(DK GRN), CKT 385 or CKT 23 (GRN).
Repair the open in CKT 4 or CKT 135 (DK GRN),
CKT 385 or CKT 23 (GRN) between the engine coolant
5
temperature gauge sensor and the instrument cluster.

Replace the engine coolant temperature sensor. Refer to
6 Engine Coolant Temperature Sensor Replacement.

Replace the instrument cluster. Refer to IP Cluster
7 Replacement (Instrument Cluster).
Gauge -
Eng Coolant Temp Inaccurate or Inoperative
Operate the engine and compare the actual engine coolant
temperature with the temperature indicated by the
instrument cluster temperature gauge.
1 -1'C (30-F)
Is the deviation between the engine coolant temperature
and the indicated coolant temperature within the
Check the operation of the cooling system.
2
Is the cooling system operating properly? System OK

1. Disconnect the connector at the engine coolant
temperature gauge sensor.
2. Connect one red lead of a J 33431-B at engine
coolant temperature gauge sensor connector
terminal A for CKT 4 and CKT 135 (DK GRN), and
CKT 385 and CKT 23 (GRN).
3. Connect the other lead to ground.
38-C (100-F)
3
4. Adjust the tester to 1,305 ohms and observe the
126-C (260-F)
temperature gauge reading.
5. Adjust the tester to 49.5 ohms and observe the
temperature gauge reading.
Go to Engine
6. The temperature gauge should indicate approximately Coolant
38'C(100'F), then approximately 100'C(260'F). Temperature
Does the temperature gauge indicate the specified cold Sensor
and then hot values? Replacement. Go to Step 4
Check the temperature gauge. Go to IP Cluster
4 Did the temperature gauge indicate a value significantly Replacement
126-C (260-F)
below the specified value for hot at 49.5 Q? (Instrument
Go to Step 5 Cluster).
1998 -
MD-lsuzu
Gauge -
Eng Coolant Temp Inaccurate or Inoperative (cont'd)
1. Disconnect the 17 way IP harness connector at the
instrument cluster.
2. Connect an ohmmeter between instrument cluster

connector terminal C16 and terminal A (Diesel) or C
(Gas) of the engine coolant temperature gauge
5 20 Si
sensor connector terminal A for CKT 4 and CKT 135
(DK GRN), and CKT 385 and CKT 23 (GRN). Go to IP Cluster
Are the wire resistances of CKT 4 and CKT 135 Replacement
(DK GRN), and CKT 385 and CKT 23 (GRN) above the (Instrument
specified value? Go to Step 6 Cluster).
1. Locate the high resistance in CKT 4 and CKT 135

(DK GRN), and CKT 385 and CKT 23 (GRN)
between the instrument cluster and the engine
6
coolant temperature gauge sensor.
2. Repair the high resistance.

Gauge -
Engine Oil Pressure Always High
1. Check the actual engine oil pressure with the engine

running.
2. Compare this value to the indicated value.
1 3. The oil pressure gauge should indicate approximately 69kPa (10 psi)
the same as the actual pressure, within the
specified range.
Does the oil pressure gauge indicate a reading close to
the specified value? Go to Step 2 Go to Step 3
Inspect the engine for operating problems.
2
Is the engine operating properly? System OK
1. Disconnect the connector at the engine oil pressure

indicator sender.
2. Connect a fused jumper wire between the oil

pressure indicator sender connector terminal A for
3
CKT 7 (BRN/WHT) and ground.

3. The oil pressure gauge should indicate 0 kPa (0 psi)
or less.
Does the oil pressure indicate low pressure? Go to Step 4 Go to Step 5
Replace the engine oil pressure sender.
4

instrument cluster.
5 2. Connect a self-powered test lamp from the
instrument cluster connector C11 to the engine oil

pressure indicator sender terminal A.
1998 -
MD-lsuzu
Gauge -
Engine Oil Pressure Always High (cont'd)
Replace the instrument cluster.
6

Locate and repair the open in one or more of the following
circuits between the instrument cluster and the engine oil
pressure indicator sender:
1. CKT7 (BRN/WHT)
7
CKT 383 (BRN/WHT)

2.
3. CKT 211 (BRN)

4. CKT 331 (TAN/WHT)
Gauge -
Engine Oil Pressure Always Low
1. Check the actual engine oil pressure while the
engine is running.
1 Compare the actual engine oil pressure to the

2.
69kPa (10psi)
indicated value.
Is the oil pressure indicated by the gauge approximately
equal to the actual oil pressure within the specified range? Go to Step 2 Go to Step 3
2

indicator sender.
3. Connect one red lead of a J 33431-B at terminal A

of the engine oil pressure sensor connector for
3 CKT 211 (BRN), CKT 7 or CKT 383 (BRN/WHT) or 550 kPa (80 psi)
CKT 331 (TAN/WHT).

5. Adjust the tester to 88 ohms.
Is the test oil pressure gauge reading higher than the
1. Disconnect the 17 way IP harness connector.

instrument cluster connector terminal C12 and the
4 engine oil pressure indicator sender connector Go to IP Cluster

terminal A for CKT 211 or CKT 383 (BRN) or Replacement

CKT 331 (TAN/WHT). (Instrument
Does the test lamp light? Go to Step 5 Cluster).
Locate and repair CKT 211
the short to ground in for
(BRN), CKT 383 or CKT 7 (BRN/WHT), or CKT 331
5 (TAN/WHT) between the instrument cluster and the engine
oil pressure indicator sender.

Replace the engine oil pressure indicator sender.
6
1998 -
MD-lsuzu
Gauge -
Eng Oil Pressure Inaccurate or Inoperative
1. Check the actual engine oil pressure while the

engine is running.
1
2. Compare this value to the indicated value. 70kPa (10 psi)
Does the oil pressure gauge reading meet the

2

indicator switch.

3. Connect one red lead of a J 33431-B at terminal A
of the engine oil pressure switch connector.
0 kPa (0 psi)
3 4. Connect the other lead to ground.
88 kPa (550 psi)
5. Adjust the tester to 0 ohm. The test oil pressure
gauge should indicate 0 kPa (0 psi).
6. Adjust the tester to 88 Sl. The test oil pressure
gauge should indicate 550 kPa (80 psi). Go to Engine Oil
Does the test oil pressure gauge indicate the correct Pressure Switch
values? Replacement Go to Step 4

instrument cluster.
2. Connect a fused jumper wire between the B+ and

terminal C12 of the instrument cluster connector.
3. Connect a fused jumper wire between terminal C15

of the instrument cluster connector for CKT 22 (BLK)
and ground. 0 kPa (0 psi)
4
4. Connect one red lead of a J 33431-B at terminal C11 88 kPa (550 psi)
of the instrument cluster connector.

6. Adjust the tester to 0 ohm. The oil pressure gauge Go to IP Cluster
should indicate 0 kPa (0 psi).
Replacement
7. Adjust the tester to 88 ohms. (Instrument
Does the oil pressure meet the specified value? Go to Step 5 Cluster)
1. Locate the high resistance in CKT 7, CKT 211 or

CKT 383 (BRN/WHT) or CKT 331 (TAN/WHT).
5
2. Repair the high resistance.

Gauge -
Fuel Always Indicates Empty (Single Tank)
Check condition of ignition switch circuit breaker.
1
Is circuit breaker OPEN? Go to step 2. Go to step 3.
Locate and repair cause of the overload.

2
Is the repair complete? Go to step 6.
1. Disconnect fuel sender or fuel sender and fuel pump

connector.
3

Does the fuel gauge indicate full? Go to step 4. Go to step 5.
1998 -
MD-lsuzu
Gauge -
Fuel Always Indicates Empty (Single Tank) (cont'd)
Replace the fuel sender or fuel sender and fuel pump.
4 Refer to Fuel Pump Replacement.

Locate and repair short to ground CKT 30 (PPL) wire
in
between IP cluster and fuel sender or fuel sender and

5
fuel pump.
Is the repair complete? System OK Go to step 7.
Replace the circuit breaker.

6

Replace the fuel gauge. Refer to IP Cluster Replacement
7 (Instrument Cluster).
Gauge -
Fuel Always Indicates Empty (Dual Tanks)

DEFINITION: Fuel gauge indicates empty when there is fuel in tank (Dual tanks).
1. Remove connector at fuel sender and balance pump

control module.
1
2. Place the ignition switch in RUN.

Does the fuel gauge indicate FULL? Go to step 5. Go to step 2.
Check for a short to ground in CKT30 (PPL) between the
fuel sender and balance pump control module connector
2
and the IP cluster harness connector.

Was a short to ground found? Go to step 3. Go to step 4.
Repair the short to ground in CKT30 (PPL) between the
fuel sender and balance pump control module and the IP
3
harness connector.


1. Connect jumper between terminal C and terminal F
a
at the fuel sender and balance pump control module

harness connector.
5 2. Visually inspect the fuel level in the LH fuel tank.
3. Check the fuel gauge.

Does the fuel gauge indicate the approximate fuel level of
the LH fuel tank? Go to step 9. Go to step 6.
Check for short to ground
a CKT1936 (DK BLU)
in
between the fuel sender and balance pump control module
6
harness connector and the LH fuel tank harness connector.

Was a short found? Go to step 7. Go to step 8.

Repair the short in CKT1936 (DK BLU) between the
fuel sender and balance pump control module and the
7
LH fuel tank.


Replace the fuel sender and fuel pump assembly. Refer to
8 Fuel Pump Replacement.
1998 -
MD-lsuzu
Gauge -
Fuel Always Indicates Empty (Dual Tanks) (cont'd)
1. Connect a jumper wire between terminal B and
terminal F at the fuel sender and balance pump
control module.
9
2. Visually inspect the fuelfuel sender and flevel in the
RH fuel tank.
3. Check the fuel gauge.

Does the fuel gauge indicate the approximate fuel level of
the RH fuel tank? Go to step 10. Go to step 11.
Replace the fuel sender and balance pump control module.
10 Refer to Fuel Pump Replacement.

Check CKT1937 (LT BLU) for an open condition between
the fuel sender and balance pump control module harness
11
connector and the RH fuel tank harness connector.

Was an open condition found? Go to step 12. Go to step 13.
Repair the open in CKT1937 (LT BLU) beetween the fuel
sender and balance pump control module harness
12
connector and the RH fuel tank harness connector.


Gauge -
Fuel Always Indicates Full (Single Tank)
1. Disconnect fuel sender or fuel sender and fuel pump
harness connector at the fuel tank.
1
2. Connect a fused jumper from CKT30 (PPL) at the
fuel tank connector to chassis ground.
3.Place the ignition switch in RUN.

Does the fuel gauge indicate FULL? Go to Step 2 Go to Step 5
Check for open in CKT30 (PPL) between the fuel sender
2 and the IP harness connector.
Was an open wire found? Go to Step 3 Go to Step 4
Repair the open in CKT30 (PPL) between the fuel sender

3 and the IP harness connector.

Connect fused jumper between the CKT30 (PPL) and

a
the CKT350 (BLK) at the fuel sender or fuel sender and

5
fuel pump connector.
Does the fuel gauge indicate FULL? Go to Step 6 Go to Step 7

Locate and repair the open in CKT350 (BLK) between the
fuel sender or fuel sender and fuel pump harness
6
connector and ground.

Replace the fuel gauge sender. Refer to Fuel Pump

7 Replacement.
1998 -
MD-lsuzu
Gauge -
Fuel Always Indicates Full (Dual Tanks)
1. Disconnect harness connector at fuel sender and
balance pump control module
1
2. Connect a fused jumper from CKT 30 (PPL) wire at
harness connector to chassis ground.

Does fuel gauge indicate FULL? Go to Step 2 Go to Step 4
Locate and repair open in CKT 30 (PPL) wire from the

fuel sender and balance pump control module harness
2
connector to instrument cluster harness connector.

Is repair complete? System OK Go to step 3

Connect a fused jumper from CKT 30 (PPL) wire to
CKT 350 (BLK) wire at fuel sender and balance pump
4
control module harness connector.

Locate and repair open in CKT 350 (BLK) wire from the
5
connector to splice S413.

1. Connect a jumper from CKT 1936 (DK BLU) wire to

CKT 30 (PPL) wire at fuel sender and balance pump
2. Disconnect connector at left hand fuel tank.

6
3. Connect a fused jumper from CKT 1936 (DK BLU)

wire at left hand fuel tank harness connector to
chassis ground.
Locate and repair open in CKT 1936 (DK BLU) wire
7 harness connector and the left hand fuel tank harness
connector.
1. Connect a fused jumper from CKT1936 (DK BLU) to
CKT 350 (BLK) wire at the left hand fuel tank
connector.
8 Connect a jumper from CKT 1936 (DK BLU) to
2.


Locate and repair open in CKT 350 (BLK) wire between
9
connector and splice S413.

1. Connect a jumper from CKT 1937 (LT BLU) to

10 2. Disconnect connector at right hand fuel tank.
3. Connect a fused jumper from CKT 1937 (LT BLU)

wire at harness connector to chassis ground.
7998 -
MD-lsuzu
Gauge -
Fuel Always Indicates Full (Dual Tanks) (cont'd)
Locate and repair open in CKT 1937 (LT BLU) wire
11 harness connector and right hand fuel tank harness
connector.
1. Connecta fused jumper from CKT 1937 (LT BLU) to
CKT 350 (BLK) wire at the right hand fuel tank

connector.
12 2. Connect a jumper from to CKT 1937 (LT BLU) wire
to CKT 30 (PPL) wire at fuel sender and balance

pump control module harness connector.
Locate and repair open in CKT 350 (BLK) wire from the
13
connector to G404.
1. Visually determine approximate fuel level in right
hand and left hand fuel tanks.
2. Use ohmmeter to check resistance between
CKT 350 (BLK) and CKT 1937 (LT BLU) or
CKT 1936 (DK BLU) wires on the fuel senders on
each fuel tank.
14 An empty tank would indicate low resistance
(approximately one ohm).

A full tank would indicate high resistance
(approximately 88 ohms).
A partially full tank would indicate somewhere
between those values.
Is sender resistance good? Go to Step 15 Go to Step 16
Replace fuel sender and balance pump control module.

15
Replace the applicable sender unit. Refer to Fuel Pump

16 Replacement
Gauge -
Fuel Inaccurate or Inoperative (Single Tank)
DEFINITION: The fuel reading on the gauge does not correspond with the fuel level in the tank.
1. Disconnect the fuel sender or fuel sender and fuel

pump harness connector.
2. Connect the red lead of the fuel pump tester
J33431-B to CKT30 (Ppl) and the other lead to
ground.
1,
4. Set the resistance dial to 00 and then to 900. Fuel

gauge shiuld indicate empty and then full. (Allow
time for gauge to reach FULL due to anti -slosh
device.
Does the gauge respond correctly? Go to Step 2 Go to Step 5
Check CKT350 (BIk) from fuel sender or fuel sender and
2 fuel pump to ground for high resistance.
Is resistance high? Go to Step 3 Go to Step 4
W98 -
MD-ISUZU
Gauge -
Fuel Inaccurate or Inoperative (Single Tank) (cont'd)
Repair or replace CKT350 (BIk) between the fuel tank and
3 ground.
Replace the fuel sender. Refer to Fuel Pump Replacement.

4

Check CKT30 (Ppl) for high resistance between the fuel
5 sender and the IP cluster connector.
Is the resistance high? Go to Step 6 Go to Step 7

Repair or replace CKT30 (Ppl) between the fuel tank and
6 the IP cluster.

Gauge -
Fuel Inaccurate or Inoperative (Dual Tanks)
1. Remove the connector from the fuel sender and
balance pump control module.
2. Connect a fused jumper between the terminal C and

terminal F at the fuel sender and balance pump
1
Place ignition switch in RUN. Note: Allow time for

3.
the gauge to reach its final position due to the
anti-slosh device.
Did the gauge indicate approximately the capicity of the
LH fuel tank? Go to Step 9 Go to Step 2
1. Remove the connector from the LH fuel sender and

fuel pump.
2. Connect one lead of tester J-33431-B to the

CKT 1936 (DK BLU) and the other end to chassis
ground.
2
3. Set the resistance to Oi2 and then to 90C2. Fuel

gauge should indicate EMPTY and then FULL. Note:
Allow time for the gauge to reach FULL due to the
anti-slosh device.
Did the gauge respond correctly? Go to Step 3 Go to Step 6
Check CKT350 (BLK) for high resistance between the LH
3 tank connector and chassis ground.
Was there high resistance in CKT350? Go to Step 5 Go to Step 4
Replace the fuel gauge sender. Refer to Fuel Pump

4 Replacement.
Repair or replace CKT350 (BLK) between thr LH fuel tank

5 connector and chassis ground.
1998 -
MD-lsuzu
Gauge -
Fuel Inaccurate or Inoperative (Dual Tanks) (cont'd)
1. Check for high resistance in CKT30 (PPL) between
the fuel sender and balance pump control module
harness connector and the IP.
6 Check for high resistance in CKT1936 (DK BLU)
2.
between the fuel sender and balance pump control

module harness connector and the LH fuel tank.
Did either circuit show high resistance? Go to Step 7 Go to Step 8
Repair or replace CKT30 (PPL) or CKT1936 (DK BLU).
7


1. Remove the jumper wire.
2. Install the jumper between terminal B amd terminal F
at the fuel sender and balance pump control module
harness connector.
9
3. Place the ignition switch in RUN. Note: Allow time
for the gauge to reach final position due to

anti-sloshing device.
Does the gauge indicate the approximate capacity of the
RH fuel tank? Go to Step 10 Go to Step 11
10

1. Remove the RH fuel sender and fuel pump
connector.
2. Connect one lead of J-33431-B to CKT1937
(LT BLU) and the other to chassis ground.
11
3. Set the resistance to OQ and then to 90S1. Fuel
gauge should indicate EMPTY and then FULL.

Note: Allow time for gauge to reach final position
due to anti-slosh device.
Did the gauge respond correctly? Go to Step 12 Go to Step 15
Check CKT 350 (BLK) for high resistance between the
12 LH tank connector and ground.
Is there high resistance in CKT350? Go to Step 13 Go to Step 14

Repair or replace CKT350 between the LH tank connector
13 and ground.

Locate and repair the open CKT1937 (LT BLU) between

in
15
connector and th RH fuel tank harness connector.

1998 -
MD-lsuzu
Gauge -
Fuel Inaccurate or Inoperative (Vehicle Runs Out at Half Tank)
1. Remove connector at the fuel sender and fuel
pump, RH.
2. Connect a fused jumper between the fuel sender and
fuel pump terminal A on the tank, and chassis
1
ground.
3. Connect a fused jumper from B+ to terminal C at the
fuel sender and fuel pump connector at the fuel tank.
Does the fuel pump run? Go to Step 3 Go to Step 2

Connect aself powered test lamp between the fuel sender
and fuel pump harness connector terminal A, and chassis
3
ground.
Locate and repair the open in CKT350 (BLK) between the
4 fuel sender and fuel pump harness connector and G404.

1. Remove the fuel transfer pump relay from its socket.
2. Connect a self powered test lamp between fuel
5 transfer pump relay socket terminal 87 and fuel
sender and fuel pump connector terminal C.

Locate and repair CKT458 (YEL) between the fuel sender
6 and fuel pump, and the fuel transfer pump relay.
1. Connect a test lamp between the fuel transfer pump

relay socket terminal 30 and chassis ground.
7

Locate and repair the open in CKT341 (BRN) between the

8 IP fuse block and the fuel transfer pump relay.

1. Remove the fuel pump relay from the socket in the
relay center.
9 2. Connect a self powered test lamp between the fuel
pump relay terminal N1 and fuel transfer pump relay

terminal 85.
Locate and repair the open in CKT120 (GRY) between
10 S406 and the fuel transfer pump relay.
1. Remove the connector at the fuel sender and

balance pump control module.
11 2. Connect a self powered test lamp between the fuel
transfer pump relay socket terminal 86 and the fuel

sender and balance pump control module terminal D.
1998 -
MD-lsuzu
Gauge -
Fuel Inaccurate or Inoperative (Vehicle Runs Out at Half Tank) (cont'd)
Locate and repair the open in CKT497 (LT GRN) between
the fuel sender and balance pump control module and the
12
fuel transfer pump relay.


1. Replace the fuel transfer pump relay in its socket.
2. Connect a fused jumper between the fuel sender and

balance pump control module connector terminal D
and chassis ground.
13 3. Connect a test lamp between the fuel sender and

fuel pump connector terminal C and ground.
4. Place the ignition switch in RUN. Note: the circuit will

be energized for approximately 2 seconds.
Replace the fuel transfer pump relay.
14

Connecta test lamp between the fuel sender and balance
pump control module connector terminal A and chassis

15
ground.
Locate and repair the open in CKT341 (BRN) between
S415 and the fuel sender and balance pump control
16
module.
Connect a self powered test lamp between the fuel sender
and balance pump control module connector terminal E
17
and chassis groung.

18

Locate and repair the open in CKT350 (BLK) between
S413 and the fuel sender and balance pump control
19
module.
Gauges Inoperative -
All
1. Disconnect the 17-terminal IP cluster connector at


1
Connect a test lamp between CKT 21 (BRN) at the

3.
instrument cluster harness connector terminal C12 to
chassis ground.
Connect a self-powered test lamp between CKT 22 (BLK)
at the instrument cluster connector terminal C15 and
2
ground.
Locate and repair the open in CKT 21 (BRN) between the

IP fuse block circuit breaker #6 and the instrument cluster
3
connector.
1998 -
MD-lsuzu
Gauges Inoperative -
All (cont'd)

Locate and repair the open CKT 22 (BLK) between the
in
4 instrument cluster and joint connector 1, terminal 3F.

5
Gauge -
Voltmeter Inaccurate or Inoperative
2. Check the battery voltage with a voltmeter.
1 3. Compare the instrument cluster voltmeter indication 12V

to the tested voltage.
Are the voltmeter indications approximately the same
within the specified value? System OK Go to Step 2
Indicator -
Check Gauge Always On (Cell 81)
Go to Gauge -
2. Observe the temperature gauge indicator. Engine Oil

1 120-C (245-F)
Does the temperature gauge indicator indicate a Pressure
temperature beyond the specified value? Always High Go to Step 2
Go to Gauge -
2 2. Observe the oil pressure gauge indicator. 34 RPa (5 psi) Engine Oil
Does the oil pressure gauge indicate the pressure is below Pressure
the specified value? Always Low Go to Step 3
1. Disconnect the multifunction alarm module. Go to

Observe the CHECK GAUGES indicator lamp. Multifunction
3 2.
Alarm Module
Is the CHECK GAUGES indicator lamp off?
Replacement. Go to Step 4
1. Disconnect the instrument cluster connector.
4 2. Connect an ohmmeter across instrument cluster
harness connector terminal B8 and ground.

Does the ohmmeter indicate a short to ground? Go to Step 5 Go to Step 6
1. Locate the short in the wire between the

multifunction alarm module and the instrument
5 cluster.
2. Repair the short.

1998 -
MD-lsuzu
Indicator -
Check Gauge Always On (Cell 41)
Disconnect the engine coolant temperature switch.
1
Does the lamp turn off? Go to Step 2 Go to Step 3
Replace the engine coolant temperature switch.

2

Disconnect the oil pressure switch.
3
Does the lamp turn off? Go to Step 4 Go to Step 5
Replace the oil pressure switch.

4

Disconnect the multifunction alarm module.
5
Does the lamp remain on? Go to Step 6 Go to Step 7

Locate and repair the short to ground in CKT 19 or
CKT 607 (BLU/YEL) between the instrument cluster and
6
the multifunction alarm module.

Connect a test lamp from the oil pressure switch
7 connector to B+.
Locate and repair the short to ground in CKT 231

(TAN/BLK) or CKT 608 (BRN/BLK) between the oil
8
pressure switch and the multifunction alarm module.

Connect a test lamp from the engine coolant temperature
9 switch connector to B+.

Locate and repair the short to ground CKT 1675 (BRN)
in
between the engine coolant temperature switch and the

10
multifunction alarm module.

Replace the multifunction alarm module.
11
Indicator -
Check Gauge Inoperative
1. Disconnect the engine coolant temperature switch.
2. Connect a fused jumper from the engine coolant

1 temperature switch connector to chassis ground.

Does the lamp light? Go to Step 2 Go to Step 3
Replace the engine coolant temperature switch.

2
1. Leave the jumper connected.

2. Backprobe the multifunction alarm module with a
3 10.0V
DVM from terminal B7 to B+.
Is the voltage less than the specified value? Go to Step 4 Go to Step 5
1998 -
MD-lsuzu
Indicator -
Check Gauge Inoperative (cont'd)
the multifunction alarm module and the engine coolant
4
temperature switch.
1. Place the ignition switch in the LOCK position.
2. Disconnect the fused jumper.
3. Disconnect the oil pressure switch.

5
Connect a fused jumper from the oil pressure switch

4.
connector to chassis ground.
Replace the oil pressure switch.
6

7 Backprobe the multifunction alarm module with

2. a
DVM from terminal A7 to B+.

10.0V
Is the voltage less than the specified range? Go to Step 8 Go to Step 9
Locate and repair the open in CKT 231 (TAN/BLK) or
CKT 469 (BRN/BLK) between the multifunction alarm
8
module and the oil pressure switch.

2. Disconnect the jumper.
3. Disconnect the multifunction alarm module.

9
Connect a fused jumper from the multifunction alarm

4.
module connector terminal B6 to chassis ground.
Locate and repair the open in CKT 19 or CKT 607

(BLU/YEL) between the instrument cluster and the
10

11
Indicator -
Fasten Safety Belt Always On Indicator -
Fasten Safety Belt Inoperative
Replace the instrument cluster. Refer to IP Cluster Replace the instrument cluster. Refer to IP Cluster
Replacement (Instrument Cluster). This is an ignition Replacement (Instrument Cluster). This is an ignition
switch-initiated, timed indicator that reminds the switch-initiated, timed indicator that reminds the
driver to fasten the seat belts. driver to fasten the seat belts.
7998 -
MD-lsuzu
Indicator -
Low Engine Coolant Always On
1. Disconnect the low coolant probe.
1
Does the lamp remain lit or light up? Go to Step 3 Go to Step 2

Replace the low coolant probe.
2

Backprobe the multifunction alarm module with a DVM
3 from terminal B1 to B+. 1.0V
Is the voltage more than the specified range? Go to Step 4 Go to Step 5
Locate and repair the short to ground in CKT 601 or
CKT 1478 (LT GRN) between the low coolant probe and
4

5

Does the lamp remain lit? Go to Step 6 Go to Step 7
Locate and repair the short to voltage in CKT 15 or

CKT 603 (YEL/RED) between the instrument cluster and
6

7
Indicator -
Low Engine Coolant Inoperative (Cell 41)
Backprobe the low coolant probe connector with a DVM

1 from terminal B to B+. 10.0V
2 low coolant probe and G107.
1. Disconnect the low coolant probe.
2. Connect a fused jumper from the low coolant probe

3 connector terminal B to A.

Does the lamp turn on? Go to Step 4 Go to Step 5
Replace the low coolant probe.

4

2. Backprobe the multifunction alarm module with a
5 DVM from terminal B to B+. 10.0V

1998 -
MO-ISUZU
Indicator -
Low Engine Coolant Inoperative (Cell 41) (cont'd)
(LT GRN) between the low coolant probe and the
6

7 3. Disconnect the fused jumper.
4. Connect a fused jumper from the multifunction alarm

module connector terminal B2 to B+.

(YEL/RED) between the instrument cluster and the
8

9
Indicator -
Low Engine Coolant Inoperative (Cell 81)
1. Disconnect the instrument cluster connector.
2. Connect a voltmeter between the harness connector

1 terminal B5 for CKT 483 or CKT 15 (YEL/RED) and
ground.
Does the voltmeter indicate battery voltage? Go to Step 2 Go to Step 4
1. Disconnect the multifunction alarm module connector.
2 2. Connect a voltmeter across the multifunction alarm
module harness terminal B2 and ground.

Does the voltmeter indicate battery voltage? Go to Step 3 Go to Step 5
Repair the short to the battery in CKT 483 or CKT 15
between the instrument cluster and the multifunction alarm
3
module terminal B2.


Replace the multifunction alarm module. Refer to
5 Multifunction Alarm Module Replacement.
1998 -
MD-lsuzu
Speedometer Inaccurate (J 38522 Unavailable)

Check that the speedo adapter is correctly calibrated for
1 the axle ratio and the tire size.
Is the condition resolved? System OK Go to Step 2
1. Connect a scan tool in order to monitor the
vehicle speed.
2. Drive the vehicle over a known distance:

Maintain a distance of 8 km (5 mi) or more.
.
Maintain a speed of 80-110 km/h (50-65 mph), if
practical.
3. Using a scan tool, compare the indicated speed to

2 the speedometer indication.
4. Record the following specifications:
. The initial odometer reading
The final odometer reading
The actual distance driven Go to IP Cluster
While at the specified speed, are the scan tool and Replacement
the speedometer readings within 6 km/h (4 mph) of (Instrument
each other? Go to Step 3 Cluster).
Divide the actual distance driven by the distance driven as Go to IP Cluster
indicated by the odometer. Replacement
3 0.96-1.04
Is the indicated ratio within the specified range? (Instrument
System OK Cluster).
Speedometer and/or Odometer Inoperative

Perform diagnostic testing per BRAKES and ENGINE
CONTROLS. This testing will identify problems with the
1
vehicle speed sensor or the speedo adapter.

Is the problem resolved? Go to Step 2 Go to Step 3
System is operating properly.
2
1. Disconnect the connector at the instrument cluster.
2. Disconnect the connector at the speedo adapter.

a self-powered test lamp between the
3 3. Connect
instrument cluster connector terminal D for CKT 42

(WHT) and CKT 422 (WHT) and ground.
Locate and repair the short to ground on CKT 42 (WHT)

and CKT 422 (WHT) between the speedo adapter and the
4
instrument cluster.
Connect a self-powered test lamp between the
instrument cluster connector terminal D and the speedo

5 adapter connector terminal B8 for CKT 42 (WHT) and
CKT 422 (WHT).

1998 -
MD-lsuzu
Speedometer and/or Odometer Inoperative (cont'd)


6
Locate and repair the open in the CKT 42 (WHT) and

CKT 422 (WHT) between the speedo adapter and the
7
instrument cluster.
Tachometer Inoperative
1. Disconnect the 17 way IP harness connector (C3) at

1 Connect a voltmeter across the harness connector
2.


Does the voltmeter indicate DC voltage? Go to Step 2 Go to Step 3
2
1. Disconnect the engine control module connector.
3 2. Connect an ohmmeter across the instrument cluster
harness connector 17 and ground.

Does the ohmmeter indicate a short to ground? Go to Step 4 Go to Step 5
Locate and repair the short in CKT 211 and CKT 19

(WHT) between the instrument cluster and the engine
4
control module.
Connect an ohmmeter across the instrument cluster
harness connector 17 and the engine control module
5
harness connector terminal 69.

Does the ohmmeter indicate a short? Go to Step 6 Go to Step 7
Replace the engine control module.
6
Locate and repair the open in CKT 121 and CKT 19

(WHT) between the instrument cluster and the engine
7
control module.
Audible Warnings Schematic References

Subsection Name
Headlamps: Daytime Running Lamps Cell 102 8Lighting Systems
Interior Lamps Cell 114 8Lighting Systems
7998 -
MO-ISUZU
dy and Accessories Instrument Panel, Gauges and Console 8-329
^ a
fit
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I -
MD-lsuzu

Procedures
Audible Warnings Components

Door Open On the steering Column (part of the Audible Warnings Audible Warnings
Reminder Alarm multifunction switch) Component Views Connector End Views
Lights On On the steering Column (part of the Audible Warnings Audible Warnings
Reminder Alarm multifunction switch) Component Views Connector End Views
Multifunction Alarm
Audible Warnings Audible Warnings
Module (MFAM) Under the right seat
(Air Brakes)
Multifunction Alarm
Module (MFAM) Under the right seat
(Hydraulic Brakes)
Multifunction Alarm
Module (MFAM) C1 On the lower IP harness to the MFAM
(16 cavities) (Air Brakes)
Multifunction Alarm
Module (MFAM) C1 Audible Warnings Audible Warnings
On the lower IP harness to the MFAM
(16 cavities) (Hydraulic Component Views Connector End Views
Brakes)
Multifunction Alarm
Module (MFAM) C2
(2 cavities) (with On the lower IP harness to the MFAM
Automatic Engine
Shutdown)
1998 -
MD-lsuzu
>dy and Panel, Gauges and Console 8-331
Accessories____________Instrument
idible Warnings Component Views
228426
gend
8 -
MD-lsuzu
228786
Legend
(1) Lower IP Harness (7) Pre Stroke Power Cut Relay Fusible
(2) Inverting Driver Module Connector Link, 30 A
(ABS-Hydraulic) (8) Engine Control Module
(3) Inverting Driver Module (ABS-Hydraulic) (9) Engine Control Module Connector C2
(4) Multifunction Alarm Module (80 cavities)
(5) Ignition Main Relay (10) Engine Control Module Connector C1
(40 cavities)
(6) Speedo Adapter (Vehicle Speed Sensor
(VSS) Buffer)
7998 -
MD-lsuzu
Audible Warnings Connector End Views Multifunction Alarm Module (MFAM)

(Hydraulic)
Multifunction Alarm Module (MFAM)
(Air Brakes)
r~^
r~^-
A8 A7 A6 A5 A4
d
A3
I-
A2 A1
A8 A7 A6 A5 A4 ^^
A3 A2 A1
B8 B7 B6 B5 B4 B3 B2 B1
B8 B7 B6 B5 B4 B3 B2 B1
73152
Connector Part
12084944
7 3152
Information
ASM 16F MIC/P 100 (BLK)
Connector Part 12084944
Circuit
Information ASM 16F MIC/P 100 (BLK) Pin Wire Color Function
No.
Circuit A1 LT BLU 475 Brake (Hydraulic)
A2 YEL 468 M.F.A.M. Pin-A2
A1-A4
Not Used
A3 WHT 478 Stoplamp Switch Input
A5 PNK 611 Fused Output Ignition
A4 ORN/BLK 487 Starter Input
A6
Not Used
A5 PNK 480 Fused Output Ignition
A7 BRN/BLK 610 Low Oil Pressure Switch
Primary Brake Indicator
A8 BLK 605 A6 BRN/WHT 482
Ground Lamp Output
B1 LTGRN 601 Low Coolant Probe A7 BRN/BLK 466 Low Oil Pressure Switch
Low Ccaolant Indicator A8 BLK 485 Ground Buss
B2 YEL/RED 603
Lamp
B1 LTGRN 481 Low Coolant Probe
B3-B4
Not used
Low Coolant
BRN/WHT 602 B2 YEL/RED 483
B5 Low Air Switch Indicator Lamp
Check Gauges Auxiliary Brake
B6 BLU/YEL 607 B3 YEL/BLK 484
Coolan t Temperature B4 WHT 477 Stoplamp Switch Input
B7 BRN 609
Switch
B5
Not Used
B8
Not Used
Check Gauges
B6 BLU/YEL 488
Indicator Lamp
Coolant Temperature
B7 BRN 465
Switch
B8 ORN/BLUL 476 Fuse Output Battery
1998 -
MD-lsuzu
Multifunction Alarm Module (MFAM) C2 Audible Warnings Diagnostic

w/ Auto Engine Shutdown System Check
1. Check the condition of circuit breakers #6, #7,
and #19. If any circuit breaker is open, locate and
repair cause of overload. Replace the circuit breaker

/
InhL
^d
n
1=L-
if necessary.
2. Check that G105 is clean and tight.

3. Check that the LH door jamb switch operates
E^ freely.
4. Check that the tail lamps are working properly.
[D^ J
Refer to Cell 110 (Exterior Lighting) for diagnostics of
the tail lamps circuit.
\-
5. Check for a broken, or partially broken wire inside
the insulation which could cause system malfunction
but prove good in a continuity/voltage check with the
280782
system disconnected. These circuits may be
12064760 intermittent or resistive when loaded, and if possible,
Connector Part should be checked by monitoring for a voltage drop
Information
4 Way F Metri-Pack
150 Series (BLK) with the system operational (under load).
Circuit 6. Check for the proper installation of aftermarket

Pin Wire Color Function electronic equipment which may affect the integrity of
No.
other systems. Refer to Checking Aftermarket
A LTBLU 252 Engine Stop
Accessories.
B-C
Not Used
Engine Coolant
D GRN 65 Temperature Switch
(Engine Shutdown)
Chime Always On
Remove the door jamb switch connector.
1
Does the audible warning remain ON? Go to Step 3 Go to Step 2
Replace the door jamb switch.

2

Is the repair completed? System OK

1. Remove the combination switch connector C1.
3 2. Connect a self powered test lamp from CKT 152
(RED/BLK) at combination switch to ground.

Replace the combination switch.
4

Locate and repair the short to ground in CKT 152,
CKT 148, and CKT 26 (RED/BLK) between the combinaton
5

switch and the door jamb switch.

1998 -
MD-lsuzu
Chime Inoperative
1. Remove the connector at the combination switch.
1 2. Connect a test lamp between the combination switch
(terminal 13) and ground.

1. Connect a test lamp from CKT 83 (BRN) at the

combination switch connector C1 (terminal 11) to
2 ground.
2. Turn the ignition switch to the ON position.

Locate and repair the open in CKT 84 and CKT 150
(ORN) between the IP Fuse Block and the combination
3
switch.
Connect a self powered test lamp from CKT 87 (BLK) at

the combination switch connector C1 (terminal 1) to
4
ground.
Locate and repair the open in CKT 83 and CKT 371 (BRN)
5 between the IP fuse block and the combination switch.
1. Connect a self powered test lamp from CKT 152
(RED/BLK) at the combination switch connector C1

6 (terminal 14) to ground.
2. Open the driver's door.

Locate and repair the open in CKT 87, CKT 68, CKT 21
or CKT 550 (BLK) between the combination switch and
7
ground G105.
Replace the combination switch assembly.

8
Connect a self powered test lamp from the combination

9 switch (terminal 14) to the left door jamb switch connector.

10

switch connector C1 (terminal 14) to the connector C210
11
(Terminal 4).
Locate and repair the open in CKT 26 (RED/BLK) between

12 the connector C210 and the door jamb switch.

switch connector C1 (terminal 14) to the diode module
13 (terminal 1H).


14 between the diode module and the connector C210.
1998 -
MD-ISUZU
Chime Inoperative (cont'd)

switch connector (terminal 14) to the diode module
15
(terminal 1G).


Replace the diode module.
16

17 between the combination switch and the diode module.
Fasten Safety Belt Chime Always On

Remove the door jamb switch connector.
1
Does the audible warning remain on? Go to Step 2 Go to Step 3

1. Remove the combination switch connector C1.
2 2. Connect a self powered test lamp from CKT 152
(RED/BLK) at the combination switch to ground.

3
Locate and repair the short to ground in CKT 152,

CKT 148 or CKT 26 (RED/BLK) between the combination
4
switch and the door jamb switch.

Replace the combination switch.
5
1998 -
MD-lsuzu
Repair Instructions
IP Cluster Replacement
(Instrument Cluster)
Removal Procedure
215548
2. Remove the cluster screws.

3. Disconnect the electrical connector.
215553
1. Connect the electrical connector.
2. Install the cluster screws
1998 -
MD-ISUZU
215548
IP Cluster Replacement (Speedometer)
Removal Procedure
2. Remove the cluster.
3. Remove the speedometer screws.
215557
2. Install the speedometer screws.
3. Install the cluster.
^~a
215557
1998 -
MD-lsuzu
Cigar Lighter Replacement

Removal Procedure
1. Remove the lower instrument panel trim.
3. Remove the lighter housing.
1. Install the lighter housing.

3. Install the lower instrument panel trim.
Engine Oil Pressure Switch Replacement

Removal Procedure
1. Disconnect the electrical connector from the
sender.
2. Remove the oil pressure sender from the
engine block.
215560
1. Install the oil pressure sender to the
engine block.
and Notices.
2. Connect the electrical connector to the sender.
Tighten
Tighten the oil pressure sender to 13 N.m
(115 Ibin).
215560
1998 -
MD-ISUZU
IP Carrier Replacement
Removal Procedure
2. Remove the instrument cluster trim.
214649
3. Remove the instrument cluster (2).

4. Disconnect the instrument cluster electrical
connector.
214655
5. Remove the speedometer (3).

6. Disconnect the speedometer electrical
connector.
7. Remove the trim surrounding the radio and the
climate control assembly.
214657
1998 -
MD-lsuzu
8. Remove the right and left lower assist handles

and the lower assist handle trim.
214665
9. Remove the right side lower instrument

panel trim.
10. Carefully pry up the defroster grilles and
remove them.
214669
11. Remove the upper instrument panel

retaining bolts.
12. Remove the instrument panel upper trim (4).
214660
199B -
MD-lsuzu
342 Instrument Panel, Gauges and Console Body and Accessories
13. Remove the center relay housing (5).

14. Remove the hood release cable handle.
15. Disconnect the instrument panel wiring harness.
16. Remove the instrument panel support.
214662
1. Install the instrument panel support.
2. Connect the instrument panel wiring harness.

3. Install the hood release cable handle.
4. Install the center relay housing (5).
214662
5. Install the instrument panel upper trim (4).
6. Install the upper instrument panel

retaining bolts.
7. Install the defroster grilles.
214660
1998 -
MD-lsuzu
8. Install the right side lower instrument panel trim.
214669
9. Install the right and left lower assist handles

and the lower assist handle trim.
10. Connect the radio and climate control assembly
electrical connector.
11. Install the radio and climate control assembly.
12. Install the trim surrounding the radio and
climate controls.
13. Connect the speedometer electrical connector.
214665
14. Install the speedometer (3).
214657
1998 -
MD-lsuzu
15. Connect the instrument cluster electrical
connector.
16. Install the instrument cluster.
214655
17. Install the instrument cluster trim.

214649
1998 -
MD-lsuzu
Multifunction Alarm Module Replacement

Removal Procedure
2. Raise the passenger seat.
3. Disconnect the electrical connector from the
multifunctional alarm module.
4. Remove the three bolts and the multifunctional
alarm module from the seat frame.
216127
Notices.
1. Connect the multifunctional alarm module to the

seat frame with three mounting bolts.
Tighten
Tighten the bolts to 3 N.m (27 Ib in).
2. Install the multifunctional alarm module

electrical connector.
3. Lower the passenger seat.
216127
1998 -
MD-lsuzu
Description and Operation Speedometer/Odometer

The speedometer and the odometer operate through
Instrument Cluster Circuit Description solid state circuity inside the instrument cluster. The
IP fuse block circuit breaker #6 powers the
Check Gauges Indicator Lamp
instrument cluster through CKT 41 (BRN). The
The CHECK GAUGES indicator lamp lights when instrument cluster receives a square wave,
either the engine oil pressure is at or below
4,000 pulses per mile signal from the vehicle speed
approximately 34 kPa (5 psi) or whenever the engine sensor (VSS) buffer through CKT 42 and CKT 422
coolant temperature is at or over approximately
(WHT). The solid state electronics position the
118C (245'F), as sent from the malfunction alarm
speedometer pointer in response to the pulse rate.
module. The ignition switch must be in the RUN The electronics also drive the odometer indication in
position in order to power the CHECK GAUGES
response to the pulse rate over time.
lamp driver. Circuit Breaker #6 in the IP fuse block
provides power to the lamp. The lamp driver is The speedometer's rated accuracy at 65 mph is plus
grounded by the multifunction alarm module. The or minus 2 mph (63 to 67 mph). At 20 mph, the
CHECK GAUGES indicator lamp remains lit after the rated accuracy is plus or minus 4 mph (16 to
engine is started until the engine oil pressure 24 mph). Variations in voltage and inaccuracies in
exceeds the low oil pressure setpoint. the other circuit components may increase the error.
Oil Pressure Gauge Tachometer

Battery voltage, from circuit breaker #6 in the IP fuse The timing and injection rate control system (TICS)
block, powers the oil pressure gauge when the module drives the tachometer. The TICS module
ignition switch is in the RUN position. If the current receives the input from the engine speed sensor and
through the oil pressure gauge and the oil pressure generates the tachometer output signal which is sent
sensing element is high, the pointer moves toward to the cluster mounted tachometer.
the 0 kPa (0 psi) indication. If the current through the
gauge and the sensor decreases, the gauge moves Temperature Gauge
toward the 550 kPa (80 psi) indication. The magnetic fields of the two coils, the 38 C
The current that passes through the oil pressure (100'F) coil and the 126'C (260 "F) coil, moves the
gauge passes through two magnetic coils. The pointer of the temperature gauge. The two coils are
vertical coil connects directly to ground. The oriented at right angles so that the magnetic fields
horizontal coil ground path passes through the oil interfere with each other. When the ignition switch is
pressure sensing element. Some of the current in the RUN position, circuit breaker #6 makes battery
always passes through the vertical coil. The voltage available to the instrument cluster through
percentage of total current passing through the CKT 21, CKT 28, CKT 1 or CKT 371 (BRN). If little
horizontal coil depends on the resistance of the oil current flows through the 126'C (260 F) coil, then
pressure sensing element. The oil pressure sensing current flows through the 38 "C (100'F) coil which
element produces a resistance of approximately places the pointer at 38 "C (100'F), low temperature.
0 ohms when the oil pressure is zero. The oil If the current through the 126'C (260'F) coil is high,
pressure sensing element produces a resistance of then the pointer moves toward the 126'C (260'F),
approximately 88 ohms when the oil pressure is at high temperature, indication.
550 kPa (80 psi). With a lower resistance, a greater
The current that passes through the 126'C (260'F)
percentage of the total current passes through the
coil has two paths to ground. Some of the current
horizontal coil and the pointer moves to 0 kPa
(0 psi). When the oil pressure is high, a smaller can pass through the fixed resistance of the 38' C
percentage of the current flows through the oil (100'F) coil and to G101 through CKT 451
pressure gauge horizontal coil and the pointer moves (BLK/WHT). The remainder of the current passes to
toward 550 kPa (80 psi). ground through the variable resistance of the
When the multifunction alarm module senses a high temperature sensor. The engine coolant temperature
gauge sensor produces a resistance of
temperature, (low oil pressure) condition, the
multifunction alarm module grounds the CHECK approximately 1,305 ohms when the temperature is
GAUGES cluster indicator lamp input terminal, B8. 38'C (100'F). With this high resistance, more
The oil pressure setpoint is at approximately current flows through the 38 "C (100'F) coil and the
34 kPa (5 psi). pointer moves toward 38'C (100'F). The resistance
of the sensor is approximately 61.9 ohms at 118'C
The accuracy of the oil pressure gauge is adequate
for normal operator usage because the oil pressure
(245'F). With this low resistance, more current
passes through the temperature sensor and not the
gauge provides a reasonably accurate indication of
the engine oil pressure from which sudden or long 38'C (100'F) coil. The pointer moves toward 126'C
term changes may be identified. The response of the
(260-F).
sensing element is essentially linear over the When the multifunction alarm module senses a high
operating range. The gauge accuracy is for temperature (low oil pressure) condition the MFAM
3.5 degrees (angular) at 0 kPa (80 psi) and for grounds the CHECK GAUGES indicator lamp input
7 degrees at 550 kPa (80 psi). Changes in the terminal, B8. The temperature setpoint is at
battery voltage do not affect the gauge accuracy. approximately 61.9 Ohms or 245'F (118'C).
1998 -
MD-lsuzu
The accuracy of the temperature gauge is adequate Low Air, Low Coolant, and Engine
for the normal operator usage because the Shutdown Module
temperature gauge provides a reasonably accurate
This module applies to vehicles with the optional
indication of the engine coolant temperature from
which sudden or long term changes may be
CHECK GAUGES warning lamp and the engine
identified. The response of the sensing element is shutdown feature.
non-linear over the operating range. This condition This alarm module monitors the following information:
limits accuracy. The gauge accuracy specification is Air brake system pressure
for 3.5 degrees (angular) at 126'C (260 "F) and for
Oil pressure
7 degrees at 38 "C (100'F). Changes in the battery
voltage do not affect the gauge accuracy. Engine coolant temperature

Coolant level
Voltmeter
The module may also shut down the engine under
The voltmeter indicates battery voltage when the
the following conditions:
ignition switch is in the RUN position. The voltmeter
measures generator voltage when the engine is
The engine coolant gets too hot.
running. The normal generator voltage is 14 volts.
The oil pressure drops below a safe level.
The battery voltage without the engine running
The coolant level drops below the level of the
depends upon the ambient temperature. The battery
coolant probe.
voltage may be as low as 9.6 volts. Circuit
If the air brake pressure drops below 503 kPa
breaker #6 supplies voltage to the voltmeter through
CKT 26), CKT 1 or CKT 371 (BRN). Ground for the (73 psi) when the engine is running, the air pressure
single coil indicator passes through CKT 27 (BLK) to switch closes, and the module turns on the
joint connector #1 (upper). PRIMARY BRAKE warning lamp and sounds a
continuous alarm.
Audible Warnings Operation If the engine coolant temperature rises above 107'C
Alarm Systems General Description (225' F), the coolant temperature switch turns on the
CHECK GAUGES warning lamp and sends a signal
Each vehicle has at least one, or possibly several,
to the alarm module and sounds a tone alarm at two
alarm systems that alert the driver to system
beats per second.
malfunctions. At start-up, all of the warning indicators
will turn on as a bulb check. An alarm module If the coolant temperature increases above 111 "C
controls the alarm systems on any vehicle. Refer to (232 F), or if the oil pressure drops below 55 kPa
the following alarm and module information. (8 psi), the CHECK GAUGES warning lamp remains
on and the tone alarm increases to five beats a
Hydraulic Brake Control and Low Coolant
second.
Alarm Module
If the coolant level falls below the level of the
The brake fluid level switch turns on the PRIMARY
BRAKE warning lamp on the instrument panel if the coolant probe, the module allows 25 seconds for any
splashing effect, and then the module sounds a tone
fluid in the brake master cylinder is low. If the flow of
fluid from the power steering pump is low, the alarm at five beats per second. This then turns on
module turns on the PRIMARY BRAKE lamp and the LOW COOLANT warning lamp.
sounds a continuous alarm. The five beats per second tone alarm signals the
If the module detects a malfunction in the auxiliary activation of the engine shutdown system. The
electric pump system, the module turns on the engines runs for 25 seconds before the module
AUX BRAKE warning lamp and sounds a interrupts the current flow through the fuel flow
continuous alarm. solenoid. This shuts down the engine. Restarting the
If the coolant level becomes very low, the module engine resets the timer, but after 25 seconds, the
also turns on the LOW COOLANT warning lamp and engine will again shut off.
sounds an alarm at five beats per second.
Hydraulic Brakes, Low Coolant, and Engine
Low Air (Air Brakes) and Low Coolant Shutdown Module
Alarm Module This module applies to vehicles with the optional
The low air pressure switch turns on the PRIMARY CHECK GAUGES feature.
BRAKE warning lamp when the engine starts, and
the lamp remains on until the system reaches normal The brake fluid level switch turns on the PRIMARY
BRAKE warning lamp on the instrument panel if the
pressure.
fluid in the brake master cylinder is low. If the flow of
If the system air pressure drops below 503 kPa
fluid from the power steering pump is low, the
(73 psi), when the ignition is on, the low air pressure
switch turns on the warning lamp and the module module turns on the PRIMARY BRAKE lamp and
sounds a constant tone alarm. sounds a continuous alarm.
If the coolant level becomes very low, the module If the flow of fluid from the power steering pump is
also turns on the LOW COOLANT warning lamp and low, the module turns on the PRIMARY BRAKE
sounds an alarm at five beats per second. warning lamp and sounds a continuous alarm.
7998 -
MD-lsuzu
If the module detects a malfunction in the auxiliary
Provides
tone signal.
a
electric pump system, the module turns on the AUX

Turns on the tone signal under the following
BRAKE warning lamp and sounds a continuous conditions:
alarm. oil pressure switch indicates low oil
-
The
If the coolant level becomes very low, the module
pressure.
also turns on the LOW COOLANT warning lamp and
sounds an alarm at five beats per second.
-
The temperature switch indicates high engine

coolant temperature.
The module monitors the oil pressure, the coolant
temperature, and the coolant level. The module also
-
The low coolant probe indicates a low

shuts down the engine as described in the air brake, coolant level.
low coolant, and engine shutdown module. The PNK wire provides power to the alarm/brake
booster module, and the BLK wire provides the
Hydraulic Brake Booster Reserve System system ground.
The hydraulic brake booster motor drives a hydraulic During the engine crank mode of operation, input on
pump in order to provide a reserve power source in the YEL wire alerts the module to the START
the event of a loss of primary hydraulic power in the
brake system. process. When the engine starts, the module
receives pulsed signals from the generator. If these
Two electrical switches (flow and stoplamp) control signals are not received, the module will not operate.
the booster motor. The switches are wired in series
through the brake booster relay. During the engine crank mode, the PRIMARY
BRAKE and the AUX BRAKE warning lamps
The flow switch senses fluid flow through the primary
hydraulic power system. If the primary system drops energize for four seconds in order to verify continuity.
Also, during the pre-engine running stage of
below a minimum level (about 0.75-1.50 gallons per
minute), the switch closes and provides a ground operation, the alarm/brake booster module performs
a brake booster system check. Prior to the engine
signal to the coil in the brake booster relay.
running, the flow switch is closed because there is
This ground signal is also applied to the alarm/brake
no primary power steering fluid flow. With the
booster module as a signal that the primary system switch closed, the module senses ground on the
is not operating correctly.
LT BLU/BLK wire. If the switch is stuck open, the
Whenever the brakes are applied, a brake switch
module provides a signal to turn on the AUX BRAKE
inside the stoplamp switch assembly closes. Closing warning lamp. The module will also sound a constant
this switch allows battery voltage from the HYD BRK
tone alarm.
circuit breaker to be applied to the coil of the brake
This ground signal from the flow switch is also sent
booster relay. This battery voltage signal is also
applied to the alarm/brake booster module as an to the brake booster relay on the LT BLU/BLK wire.
input that the brake switch is closed. With the brake switch open, this ground signal
passes through the relay coil to the GRA wire and
The following signals control the brake booster relay:
then to the module. If the module does not sense
Battery voltage input from the brake switch in this ground signal, this indicates an open in the relay
the stoplamp switch coil circuit. The module then provides an output to
A ground signal from the flow switch turn on the AUX BRAKE warning lamp and sounds a
The relay energizes whenever the primary hydraulic constant tone alarm.
booster system is not operating correctly, and the With the brake booster in a de-energized state, the
brakes are applied. Energizing the relay applies module senses a ground signal on the ORN wire
battery voltage to the brake booster motor in order through the motor windings and the BLK wire. If this
to activate the secondary brake booster system.
ground is not sensed, this turns on the AUX BRAKE
The fluid level switch closes when hydraulic fluid in warning lamp and sounds a tone alarm.
the reservoir drops below the switch level. The
ground signal from the switch turns on the PRIMARY When the engine is running, and the pulsed signal is
BRAKE warning lamp in order to alert the driver of a received from the generator on the YEL wire, the
low fluid condition. module changes to RUN mode monitoring. If the flow
switch does not open when the engine is running,
Alarm/Brake Booster Module with the module provides an output turning on the AUX
Hydraulic Brakes BRAKE warning lamp. This also sounds a constant
The alarm/brake booster module performs the tone alarm. If the ground signal on the ORN wire to
following functions: the module stops, this indicates an open in the
circuit through the motor windings to ground. The

Monitors the primary and the secondary
hydraulic brake booster systems. AUX BRAKE warning lamp then comes on and
sounds a constant tone alarm.

Monitors the output from the following switches:
If the flow switch closes when the engine is running,
- Oil pressure
the module provides an output turning on the
-
Coolant temperature PRIMARY BRAKE warning lamp and sounds a

-
Coolant Level constant tone alarm.
7998 -
MD-lsuzu
Also, during the engine-running mode of operation Engine Low Coolant Indicator Probe
and when the brakes are applied, the closed (Diesel Engines Only)
stoplamp switch sends a battery voltage signal to the
The engine low coolant indicator probe is part of the
alarm/brake booster module on the GRA wire. At the
coolant surge tank. If the engine low coolant
same time, the module senses battery voltage on the indicator does not function properly, replace the
WHT wire from the brake switch. If the battery coolant surge tank. Refer to Surge Tank (Diesel)
voltage signal is not sensed, this indicates an open Replacement in Engine Cooling.
in the GRA wire to the brake booster relay. If this
condition occurs, the module provides an output to Engine Alarm System
turn on the AUX BRAKE warning lamp and sounds a
The alarm/brake booster module operates as a
constant tone alarm. monitor for the primary and the secondary hydraulic
brake booster systems. The module also monitors
Check Gauges Module
the following outputs:
The alarm/brake booster module operates as a oil pressure switch

The
monitor for the primary and the secondary hydraulic
brake booster systems. This module also monitors
The coolant temperature switch
the following outputs: The coolant level switch

The oil pressure switch The module provides a tone signal and turns on the
tone signal under the following conditions:

.
The coolant temperature switch

The oil pressure switch indicates low oil

The coolant level switch
pressure.
The module provides a tone signal and turns on the

The temperature switch indicates high engine
tone signal under the following conditions:
coolant temperature.

The oil pressure switch indicates low oil
.
The low coolant probe indicates a low level of
pressure.
coolant.

The temperature switch indicates high engine The alarm module also turns on the CHECK
coolant temperature. GAUGES lamp. This tone signal is on a 50 percent

The low coolant probe indicates a low level of duty cycle.
coolant.
The alarm module also turns on the CHECK Engine Alarm/Shutdown System
GAUGES lamp. This tone signal is on a 50 percent (Diesel Engines Only)
duty cycle. This optional system monitors the following
information:
Air Brake Alarm System
Engine coolant level
This alarm module monitors air pressure through the
Coolant temperature
air pressure switch.
Oil pressure
Whenever the engine and the air
is running,
If the engines encounters a high temperature or a
pressure drops below 455 kPa (73 psi), the air
low pressure condition, the CHECK GAUGES
pressure switch closes. The LOW AIR warning
warning lamp comes on and the switches send a
lamp then turns on and the module sounds a signal to the alarm module in order to activate the
continuous alarm.
tone alarm. The alarm sounds at two beats
per second.
Low Coolant Alarm System
A coolant probe in the radiator surge tank uses However, this system may also shut down the
engine should the following conditions occur:
coolant in order to provide a constant ground for
alternating current. The low coolant circuit in the
The engine coolant gets too hot.
alarm module then changes the direct current from
The oil pressure drops below a safe level.
the vehicle electrical system into alternating current.
The coolant level drops below the level of the
The module then activates a 25 second timer, coolant probe.
providing a ground for the tone alarm and the circuit If the oil pressure drops below 41 kPa (6 psi), the oil
for the LOW COOLANT warning lamp in the
pressure switch closes. If the coolant temperature
instrument cluster. The lamp then turns on and a
increases above 103"C (232T), the coolant
tone alarm sounds at five beats per second. temperature switch closes. Either, or both, of these
The module has a built-in 25 second delay in order conditions sound a tone alarm at five beats
to compensate for the effects of coolant splashing in per second.
the radiator and the surge tank. If the coolant level drops below the coolant probe,
the module allows 25 seconds for any splashing
effects and then sounds the tone alarm at five beats
per second. -
1998 -
MD-lsuzu
8-350 Instrument Panel, Gauges and and Accessories
Console____________Body
Whenever the tone alarm sounds at five beats per Audible Warnings Circuit Description
second, a 25 second timer in the alarm module
activates. The module then interrupts the current flow Fasten Safety Belt Warning Lamp
through the #1 relay coil, stopping the fuel flow The safety belt lamp on the instrument cluster will
through the solenoid. Then the module shuts down light when the ignition switch turns to the ON
the engine. position. A timer in the instrument cluster controls
You can start the engine again, but the engine will the lamp. After a predetermined time, (approximately
only run for another 25 seconds before the module 5 seconds) the timer turns off and the lamp will
shuts down the engine again. remain off until the next ignition cycle.
Lamps-On Warning Alarm

The lamps-on warning alarm turns on if the
headlamps or the park lamps remain on when the
driver's door opens. The alarm remains displayed
until the lights turn off or the driver's door closes.
1998 -
MD-lsuzu
Body and Accessories Horns 8-351
Horns
Specifications

Specification
Horn Mounting Nut 17N.m 13lbft
Horns Schematic References

Subsection Name
1998 -
MD-lsuzu
Horns Schematics (Cell 40)
| Hot At All Times |
iip

;1) ,
Circuit
Breaker
|
"
FU se
1 BIC
~ ~
";i^011
Combinlation
7 )ck
20A 1 ^ch
i. 1
Fuse'Hoar
20RN 150
fr 1
1
Detais
<- -
-< S219
Cell 11
20RN 169
10,
QOQC s

20RN 169 20RN 171
'30 85 Relay
^ ;
Hom
ftelay
Center
2
0.8 GR N/RED 170

87 86
j
^1 ~~T~ Hom
2GRK4 172
i.^C200
1E P100
1BLK
(HI
W
-1-
1D KGRN 29
1DK GRN 29
| Single Hom| 4 ,
|Dual Hor E] C101
^f i > S100 S1011

B
1 DK GRN 29 1DKGRN 29
1DK GRN 29
Horn
B
c, rs13:.
^ Horn
1BLK
A
'
î
Ground
Distribution
fall U
T
^J
1BLK 150
1 BLK C105 1 BLK "5r
S105 T >S103 D
150 o 150 GC
8 BLK 150
1
.
t G107
Ground
Distribution
Cell 14
Component Locator
Horns Components
In the center of the lower IP, behind the
Horn Relay Horns Component Views
panel, in the relay center 2

Horn Switch In the steering wheel Horns Component Views
Behind the left side of the front bumper Horns Connector

Horn, A-Note (High) Horns Component Views
impact bar End Views
Horn, A-Note (High) Behind the left side of the front bumper Horns Connector
Horns Component Views
(Dual Electric Horns) impact bar End Views
Horn, F-Note (Low) Behind the left side of the front bumper Horns Connector
(Dual Electric Horns) impact bar End Views

231681
Legend
(1) Relay Center 2 (2) Turn/Hazard Flasher Module
1998 -
MD-lsuzu
8-354 Horns Body and Accessories
Instrument Panel
231673
Legend
(1) Tachometer (4) IP Lamps Dimmer Control
(2) Horn Switch (5) Right Multifunction Lever
(3) Speedometer
1998 -
MO-lsuzu
Underhood View
231456
Legend
(1) Windshield Wiper Motor (3) Windshield Washer Pump Motor
(2) Windshield Wiper Motor Connector
1998 -
MD-ISUZU
Single and Dual Electric Horns Wiring
231467
Legend
(1) Front Chassis Harness (Dual Electric Horns) (4) High-A Note (Dual Electric Horns)
(2) Front Chassis Harness (5) Low F-Note Horn (Dual Electric Horns)
(Single Electric Horn) (6) Dual Electric Horns Harness
(3) High A-Note Horn (Single Electric Horn)
1998 -
MD-lsuzu
Horns Connector End Views
Horn
A B
35437
Connector Part
12052644
Information
ASM 2F M/P 250 (GRY)
Circuit
A BLK 150 Ground
B DKGRN 29 Horn Feed
Horns Inoperative (Both Do Not Sound)

Use a test lamp in order to backprobe the relay center 2
1 from the horn relay terminal 30 to ground.

2 from the horn relay terminal 85 to ground.

from the horn relay terminal 86 to B+, while pressing the
3
horn switch.

from the horn relay terminal 87 to ground, while pressing
4
the horn switch.

Use a test lamp in order to backprobe the horn from
terminal 29 (DK GRN) to ground, while pressing the horn
5
switch.
Use a test lamp in order to backprobe the horn from
6 CKT150 (BLK) to B+.
Use a test lamp in order to backprobe the combination

switch connector from terminal 10 to B+, while pressing
7
the horn switch.

1998 -
MD-lsuzu
Horns Inoperative (Both Do Not Sound) (cont'd)

Locate and repair the open CKT 169 and CKT 150
in
8 (ORN) between the IP fuse block and the relay center 2.
-


Locate and repair the open in CKT 171 (ORN) between
9 S285 and the relay center 2.
Replace the horn relay.

10

Locate and repair the open in CKT 29 (DK GRN) between
11 wire relay center 2 and the horn(s).
Replace the horn.

12

Locate and repair the open in CKT 150 (BLK) between
the single horn and G107 or between S101 and G107 for
13
dual horns.
Locate and repair the open in CKT 170 (GRN/RED)

between the relay center 2 and the combination switch
14
connector.
Replace the horn switch.

15
Horns Inoperative (One Does Not Sound)

Use a test lamp in order to backprobe the inoperative horn
from CKT 29 (DK GRN) to ground while pressing the horn
1
switch.
Use a test lamp in order to backprobe the inoperative horn
2 from CKT 150 (BLK) to B+.

Repair the open in CKT 29 (DK GRN) between S100 and
3 the inoperative horn.
Does the dual horn operate properly? System OK

Replace the inoperative horn.
4

Repair the open in CKT 150 (BLK) between the inoperative
5 horn and S101.
Horns Always On
Disconnect the combination switch connector.
1
Did the horn stop? Go to Step 3 Go to Step 2

Remove the horn relay.
2
Did the horn stop? Go to Step 4 Go to Step 5
1998 -
MD-lsuzu
Horns Always On (cont'd)

Replace the horn switch.
3
Does the horn operate property? System OK

a short to ground in CKT 170 (GRN/RED)
Test for
4 between relay center 2 and the horn switch.
Does the horn operate properly? Go to Step 6 Go to Step 7

Locate and repair the short to voltage in CKT 29
5 (DK GRN) between the relay center 2 and the hom(s).
Does the horn operate properly? System OK

Locate and repair the short to ground in CKT 170
6 (GRN/RED) between relay center 2 and the horn(s).
Replace the horn relay.

7
Repair Instructions
Horn Replacement (Single)
Removal Procedure
2. Disconnect the horn wiring harness.
3. Remove the following components from
the horn:

The nut

The washer

The mounting bolt
4. Remove the horn from the mounting bracket.
216297
1. Install the horn to the mounting bracket.
and Notices.
2. Install the following components to the horn:
The mounting bolt

The washer

The nut
Tighten
Tighten the horn mounting nut to 17 N.m
(13lbft).
3. Connect the horn wiring harness.
4. Reconnect the negative battery cable.
216297
1998 -
MD-lsuzu
Horn Replacement (Dual)

Removal Procedure
2. Disconnect the horn wiring harness.
3. Remove the following components from
the horn:
The nut

The washer
The mounting bolt
4. Remove the horn from the mounting bracket.
216288
1. Install the horn to the mounting bracket.
and Notices.
2. Install the following components to the horn:
The mounting bolt

The washer
The nut
Tighten
Tighten the horn mounting nut to 17 N.m
(13lbft).
3. Connect the horn wiring harness.
4. Reconnect the negative battery cable.
216288

Horns Circuit Description
Battery voltage is applied to the horn relay at all
times through circuit breaker #7. When the horn
switch presses, the horn relay coil grounds.
Grounding the horn relay coil energizes the horn
relay. The horn relay contacts close. Voltage is
applied to the horn(s). Because the horn(s) ground
permanently at G107, the horn(s) will continue to
sound as long as the horn switch is pressed.
1998 -
MD-lsuzu
Body and Accessories Exterior Trim 8-361
Exterior Trim
Repair Instructions
Emblem/Nameplate Replacement
1. In order to achieve proper adhesion, apply
name plates in an environment free of dust
or dirt.
2. Clean the area where the replacement item will

be mounted with a suitable solvent such as
flash naphtha or a mixture of 50 percent
isopropyl/alcohol and 50 percent water.
3. Dry the area thoroughly.
4. Keep the body area and name plate at a
temperature range between 26-40'C

(80-105-F).
5. If necessary, carefully heat the body area and
apply heat to the back of the name plate.
6. Remove the protective liner from the emblem.

223324
7. Line the name plate up with the locating holes
in the hood and press into position.
Grille Replacement
Removal Procedure
1.Raise the hood.
2. Remove the grille retaining screws.
3. Remove the grille assembly.
215839
1. Install the grille to the cab.
2. Install the retaining screws.
3. Close the hood.
215839
1998 -
MD-ISUZU
8-362 Exterior Trim Body and Accessories
Washing and Waxing Foreign Material Deposit Removal

Deposits of foreign material that are left on the
Washing
painted surfaces of the vehicle may damage the
Periodic washing is recommended in order to remove finish. These include the following deposits:
build-up residue and in order to eliminate any

Calcium chloride and other salts
weathered appearance.
Ice melting agents

Wash the vehicle in lukewarm or cold water.

Road oil and tar
Do not use hot water or wash the vehicle in
direct sunlight.
Tree sap
. Do not use strong soap or chemical detergents. Bird droppings
Promptly flush all of the cleaning agents from
Chemicals from industrial chimneys
the surface. Do not allow the cleaning agents
Other foreign matter
to dry on the finish. In order to clean these deposits, use cleaners that
Waxing are designed for painted surfaces.
Your authorized dealer offers several polishes and Cleaning Bright Metal Parts
cleaners that have proven value in maintaining Clean bright metal parts regularly with water. Use
original finish appearance and durability. Protect the
chrome cleaner and polish on chrome or stainless
painted body surfaces and the chrome plating by
steel trim, if necessary.
using a coating of wax. Use any good base body
Use special care with aluminum trim. Do not use
wax for painted and chrome surfaces. Apply the wax
immediately after the vehicle has been cleaned. Do auto or chrome polish, steam, or caustic soap to
not apply wax to the vehicle in direct sunlight or in clean aluminum. A coating of wax, rubbed to a high
polish, is recommended for all bright metal parts.
extreme heat. Periods between applications should
be short enough to ensure continuous protection of
the finish.
1998 -
MD-lsuzu
Procedures
Waterleak Test Preparation
Caution: Standard shop practices, particularly
eye protection, should be followed during these
operations to avoid personal injury.
Various methods can be used to check for water
leaks after the window adhesive has been allowed to
dry. Use the generalized testing method whenever
possible since the testing method provides a large
volume of water to a general area without exceeding
the sealing limitations of the glass. Refer to
Generalized Testing. After finding the leak area,
locate the exact entry point by using the water hose
or air hose test. Refer to Air Hose Test.
Repair Instructions
259438
Generalized Testing
2. Position the stands one on each side of the
Checking with the Water Test Stands vehicle. Water spray from the stands should
overlap on the vehicle.
Wateriest Stand Assembly
3. Run the water at a volume of 15 liters
(3.9 gallons) per minute and at a pressure of
138 kPa (20 psi), measured at the nozzle, for at
least four minutes.
4. Have someone inside the cab during the test in
order to check for the location of any leaks.
5. In order to check the windshield, aim the water
spray 30 degrees down and 45 degrees toward
the rear.
Aim at the corner of the windshield.
154169
1. Assemble the water test stands.
1998 -
MD-lsuzu
8-364 Waterleaks Body and Accessories
Air Hose Test

Notice: The air hose test should only be used on
fully cured urethane adhesive. Otherwise, damage
to the urethane adhesive bead could result in
additional leaks.
Put liquid detergent diluted with water in a squirt
bottle.
Have a helper inside the cab with an air hose.
Beginning at the bottom of the window and gradually
moving up the window edges and across the top,
squirt soap solution on the window moldings and the
glass on the outside of the vehicle.
Have a helper aim the compressed air at the same
locations from the inside of the cab.

Do not allow the air pressure from the hose to
exceed 205 kPa (30 psi).
Bubbles will form in the soap solution at the location
of the leak.
203462
In order tocheck the side windows, aim the
6. Stationary Window Waterleak Repair
water spray 30 degrees down and 45 degrees
1. Depending on where the leak is located,
toward the rear.
remove either the trim molding or the headliner
Aim at the center of the rear quarter. in order to repair the leak.
7. In order to check the back window, aim the 2. Determine the source of water entry.
water spray 30 degrees down and 30 degrees
toward the front. 3. If water is leaking at the top edge of the
windshield, reseal the windshield using the 3M
Diagnostic Information and Window-Weld Resealant P/N 08633 and the
applicator gun 3M 06992, or the equivalent.
Procedures Use a "duck bill" applicator tip in order to inject
the sealant under the molded glass seal.
Water Hose Test
Run water through a hose without the nozzle 4. If water is leaking into the vehicle at the sides
of the glass, use the 3M Super Fast urethane
attached. Begin testing at the base of the window or
windshield and slowly move the hose upward and auto glass sealant P/N 08609, or the
equivalent.
across the top. Have someone in the cab watch
for leaks.
1998 -
MD-lsuzu
Body and Accessories Stationary Windows 8-365
Stationary Windows
Repair Instructions
Windshield Upper Reveal Molding
Replacement
Removal Procedure
1. Remove the left and right curtain rails.
2. Remove the upper windshield molding (2) by
carefully pulling the molding from beneath the
windshield sealing strip.
1.Install the upper windshield molding (2) by
pushing the molding underneath the windshield
sealing strip.
2. Install the left and right curtain rails.
214644
1998 -
MD-lsuzu
8-366 Stationary Windows Body and Accessories
Windshield Replacement
Caution: When working with any type of glass,
use approved safety glasses and gloves to
reduce the chance of personal injury.
When replacing a cracked windshield, correct the
condition which caused the crack before installing

the new glass. The cause of the crack may be an
obstruction or high spot somewhere around the
flange of the opening; cracking may not occur until
pressure from the high spot or obstruction becomes
particularly high due to wind, extreme temperature,
or rough terrain.
The glass from a broken windshield may already
have fallen or been removed from the adhesive.

However, remove a cracked or otherwise imperfect
windshield that is still intact.
If a crack extends to the edge of the glass, use a
piece of chalk to mark the point on the cab where
215141 the crack meets the molding. Start at the point
marked when examining the flange of the opening
for a cause of the crack.
Cover the instrument panel and the surrounding
sheet metal with protective covering before removing
the glass.
Removal Procedure
Caution: If broken glass falls into the defroster
outlets, it can be blown into the passenger
compartment and cause injuries. To help avoid
personal injury, cover the defroster outlets before
replacing windows.
Caution: If a window is cracked but still intact, it
should be crisscrossed with masking tape in
order to reduce the risk of damage or personal
injury.
1. Cut the weather strip (1).
2. Use a helper to push the glass out from the
inside.
3. Remove the weather strip.
1998 -
MD-lsuzu
1. Install the weather strip to the glass.
2. When the weather strip and the glass are
assembled together, keep the weather strip
parallel with the glass.
215142
3. Insert string (approximately 5 mm to 6 mm

a
in diameter) in between the lips of the
weather strip. ;
4. After installing the string around one full turn,

leave the string crossed at the bottom center of
the glass approximately 400 mm (15.7 in).
Caution: At least 24 hours are required for
complete curing of repair material. The
repair area should not be physically
disturbed until after that time. Insufficient
curing of urethane adhesive may allow
unrestrained occupants to be ejected from
the vehicle resulting In personal injury.
5. Apply a consistent bead of urethane
adhesive (1) in between the lips of the weather

strip.
215144
6. Align the center of the glass with the body and

hold the glass from the outside.
7. Using a helper inside the cab, pull the string

from the inside toward the center of the glass.
Fit the lips gradually into the body flange.
In order to keep the glass from shifting to

one side, support the glass securely.

8. If the weather strip swells in one area, tap
lightly with a rubber mallet in order to distribute
the weather strip evenly.
215145
1998 -
MD-ISUZU
Quarter Window Replacement

Removal Procedure
Caution: If a window is cracked but still intact, It
should be crisscrossed with masking tape In
Injury.
1. From inside the cab, push the weather strip out
of the body flange at the two corners of the top
edge of the window.
2. Push the glass out gradually from the inside.
When the weather strip and the glass are
a string with a diameter measuring 4 mm

2. Lay
between the lips of the weather strip.
3. After installing the string around one full turn,
leave the string at the bottom center of the
glass approximately 100 mm (4 in).
4. Clean all the dirt off the body flange and the
weather strip.
215148
1998 -
MD-lsuzu
5. Holding the glass from the outside, align the

center of the glass with the body.


7. If the weather strip swells in one area, tap
the weather strip evenly.
Rear Window Replacement

Removal Procedure
Caution: If a window Is cracked but still intact, it
should be crisscrossed with masking tape In
injury.
1. Push the weather strip out of the body flange
at the two corners of the top edge of the
window.
2. Using a helper outside of the cab, push the
glass out gradually from inside the cab.
215146
When the weather strip and the glass are
215153
1998 -
MD-ISUZU
2. Lay a string with a diameter measuring 4 mm

between the lips of the weather strip.
3. After installing the string around one turn, leave
the string crossed at the bottom center of the
glass approximately 200 mm (7.8 in).
215154
4. Holding the glass from the outside, align the

center of the glass with the body.
If the weather strip swells in one
6. area, tap
the strip evenly.
215155
1998 -
MD-ISUZU
Window Polishing 3. Draw a line directly behind the scratches in

order to serve as a guide for locating the
Minor Scratch and Abrasion Removal scratch while polishing.
Minor scratches and abrasions can be removed or 4. Cover the surrounding area with masking paper
reduced by following the procedure below. Use care in order to catch the drippings or the spattered
to prevent distortions of vision. Double vision may polish.
result if an attempt is made to remove deep
5. Dip the felt pad attached to the polisher into
scratches. Deep scratches should not be removed the mixture. Do not submerge the pad or allow
from an area in the driver's line of vision. If deep the pad to stay in the mixture because this may
scratches are present, the window should be loosen the bond between the pad and the
replaced. metal plate.
The polishing procedure that follows was developed
Notice: Never hold the tool in one spot or
using a cerium oxide compound. Follow the
operate the tool on the window any longer than
manufacturer's directions if using other materials.
30 to 45 seconds. If the window becomes hot
The polishing should not be used on deep tinted to touch, let it air cool before proceeding
windows. The coating on the windows could be further. Cooling with cold water may crack
damaged. heated window. Avoid excessive pressure. It
may cause overheating of the window.
Recommended Equipment
6. Polish the scratched area, but note the
A low speed (600-1300 RPM) rotary polisher.
following:
A wool, felt, rotary polishing pad 76 mm (3 in)

Agitate the mixture as often as needed in
in diameter and 51 mm (2 in) thick.
order to maintain the creamy consistency of

Powdered cerium oxide mixed with water. This the compound.
isan abrasive compound.
Use moderate but steady pressure.
. A wide-mouth container to hold the abrasive
Hold the pad flat against the window.
compound.

Use a feather-out motion.
Polishing Procedure Dip the pad into the mixture every
1. Mix at least 44 ml (1.5 oz) of cerium oxide with 15 seconds in order to ensure that the wheel
enough water to obtain a creamy consistency. If and the window are always wet during the
the mixture is too thick, the mixture cakes on polishing operation. A dry pad causes
the felt pad more quickly. If the mixture is too excessive heat to develop.
runny, more polishing time is needed.
Keep the pad free of dirt and other foreign
2. Draw a circle around the scratches on the substances.
opposite side of the window with a marking
7. After removing the scratch, wipe the area clean
crayon, or the equivalent. of any polish.
8. Clean the polishing pad.
1998 -
MD-lsuzu
J 24402-A
Glass Sealant
Removal Knife
3898
J 24709-01
Urethane Glass Sealant

Remover
3899
J 36020
Windshield Remover
204460
1993 -
MD-lsuzu
Body and Accessories Bumpers 8-373
Bumpers
Specifications

Specification
Bumper Brace Bolt 9N.m 80 Ib in
Bumper Energy Absorber Nut 55N.m 41 Ibft

Bumper Facia Nut 12N.m 106 Ib in
Bumper Impact Bar Bolt 67N.m 49 Ibft
Bumper Impact Bar Bracket 162 N.m 120 Ib ft
Repair Instructions
Bumper Replacement -
Front
Removal Procedure
1. Remove the bumper facia.
2. Remove the bumper braces. Have an assistant

support the bumper.
214239
1998 -
MD-lsuzu
8-374 Bumpers Body and Accessories
3. Remove the impact bar.
214233
4. Remove the bumper energy absorber bracket.
214242
5. Remove the bumper impact bar bracket.
214246
1998 -
MD-lsuzu
Body and Accessories Bumpers 8-375
Notices.
1. Install the bumper impact bar bracket.

Tighten
Tighten the bolts to 162 N.m (120 Ib ft).
214246
2. Install the bumper energy absorber bracket.

Have an assistant hold the bumper in place.
Tighten
Tighten the nuts to 55 N.m (41 Ib ft).
214242
3. Install the bumper impact bar.

Tighten
214233
1998 -
MD-lsuzu
8-376 Bumpers Body and Accessories
4. Install the bumper braces.

Tighten
214239
5. Install the bumper facia.

Tighten
Tighten the nuts to 12 N.m (106 Ib in).
214222
1998 -
MD-lsuzu
Body and Accessories Body Front End 8-377
Body Front End

Specifications

Specification
Battery Box Cover Retainer Bolt 30N.m 22lbft
Battery Box to Frame Nut 70N.m 52lbft
Cab Lock Assembly Bolt 40N.m 30lbft
Cab Tilt Support Bolt 45N.m 33lbft
Component Box Nut 70N.m 52lbft
Component Box Support Nut 24N.m 18lbft
Fender Extension Brace Nut 70N.m 52lbft
Fender Extension Bracket Nut 15N.m 11 Ibft
Fender to Cab Bolt 13N.m 115lbin
Front Cab Mount Bolt 162 N.m 119 Ibft
Inner Extension Panel Bolt 9N.m 80 Ib in
Inner Fender Panel Bolt 9 N.m 80 Ib in
Rear Cab Mount Bracket Bolt 15N.m 11 Ibft

Rear Cab Mount Lower Bracket Bolt 93 N.m 69 Ibft
Rear Cab Mount Upper Bracket Nut 215 N.m 159 Ibft
Steering Shaft Bolt 61 N.m 45 Ibft

Torsion Bar Lever Bolt/Nut 37 N.m 27 Ibft
Upper Inner Fender Bolt 9N.m 80 Ib in
Upper Step Nut 23 N.m 17 Ibft
Upper Step Support Bolt 9N.m 80 Ib in
1998 -
MD-lsuzu
t78 Body Front End Body and Accessories
Repair Instructions
Hood Replacement
Removal Procedure
1. Pull the hood release cable inside the cab.
2. Remove the front handle bolt covers.

3. Remove the bolts from the front handles and
remove the hood with the handles attached.
1. Install the front handle bolts.
2. Install the front handle bolt covers.

3. Close the hood.
215586
Hood Latch Replacement

Removal Procedure
1. Raise the hood.
215631
1998 -
MD-lsuzu
2. Remove the hood latch bolts.
215635
3. Remove the hood release lever bolts.
215631
4. Remove the cable assembly.
215656
1998 -
MD-lsuzu
8-380 Body Front End Body and Accessories
1. Install the cable assembly to the cab.
215656
2. Install the hood release lever bolts.
215631
3. Install the hood latch bolts.

4. Close the hood and inspect for proper
engagement of the hood latch.
215634
1998 -
MO-lsuzu
Fender Replacement -
Front
Removal Procedure
1. Remove the fender from the fender brace bolts.
215666
2. Remove the fender to cab bolts.
215669
3. Remove the fender.
215672
1998 -
MD-lsuzu
382 Body Front End Body and Accessories
4. Remove the fender seal.
215668
1. Install the fender seal to rocker panel.
215668
2. Install the fender to the cab.

and Notices.
3. Install the fender to cab bolts.
Tighten
Tighten the fender to cab bolts to 13 N.m
(115lbin).
215672
7998 -
MD-lsuzu
4. Install the fender to the fender brace bolts.
215666
Battery Box Replacement

Removal Procedure
1. Remove the following items from the cover:
. The bolts
The washers
The nuts
The retainer

2. Remove the cover bolts.

3. Remove the cover.
4. Remove the retainers and the battery or
batteries. Refer to Battery Replacement in
Engine Electrical.
5. Remove the battery cables from the battery
box. Refer to Battery Cable Replacement in
Engine Electrical.
6. Remove the following items from the

battery box: 215682

The bolts
. The washers
The nuts
1998 -
MD-lsuzu
Notices.
1. Install the battery box to the frame rail with the
following items:
. The bolts
.
The washers
The nuts
Tighten
Tighten the battery box to the frame nuts to
70 N.m (52 Ib ft).
215681
2. Install the battery or batteries to the box with

the retainers and bolts. Refer to Battery
Replacement in Engine Electrical.
3. Install the battery cables. Refer to Battery
Cable Replacement in Engine Electrical.
4. Install the cover.
5. Install the retainer and the bolt.
Tighten
Tighten the retainer bolts to 30 N.m (22 Ib ft).
215682
Component Box Replacement

Removal Procedure
1. Remove the top and side cover bolts and the
washers.
2. Remove the top cover.
3. Remove the side cover.
4. If it is necessary in order to gain access to the
box, remove the components. Refer to Disc
Brakes or Engine Controls.
5. Remove the following items from the brace:
.
The bolts

The washers

The nuts
6. Remove the following items from the supports:

The bolts

The washers
215689
The nuts
1998 -
MO-lsuzu
7. Remove six bolts and washers from inside the

frame rail.
8. Remove the reinforcements and box sides from
the frame rail.
Notices.
1. Install the box sides and reinforcements to the
frame with six bolts, washers and nuts.
Tighten
Tighten the component box nuts to 70 N.m
(52 Ib ft).
2. Install the components to the box if they have
been removed. Refer to Disc Brakes or Engine
Controls.
3. Install the supports to the frame with the bolts,
the washers and the nuts.
Tighten
Tighten the component box support nuts to
24 N.m (18lbft).
4. Install the brace to the sides with the bolts, the
washers and the nuts. 215689
Tighten
Tighten the component box brace nuts to
45 N.m (33 Ib ft).
5. Install the side cover and the top cover with the
bolts and the washers.
6. Install the retainers to the box with the bolts.

Tighten
Tighten the top and side cover bolts to
30 N.m (22 Ib ft).
Tighten the retainer bolts to 23 N.m
(17lbft).
Cab Replacement
The cab replacement procedure will vary depending
upon the optional equipment on the vehicle. Some
steps required due to optional equipment have been
included, but be sure to check the vehicle for any
special steps it may require. The following
procedures are intended to be used only as a guide.
Important:
Tag all lines, wires, hoses and harnesses
during removal for proper location during
installation.
Block the wheels.

2. Open the hood.
3. Remove the grille.
4. Remove the left and the right headlamp
assemblies.
5. Recover the air conditioning refrigerant.
1998 -
MD-ISUZU
}6 Body Front End Body and Accessories
6. Remove the air conditioning pipes and the

brackets.
7. Drain the coolant.
8.Remove the heater hoses.
9. Remove the ground strap.
10. Remove the main wire harness under the hood.
11. Remove the clutch fluid pipe (if equipped).
12. Disconnect the transmission control cables.
13. Disconnect the parking brake cable.
14. Remove the throttle linkage.
Information.
16. Remove the air brake hoses (if equipped) or

the linkage to the brake master cylinder.
17. Remove the steering shaft at the steering gear.
Mark the shaft and the gear in order to aid in
reassembly.
18. Remove the cab lock cover.
19. Fasten a rope securely to the cab lock. Use a
hoist or chain block in order to keep the cab
tilted.
20. Remove the torsion bar levers.
21. Remove the cab tilt support.
22. Lower the cab. Refer to Cab Tilting in General
Information.
23. Remove each center pin by tapping with a
hammer, while lowering the cab slowly.
215795
Notice: If the lifting straps encompass the door

frames, the window run channels may be damaged.
24. Perform the following procedure in order to
remove the cab from the chassis. Keep in mind
that the trimmed cab weighs about 1,000 Ibs.
24.1. Use four commercial straps that are
6 inches wide and about 10 feet long in
order to lift the cab from the chassis.
24.2. Pass the straps into the cab through the
door on each side at the top rear of the
window openings.
24.3. Connect the straps in the center.
24.4. Close the doors.
25. Walk around the cab in order to make sure all
components have been disconnected from the
chassis.
26. Raise the cab slowly. Use the aid of a helper in
order to guide the cab while the cab is being
215784 lifted.
1998 -
MD-lsuzu
1. Block the chassis wheels.
Notice: If the lifting straps encompass the door

frames, the window run channels may be
damaged.
2. Perform the following procedure in order to
install the cab onto the chassis. Keep in mind

window openings.
215784
3. Apply grease to the following areas of the cab

mounts:
.
The circumference area of the bracket where
the washer comes in contact
The bushing inner surface in the side where
the sleeve is inserted
At least two areas on both inside surfaces of
the bracket where the washer comes in
contact
215820
4. Install the left and the right center pins.

5. Perform the following procedure:
5.1. Hook a wire to the cab striker.
5.2. Pull the safety lever.
5.3. Tilt the cab slowly.
5.4. Use the wire in order to keep the cab
from floating up.
and Notices.
6. Extend the cab support and lock it into position.
Tighten
215795
7998 -
MD-lsuzu
7. Perform the following in order to install the

torsion bar levers.
.
Locate the left and right identification marks
before installation.
Match the serration.
Install the torsion bar levers.
Tighten
Tighten the bolt/nut to 37 N.m (27 Ib ft).
8. Use the match marks made during disassembly

as a guide in order to apply grease to the
steering shaft.
9. Insert the steering shaft and the steering unit

securely to the far end.
10. Tighten the key bolt.
Tighten
11. Connect the throttle cable.
12. Connect the transmission cables.
13. Connect the air brake hoses (if equipped) or
the linkage to the brake master cylinder.
14. Connect the parking brake cable.
15. Lower the cab.
16. Install the clutch fluid pipe (if equipped).
17. Install the main wire harness under the hood.
18. Install the ground strap.
20. Install the left and the right headlamp
assemblies.
21. Install the grille.
23. Recharge the air conditioning refrigerant to
specification.
24. Refill the engine coolant to proper level.
25. Bleed the clutch system.
Cab Lock Replacement
Removal Procedure
1. Remove the cushion rubber.
2. Remove the connecting rod.
3. Remove the safety rod.
4. Remove the return spring.
215775
1998 -
MD-lsuzu
5. Remove the hand lever assembly.
215777
6. Remove the safety lock assembly.

7. Remove the safety lock hook.
8. Remove the safety lock bracket.
215779
9. Remove the cab lock assembly.

10. Remove the return spring.
11. Remove the rebound rubber plate.
12. Remove the rebound rubber.
13. Remove the rebound rubber support.
14. Remove the cab lock hook.
15. Remove the link plate.
16. Remove the cab lock hook.
17. Remove the link plate.
18. Remove the cab lock bracket.
19. Remove the rear cab mount bracket.
20. Inspect the rebound rubber for any cracks or
damage.
215775
1998 -
MD-lsuzu
Notices.
1. Install the rear cab mount bracket.

Tighten
2. Install the cab lock bracket.
3. Install the link plate.
4. Apply grease to the pin of the bracket.
5. Install the cab lock hook.
6. Apply grease to the support.
7. Install the rebound rubber support.
8. Install the rebound rubber.
9. Install the rebound rubber plate.
10. Install the return spring.
11. Install the cab lock assembly.
Tighten
215775 Tighten the bolts to 40 N.m (30 Ib ft).
12. Install the safety lock bracket.

13. Apply grease to the hook.
14. Install the safety lock hook.
15. Install the safety lock assembly.
215779
16. Install the hand lever assembly.

17. Install the return spring.
18. Apply grease to the safety rod.
19. Install the safety rod.
20. Install the connecting rod.
21. Install the cushion rubber.
22. Adjust the hook so that the hook rests in the
center of the mounting point when latched.
1998 -
MD-lsuzu
Cab Tilt Support Replacement

Removal Procedure
1. Raise the cab and support. Refer to Cab Tilting
in General Information.

3. Securely fasten a rope to the cab lock.
In order to keep the cab tilted, use a hoist or
chain block.
4. Remove the following items:
The pin

The washer

The cotter pin
5. Remove the lower bracket.
215680
1. Connect the cab tilt support to the cab.
215679
1998 -
MD-lsuzu
192 Body Front End Body and Accessories

Notices.
2. Install the lower bracket.

Tighten
Tighten the bolt to 45 N.m (33 Ib ft).
3. Lower the cab until the hole in the cab support

inner channel aligns with the top hole in the
cab support outer channel.
215680
4. Install the following items: pin, washer, and

cotter pin.
The pin

The washer
The cotter pin
Step and Support Replacement -

Upper
Removal Procedure
Information.
2. Remove the upper step.
215693
7998 -
MD-lsuzu
3. Remove the upper step supports.
Notices.
1. Install the upper step supports.

Tighten
Tighten the bolt to 9 N.m (80 Ib in).
2. Install the upper step.

Tighten
Tighten the nut to 23 N.m (17 Ib ft).
215693
1998 -
MD-tsuzu
Fender Extension Bracket

Replacement Front
-
Removal Procedure
1. Disconnect the fender extension to the
bracket bolts.
2. Remove the fender extension.
3. Remove the fender extension brace.
215675
4. Remove the fender extension bracket.
223322
1. Install the fender extension bracket.
and Notices.
2. Install the fender extension brace.
Tighten
223322
7998 -
MD-ISUZU
3. Install the fender extension.

4. Connect the fender extension to the
bracket bolts.
Tighten
215675
Air Scoop Replacement

Removal Procedure
1. Loosen the upper connector clamp.
2. Remove the mounting nuts and bolts.
3. Remove the air scoop assembly.
215772
1. Install the air scoop assembly to the cab.
2. Install the mounting nuts and bolts.

3. Tighten the upper connector clamp.
215772
1998 -
MO-lsuzu
Panel Replacement -
Front Side
Removal Procedure
1. Raise the hood.
2. Open the door(s).
3. Remove the side panel screws.
4. Remove the side panel.
1. Install the side panel into the position.
2. Install the side panel screws.
3. Close the door(s).

4. Close the hood.
Splash Shield Replacement -

Condenser
Removal Procedure
1. Raise the cab. Refer to Cab Tilting in General
Information. Support the cab.
2. Remove the splash shield/reinforcement from
the inner fender panel.
1. Install the splash shield/reinforcement to the
inner fender panel.
Information.
215678
1998 -
MD-lsuzu
Wheelhouse Panel Replacement (Lower)

Removal Procedure.
1. Tilt and secure the cab. Refer to Cab Tilting in
2. Remove the inner extension panel bolts.
3. Remove the inner extension panel.
4. Remove the inner fender panel bolts.
5. Remove the inner fender panel.
215659
1. Install the inner fender panel to the cab.
and Notices.
2. Install the inner fender panel bolts.
Tighten
3. Install the inner extension panel.

4. Install the inner extension panel bolts.
Tighten
215659
1998 -
MD-lsuzu
Wheelhouse Panel Replacement (Upper)

Removal Procedure
Information.
2. Remove the upper inner fender panel bolts.
3. Remove the upper inner fender panel.
215664
1. Install the upper inner fender to the cab.

and Notices.
2. Install upper inner fender bolts.
Tighten
215664
1998 -
MD-lsuzu
Body and Accessories Doors 8-399
Doors
Specifications

Specification
Mirror Brace Nut 31 N.m 23lbft

Mirror Mounting Nut 13N.m 115lbin
Power Door Systems Schematic References

Subsection Name
Ground Disthbution Cell 14 8Wiring Systems
Interior Lights Dimming Cell 117 8Lighting Systems
1998 -
MD-lsuzu
8-400 Doors Body and Accessories
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?998 -
MD-lsuzu
00
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4 III
1998 -
MD-lsuzu
Component Locator
Power Door Systems Components

Power Door Systems Power Door Systems
Heated Mirror Switch On the center of the IP Component Views Connector End Views
in Doors in Doors
Heated Outside Power Door Systems

Rearview Mirror, On the left door exterior Component Views
Left Side in Doors
Heated Outside Power Door Systems

Rearview Mirror, On the right door exterior Component Views
Right Side in Doors
Heated/Lighted Mirror,
Power Door Systems
On the left door exterior Component Views
Left Side
in Doors
Heated/Lighted Mirror, Power Door Systems

On the right door exterior Component Views
Right Side
in Doors
Power Door Systems

Power Window Motor, Inside the right door, at the window

Connector End Views
Right Side regulator in Doors
Power Door Systems
On the right top of the I/P, under the
Power Window Relay Component Views
access panel, in the relay center 1 in Doors
Power Door Systems

Power Window Switch,
On the top of the left door panel
Connector End Views
Driver's Right Side
in Doors
Power Window Switch,

On the top of the right door panel
Right Side
Power Window Switch, Power Door Systems

In the right door harness to the power
Right Side C1
Connector End Views
(6 Cavities) window switch
in Doors
Power Window Switch, Power Door Systems

In the right door harness to the power
Right Side C2
Connector End Views
window switch
(8 Cavities) in Doors
1998 -
MD-lsuzu
Power Door Systems Component Views

Instrument Panel Switches, Center Forward View
231678
Legend
(1) Exhaust Brake Switch (5) Air Suspension Dump Switch
(2) Fast Idle Switch (6) Differential Lock Switch
(3) Heated Mirror Switch (7) Clearance Lamps Switch
(4) Two Speed Rear Axle Shift Switch
1998 -
MD-ISUZU
Mirror (Right)
231453
Legend
(1) Right Lighted Mirror (Heated Mirror similar)
1998 -
MD-lsuzu
Instrument Panel, Right Side Forward View
228475
Legend
(1) Relay Center 1 (2) IP Fuse Block
1998 -
MD-lsuzu
Power Door Systems Connector Power Window Motor (RH)

End Views
Heated Mirror Switch
2
f^\
6 1
n
^
^PB)):
435
237309
2 Way
Connector Part

Information
Female
237080
Circuit
6 Way
Connector Part

Information
Female power Window Motor
Power
A WHT 6
Circuit Feed L
UpP
BLU power Window Motor
Power
B
R Rill 5
^
1 PNK 141 Fuse 0 )utput Ignition
Output FeedD
Feed Down
own
2 ORN 142 Switch Output
Driverss Right Hand
Power Window Switch, Drivers
3 ORN 143 Switch Telltale Feed
4 BLK 144 Ground
Interior Lamps
P n
n
6 BLK/RED 146
Dimmin g Bus
Dimming
r-i r-i
1 2
= m
Lighted Mirror Jumper C216
3 4 5 6
LJ LJ LJ LJ
n fF^\ n
2 6 1
236719
6 Way
4 3 5 Connector Part
Information
Female
Circuit
1-2
Not Used
246499 3 LT GRN/BLK 10 Power Window Motor

Feed Up
Connector Part
6 Way F (BLK) LT
Information 4 9
Power Window Motor
GRN/RED Feed Down
Circuit
Pin Wire Color No. Function 5 ORN 7 Fuse Output
1 BRN 147 Illumination LT
6 8 Ground
GRN/WHT
2-4 Not Used
6
Not Used
1998 -
MD-lsuzu
Power Window Switch, RH (C1) Diagnostic Information and

Procedures
Power Windows System Check
1. Check condition of circuit breakers #6 and circuit
breaker #8. If circuit breaker is open, locate and
repair cause of overload. Replace circuit breaker as
necessary.
3. Check for mechanical failure or binding of power
windows.
4. Check condition or local circuit breaker in the RH
power window motor. The local circuit breaker will
reset automatically after cooling following an overload
236719
condition.
Connector Part 6 Way
Information
Female the insulation which could cause system malfunction
Circuit but prove good in a continuity/voltage check with a
Pin Wire Color No. Function system disconnected. These circuits may be
interrmittent or resistive when loaded, and if possible,
BLU
Power Window Motor should be checked by monitoring for a voltage drop
Feed Up with the system operational (under load).
Power Window Motor 6. Check for proper installation of aftermarket
WHT
Feed Down electronic equipment which may affect the integrity of
3-4 Not Used other systems. Refer to Checking Aftermarket
BRN Accessories.
Fuse Output
BLK Ground Heated Mirror System Check
1. Check condition of circuit breaker #22. If circuit
Power Window Switch, RH (C2) breaker is open, locate and repair cause of overload.
Replace circuit breaker if necessary.
3. Refer to Cell 117 (Interior Lamps-Dimming) to
diagnose heated mirror switch backlighting.
the insulation which could cause system malfunction
but prove good in a continuity/voltage check with a
system disconnected. These circuits may be
interrmittent or resistive when loaded, and if possible,
should be checked by monitoring for a voltage drop
with the system operational (under load).
5. Check for proper installation of aftermarket

electronic equipment which may affect the integrity of
236713 other systems. Refer to Checking Aftermarket
8 Way Accessories.
Connector Part
Information
Female
Circuit
7-10 Not Used
LT GRN/BLK
Power Window
11 10
Feed Down
LT
12 Power Window Feed Up
GRN/RED
LT Power Window Feed Up,
13
GRN/WHT Drivers
14 Not Used
1998 -
MD-lsuzu
Power Window Inoperative -

RF
1. Turn the ignition switch to run.
1 2. Backprobe the relay center No.1 with a test lamp
from relay 1 terminal 85 to ground.

1. Locate the open in CKT 439 (BRN) between the IP

fuse block and the relay center No. 1.
2
2. Repair the open in the circuit.

Backprobe relay center No.1 with a test lamp from the
3 relay 1 terminal 86 to B+.
1. Locate the open in CKT 438 (BLK) between the relay

center No.1 and G105.
4

Backprobe the relay center No. 1 with a test lamp from
5 relay 1 terminal 30 to ground.
1. Locate the open in CKT 440 (ORN/WHT) between

the IP fuse block and the relay center No.1.
6

Backprobe the relay center No.1 with a test lamp from
7 relay 1 terminal 87 to ground.

Replace relay 1.
8

Backprobe the right power window switch with a test lamp
9 from connector C1 terminal 5 to ground.
1. Locate the open in CKT 441 (ORN) between 6 the

relay center No.1 and the right power window switch.
10

Backprobe the right power window switch with a test lamp
11 from connector C1 terminal 6 to B+.
1. Locate the open CKT

in 69 (BLK)
4 and CKT
between the right power window switch and S348.
12

While pressing the right power window switch to the UP
position, backprobe the right power window switch with a
13
test lamp from connector C1 terminal 2 to ground.


Replace the right power window switch.
14

While pressing the right power window switch to the
DOWN position, backprobe right power window switch from
15
connector C1 terminal 2 to B+.

1998 -
MD-lsuzu
Power Window Inoperative -

RF (cont'd)
16

DOWN position, backprobe the right power window switch
17
with a test lamp from connector C1 terminal 1 to ground.

18


position, backprobe the right power window switch with a
19
test lamp from connector C1 terminal 1 to B+.


20

positon, backprobe the right power window motor with a
21
test lamp from terminal B to ground.
1. Locate the open in CKT

(WHT) between the
6
right power window switch and the right power
22 window motor.
in
2. Repair the open the circuit.

DOWN position, backprobe the right power window motor
23 with a test lamp from terminal A to ground.

1. Locate the open in CKT 5 (BLU) between the

right power window switch and the right power
24 window motor.

Does the test lamp light? System OK
Replace the power window motor.
25
Power Windows Inoperative From LF Switch

Definition: Right Power Window Motor Does Not Operate From Driver's Switch.
2. Backprobe the Right driver's power window switch

1 with a test lamp from terminal 5 to the chassis
ground.
Repair the open in CKT 443 (ORN) or CKT 3 (ORN)

between S 349 and the driver's Right side power window
2
switch.
Backprobe the driver's Right power window switch with a
3 test lamp from terminal 3 to B+.
1998 -
MD-lsuzu
Power Windows Inoperative From LF Switch (cont'd)

Inspect for an open in CKT 10 or CKT 447 (LT GRN/BLK)

between the driver's Right power window switch and the
4
right side power window switch.
Does an open exist in the circuits? Go to Step 5 Go to Step 6
Replace the Right power window switch.

5

Backprobe the driver's Right side power window switch
with a test lamp from terminal 6 to the chassis ground
6
while pressing switch.
Replace the driver's Right power window switch.

7
Backprobe the right side power window switch with a test

lamp from terminal 6 to B+ while pressing the switch in the
8
Down position.
Replace the driver's Right power window switch,
9

Backprobe the switch with a test lamp from terminal 4 to
B+ while keeping the switch operated in the Down
10
position.

11

Backprobe the switch with a test lamp from terminal 4 to
the chassis ground while keeping the switch operated in
12
the UP position.


13
Backprobe the switch with a test lamp from connector C 2

terminal 13 to the chassis ground while keeping the switch
14
operated in the Up position.

Repair the open in CKT 8 and CKT 445 (LT GRN/WHT)
between the driver's Right power window switch and the
15 Right side power window switch.

Backprobe the Right power window switch with a test lamp

from the connector terminal 12 to the chassis ground while
16
keeping the switch operated in the Down position.


Repair the open in CKT 9 or CKT 446 (LT GRN/RED).
17

Replace the Right power window switch.
18
1998
MD-lsuzu
Heated Mirrors Inoperative (Switch Indicator)

1 2. Backprobe the heated mirror switch with a test lamp

from terminal 1 to ground.

1. Press the heated mirror switch to the ON position.


Repair the open CKT 141, CKT 341, or CKT 415 (PNK),
in
3 between the IP fuse block and the heated mirror switch.
Does the heated mirror switch indicator operate? System OK

1. Locate the open in CKT 142 and CKT 342 (ORN)
between the heated mirror switch and S342.
4
2. Repair the open in CKT 142 and CKT 342 (ORN)

between the heated mirror switch and S 342.

Do the heated mirrors operate? System OK
1. Repair the open in CKT 142 and CKT 143 (ORN)

between the heated mirror switch terminal 2 to
5 terminal 3.
2. Replace the heated mirror switch.

Replace the heated mirror switch.
6
Does the heated mirror switch indicator operate? System OK Go to Step 8
Repair the open in CKT 144 (BLK), between the heated

7 mirror switch and splice pack No. 1.

8
Does the heated mirror switch indicator operate? System OK
Heated Mirrors Inoperative (Both Mirrors)

1. Turn the ignition switch to RUN position.

While pressing the heated mirror switch,backprobe the
2 switch with a test lamp from terminal 2 to ground.

Repair the open inCKT 141, CKT 341, or CKT 415 (PNK)
3 between the IP fuse block and the heated mirror switch.
Do the mirrors operate? System OK
Repair the CKT 142 (ORN) between the heated

open in
4 mirror switch and S342.

5
1998 -
MD-ISUZU
Heated Mirrors Inoperative (LH or RH Not Both)

2. Press the heated mirror switch to ON.

1
Backprobe the inoperative heated mirror with a test
3.
lamp from terminal A to ground.
Backprobe the inoperative heated mirror with a test lamp

2 from terminal B to B+.

Repair the open in CKT 342 or CKT 343 (ORN) between
3 S342 and the inoperative heated mirror.
Does the heated mirror operate? System OK
Replace the inoperative heated mirror.

4

Repair the open in CKT 33 (BLK) between the inoperative
5 heated mirror and G105.
Heated Mirrors Always On

1
2. Disconnect the heated mirror switch.

Did the heated mirrors turn off? Go to Step 3 Go to Step 2

Repair the short to voltage in CKT 142 (ORN) between the
heated mirror switch, the left side heated mirror, and the
2
right side heated mirror.

Did the heated mirrors turn off? System OK

3
Did the heated mirrors turn off? System OK
1998 -
MD-lsuzu
Repair Instructions
Door
Removal Procedure
Tools Required
J 38778 Trim Panel Retainer Tool
. J 9886-01 Regulator Handle Tool
1. Remove the window switch.

2. Remove the ash tray.
3. Remove the inside door handle. Refer to Door
Handle Replacement Inside.
-
4. Use the J 9886-01 in order to remove the

regulator handle left side only). Refer to
Window Handle Replacement.
5. Remove the inner glass and the seal (right side
only). Refer to Window Replacement -
214733
Inner Lower.
6. Use the J 38778 in order to remove the door

trim panel.
214730
1. Install the trim panel to the door.
2. Install the inner glass and the seal. Refer to

Window Replacement Inner Lower. -
3. Install the regulator handle. Refer to Window

Handle Replacement.
4. Install the inside door handle. Refer to Door
Handle Replacement Inside. -
5. Install the ash tray.
1998 -
MD-lsuzu
6. Install the window switch.
214733
Door Replacement
Removal Procedure
2. Disconnect the harness connectors.
3. Remove the front side panel(s).
4. Mark the location of the existing hinges on the
hinge pillar and the door.
5. Remove the bolts from the hinges. Instruct an

assistant to hold the door.
6. Remove the door from the vehicle.
1. Install the door to the vehicle.
2. Install the bolts to the hinges.

3. Install the front side panel(s).
4. Connect the harness connectors.
214741
1998 -
MD-lsuzu
Door Handle Replacement -

Outside
Removal Procedure
1. Remove the door trim panel. Refer to Trim
Panel Replacement -
Door.
2. Remove the water deflector.
3. Remove the lock rod from the handle.
4. Remove the left door handle.
214717
5. Remove the right door handle.
214716
7998 -
MD-ISUZU
16 Doors Body and Accessories
1. Install the left door handle.
214717
2. Install the right door handle.
214716
3. Install the lock rod to the handle.
7995 -
MD-lsuzu
4. Adjust the handle adjusting screw-to-lock

clearance to 1.0-3.0 mm (0.039-0.118 in). 1.0 -3.0 mm (0.039 -0.118")
5. Install the water deflector.
6. Install the trim panel. Refer to Trim Panel
Replacement Door. -
214712
Door Handle Replacement -

Inside
Removal Procedure
1.Remove the screw from the handle.
2. Disconnect the lock rods from the handle.
3. Remove the inner door handle.
214735
1. Install the inner door handle.
2. Connect the lock rods to the handle.

3. Install the screw to the handle.
214735
1998 -
MD-lsuzu
Lock Replacement -
Door
Removal Procedure
1. Remove the trim panel. Refer to Trim Panel
Replacement Door.
-

3. Remove the door window. Refer to Window
Replacement Door.
-
4. Remove the window regulator and the motor.

Refer to Window Regulator Replacement
(Left Side) or Window Regulator Replacement
(Right Side).
5. Remove the lock rods from the lock.
6. Remove the lock from the left door.
214717
7. Remove the lock from the right door.
7998 -
MD-lsuzu
1. Install the lock to the left door.
2. Install the lock to the right door.
3. Install the lock rods to the lock.

4. Install the window regulator. Refer to Window
Regulator Replacement (Left Side) or Window
Regulator Replacement (Right Side).
5. Install the door window. Refer to Window
Replacement -
Door.

Replacement -
Door.
214714
1998 -
MD-lsuzu
Lock Cylinder Replacement -

Door
Removal Procedure
Replacement Door. -

3. Remove the lock rod from the cylinder.
4. Remove the retaining clip from the cylinder.
1. Install the retaining clip to the cylinder.
2. Install the lock rod to the cylinder.

Replacement Door.-
214721
Striker Replacement -
Door
Removal Procedure
1. Mark the position of the striker on the
door pillar.
2. Remove the striker bolts.
3. Remove the striker from the door pillar.
214738
7995 -
MD-ISUZU
1. Install the striker to the door pillar.
2. Install the striker bolts.
214738
Window Regulator Replacement

(Right Side)
Removal Procedure
1. Remove the lower inner window. Refer to
Window Replacement
Inner Lower.
-

Replacement Door. -

Replacement Door. -
5. Remove the window regulator assembly.
1. Install the window regulator assembly.

Replacement Door.
-

Replacement Door. -
5. Install the lower inner window. Refer to Window

Replacement Inner Lower.
-
1998 -
MD-lsuzu
Window Regulator Replacement (Left Side)

Removal Procedure
Replacement Door. -

Replacement -
Door.
4. Remove the window regulator assembly.
1. Install the window regulator assembly.

Replacement Door.
-

Replacement -
Door.
214708
Window Handle Replacement

Removal Procedure
Tools Required
J 9886-01 Regulator Handle Tool
1. Remove the window regulator handle.

2. Insert the J 9886-01 between the handle and
ffiaaSi'i'*!"i*">l'lK*l^ffli
^^rf'?'**-^^;,*^ the bearing plate.
itâ^M1^"'""""^
i-iâsiiaa-^s";isaTO""ti';
-^::Y:<:^-:"^;-:"^-a1^-A-i^:;:.m^^^
;i"SKKK.:SSiâ:î!l;gi:a:^g::K:^B:Miigi^^^
3. Align the J 9886-01 parallel with the handle.
iiaia^ttBiilsBitMsiirt
^:^:^:::::':::^:::-::v:;:':::^::^ *::?:^w'^::^:Mlw:il'fc'rMwâ Push in the J 9886-01 in order to disengage
the clip.
4. Pull the handle from the door.
5. Remove the bearing plate.
J 9886-01
1. Install the bearing plate to the trim panel.
2. Install the window regulator handle.
3. Raise the window.

4. Push the clip onto the handle.
1998 -
MD-lsuzu
5. Insert the handle onto the regulator shaft.

Ensure that the handle is horizontal with the
knob pointing toward the front of the door.
6. Push the handle until the clip engages the
window regulator shaft.
Window Replacement -
Door
Removal Procedure
Replacement Door.
-

3. Remove the front run channel. Refer to Window
Run Channel Replacement.
4. Remove the rear run channel. Refer to Window
5. Remove the window from the window regulator
(left side).
6. Remove the window from the window regulator

(right side).
214706
1998 -
MD-lsuzu
1. Install the window to the window regulator
(left side).
2. Install the window to the window regulator

(right side).
3. Install the rear run channel. Refer to Window
4. Install the front run channel. Refer to Window
Replacement -
Door.
214706
Window Run Channel Replacement

Removal Procedure
Replacement Door.
-
2. Remove the water deflector.,

3. Remove the run channel(s) from the door.
214703
1998 -
MD-lsuzu
1. Install the run channel(s) to the door.

Replacement -
Door.
214703
Inner Lower
Removal Procedure
1. Open the window.
2. Remove the screws from the upper and the
lower hinges.
3. Remove the window seal.
1. Install the window seal.
2. Install the screws to the upper and the lower
hinges.
3. Close the window.
214734
1998 -
MD-lsuzu
Outer Lower
Removal Procedure
Tools Required
J 36020 Windshield Remover
Caution: If a window is cracked but still intact, it

should be crisscrossed with masking tape in
Injury.
1. Use the J 36020 in order to pass the wire
through the adhesive of the door glass toward
the inside of the cab.
2. Push and pull the wire alternately in order to
cut off the adhesive all around the glass.
Do not damage the locating pins or the
retaining pins.
3. Clean the door and the glass mating surfaces.
214724
1. Apply primer to the glass and the door panel
as shown to the areas indicated.
Allow the primer to dry for at least 3 minutes.
2. Install the molding to the outer glass.
3. Apply adhesive to the glass and the molding as
shown to the areas indicated.
Ensure that the adhesive is an even and
continuous bead.
214726
4. Install the glass to the door panel.
214724
1998 -
MD-lsuzu
Mirror Replacement
Removal Procedure
1. Disconnect the electrical connector, if equipped
a lighted or a heated mirror.
with
2. Remove the two nuts (1) holding the mirror

brace (2) to the door.
3. Remove the mirror assembly (2) or the lighted

or the heated mirror assembly (1), if equipped.
4. Remove the spot mirror (3), if equipped.
214696
7998 -
MD-lsuzu
1. Install the spot mirror (3), if equipped.
2. Install the mirror assembly (2) or the lighted or

the heated mirror assembly (1), if equipped, to
the door.
214696
3. Install the two mounting nuts (1) to the

brace (2).
4. Connect the electrical connector, if equipped
with a lighted or a heated mirror.
214701
1998 -
MD-lsuzu
Description and Operation The operation of the driver's right hand power
window switch is similar to the right power window
Power Windows Circuit Description switch with the exception that the motor and ground
With the ignition switch in either the RUN or START leads of this switch are connected to the motor and
position, the voltage is applied to both the power
G205 through the right hand power window switch.
In all other ways the operation of the switches are
window switch through the closed contacts of relay
the same.
When you press the right hand power window switch
to the UP position, voltage is applied to one side of Heated Mirror Circuit Description
the motor through the now closed UP contacts of the
Voltage is applied through circuit breaker No. 22 to
switch, and the other side of the motor connects to
G105 through the now closed DOWN contacts of the the heated mirror switch when the ignition switch is
in RUN position. When the switch is pressed, the
switch. This causes the motor to turn and raise the
switch closes, allowing voltage to be applied to the
window. When the switch is released, the contacts
left side heated mirror, the right side heated mirror,
return to their neutral state and nothing happens.
When you press the right hand power window switch and the heated mirror switch indicator. Since both of
the heated mirrors are separately permanently
to the down position, voltage is now applied to one
side of the motor through the now closed DOWN grounded at G105, the heater element begins to
contact and the other side of the motor is connected warm. Since the indicator is permanently grounded
through the joint connector No.1, the indicator will
to G105 through the now closed UP contact. This
light. The heaters and indicator will remain energized
causes the motor to turn in the opposite direction until either the ignition switch is turned out of the
which causes the window to go down.
RUN position or the heated mirror switch is moved
to the OFF position.
1998 -
MD-lsuzu
J 9886-01
Regulator Handle Tool
255345
J 36020
Windshield Remover
204460
1998 -
MD-lsuzu
Seats
Specifications

Specification
Brake Control Module Bolt 2.5 N.m 22 Ib in
Center Seat Bolt 15N.m 12lbft

Center Seat Nut 15 N.m 12lbft
Driver or Passenger Seat Nut 15N.m 12lbft
Seat Riser Bolt 8 N.m 71 Ib in
Seat Riser Cover Bolt 8 N.m 71 Ib in
Seat Riser Nut 31 N.m 23lbft

Speedo Adapter Assembly Bolt 2.5 N.m 22 Ib in
Seat -
Manual Adjuster Does Not Unlock
Problem Action
The locking wire is too loose. Tighten the locking wire.
The locking wire is disconnected or Repair or replace the locking wire.

broken.
The adjuster lock bar is sticking or Lubricate the lock bar pivot.
binding.
Seat -
Manual Adjuster Between Lock Positions
Problem Action
Adjusters misaligned. Align the adjusters.
Adjusters new, not broken in. Operate the seat to the fully forward and fully rearward positions several times in
order to work the tightness out of the channels.
Adjuster(s) improperly lubricated. Lubricate the adjuster channels.
Adjuster(s) bent or damaged. Replace the adjuster(s).
Adjusters binding or damaged. Lubricate or replace the adjusters.
Seat components loose, damaged, Repair or replace the seat.

or broken.
Seat mounting bolts loose. Tighten the mounting bolts to specifications. Refer to Fastener Tightening
Specifications.
Seat -
Manual Adjuster Does Not Lock
Problem Action
Locking wire too tight. Loosen the locking wire.
Adjuster lock bar spring disconnected Repair or replace the spring.
or broken.
Adjuster lock bar sticking or binding. Lubricate the lock bar pivot or replace the adjuster.
1998 -
MD-lsuzu
Repair Instructions
Seat Replacement
Removal Procedure
1. Remove the seat nuts.
2. Remove the seat.
1. Install the seat.

and Notices.
2. Install the driver or passenger seat nuts.
Tighten
Tighten the driver or passenger seat nuts to
15N.m (12 Ib ft).
1998 -
MD-lsuzu
Body and Accessories Seats 8-433
Seat Replacement -
Center
Removal Procedure
1. Tilt the cab forward. Refer to Cab Tilting in
3. Lower the cab.
4. Lift the floor covering upward.
5. Remove the seat bolts (1).
6. Remove the center seat (2).
214537
1. Install the center seat (2).

and Notices.
2. Install the seat bolts (1).
3. Tilt the cab forward.
4. Install the seat nuts.
Information.
Tighten
Tighten the center seat nuts to 15 N.m
(12lbft).
. Tighten the seat bolts to 15 N.m (12 Ib ft).
214537
1998 -
MD-lsuzu
Seat Riser Replacement (Passenger)

Removal Procedure
2. Remove the passenger seat.
214531
3. Remove the speedo adapter bolts.
214546
1998 -
MD-lsuzu
4. Remove the riser cover bolts.

5. Remove the riser cover.
214550
6. Remove the brake control module bracket bolts.

7. Remove the brake control module bracket.
214553
8. Remove the mount bracket assembly bolts.

9. Carefully slide the mount bracket assembly
forward.
11. Remove the riser nuts.
13. Remove the riser bolts.
214554
1998 -
MO-lsuzu
136 Seats Body and Accessories
14. Remove the riser.
1. Install the riser.

and Notices.
2. Install the riser bolts.
3. Install the riser nuts.

Tighten
Tighten the riser bolts to 31 N.m (23 Ib ft).
Tighten the riser nuts to 31 N.m (23 Ib ft).
214542
4. Carefully slide the mount bracket assembly

rearward.
5. Install the mount bracket assembly bolts.
Tighten
Tighten the mount bracket assembly bolts to
2.5 N.m (22 Ib in).
214554
1998 -
MD-ISUZU
6. Install the brake control module bracket in the

vehicle.
7. Install the brake control module bracket bolts.
Tighten
Tighten the brake control module bracket bolts
to 2.5 N.m (22 Ib in).
214553
8. Install the riser cover.
2t4550
9. Install the speedo adapter bolts.

Tighten
Tighten the speedo adapter bolts to 2.5 N.m
(22 Ib in).
10. Install the riser cover bolts.
Tighten
Tighten the riser cover bolts to 8 N.m (71 Ib in).
214546
1999 -
MD-lsuzu
-438 Seats Body and Accessories
11. Install the seat.
Tighten
Tighten the seat nuts to 15 N.m (12 Ib ft).
214531
Seat Riser Replacement (Driver)

Removal Procedure
2. Remove the driver seat.
214531
1998 -
MD-lsuzu
3. Remove the riser cover bolts (4).

4. Remove the riser cover (3).
6. Remove the riser nuts.
8. Remove the riser bolts.
9. Remove the riser (2).
214540
1. Install the riser.

and Notices.
2. Install the riser bolts.
3. Install the riser nuts.
Tighten
. Tighten the riser bolts to 31 N.m (23 Ib ft).
Tighten the riser nuts to 31 N.m (23 Ib ft).
214531
1998 -
MD-lsuzu
8-440 Seats Body and Accessories
4. Install the riser cover (3).

5. Install the riser cover bolts (4).
Tighten
Tighten the riser cover bolts to 8 N.m (71 Ib in).
6. Install the driver seat (1).

Tighten
Tighten the seat nuts to 15 N.m (12 Ib ft).
214540
1998 -
MD-lsuzu
Body and Accessories Interior Trim 8-441
Interior Trim
Repair Instructions
Mat/Carpet Replacement -
Front Floor
Removal Procedure
1. Remove the seats. Refer to Seat Replacement
in Seats.
2. Remove the door sill trim plates. Refer to Door

Sill Plate Replacement.
3. Remove the transmission control trim.

4. Remove the mat (1) from the floor.
1. Install the mat (1) to the floor.
2. Install the transmission control trim.

3. Install the door sill trim plates. Refer to Door
Sill Plate Replacement.
4. Install the seats. Refer to Seat Replacement

in Seats.
214648
1998 -
MD-ISUZU
42 Interior Trim Body and Accessories
Cargo Area Rear

Removal Procedure
1. Remove the rear curtain rail.
2. Remove the rear window upper molding. Refer
to Rear Window Replacement in Stationary
Windows.
3. Remove the retaining screws.
4. Remove the rear panel molding (1) by pulling it
away from the rear window sealing strip.
1. Using a flat bladed tool, carefully position the
rear panel molding (1) around the window glass
under the sealing strip.
2. Install the retaining screws.
3. Install the rear window upper molding. Refer to
Rear Window Replacement in Stationary
Windows.
4. Install the rear curtain rail.
214634
Door Sill Plate Replacement

Removal Procedure
1. Remove the four door sill trim plate screws.
2. Remove the door sill trim plate.
206138
1998 -
MD-ISUZU
1. Install the door sill trim plate.
2. Install the four door sill trim plate screws.
206138
Headliner Replacement
Removal Procedure
1. Remove the overhead storage compartment.
Refer to Console Replacement Overhead. -
2. Remove the side molding from above both

doors. Refer to Garnish Molding Replacement -
Side Door Upper (On Roof Panel) or Garnish

Molding Replacement Side Door Upper
-
(On Body).
3. Remove the rear window upper molding. Refer
to Molding Replacement Rear Window Upper.
-
4. Remove the front curtain rail screws.

5. Remove the headliner assembly (1) by carefully
pulling the headliner down to release the
retaining clips.
1. Install the headliner assembly (1).
2. Install the front curtain rail screws.

3. Install the rear window upper molding. Refer to
Molding Replacement Rear Window Upper.
-
4. Install the side molding above both doors. Refer

to Garnish Molding Replacement Side Door
-
Upper (On Roof Panel) or Garnish Molding

Replacement Side Door Upper (On Body).
-
5. Install the overhead storage compartments.

Refer to Console Replacement Overhead. -
214644
1998 -
MD-lsuzu
Console Replacement -
Overhead
Removal Procedure
1. Remove the sunshade(s) (1).
207691
2. Remove the two retainers from in front of the

dome lamp by twisting them counterclockwise.
3. Remove the dome lamp assembly.
4. Remove the center trim by carefully pulling the
center trim back to release the retainers.
214638
5. Remove the retaining screws (3) from the

storage compartment(s) (1).
6. Remove the storage compartment(s) from the
roof panel.
214640
7995 -
MD-lsuzu
1. Install the storage compartment(s) (1) to the
roof panel.
2. Install the storage compartment retaining
screws (3).
3. Install the center trim by pushing the center trim
into position.
214640
4. Install the dome lamp assembly (1).

5. Install the two dome lamp trim retainers.
214638
6. Install the sunshade(s) (1).
207691
1998 -
MD-lsuzu
Sunshade Replacement
Removal Procedure
1. Remove the sunshade screws (2).
2. Remove the sunshade (1).
207691
1. Install the sunshade to the vehicle (1).
2. Install the sunshade screws (2).
207691
Windshield Pillar
Removal Procedure
1. Remove the assist handle, if equipped.
2. Pull down on the door opening sealing strip in
order to reveal the garnish molding.
3. Remove the garnish molding.
7998 -
MD-lsuzu
1. Install the garnish molding.
2. Install the door opening sealing strip.
3. Install the assist handle, if equipped.
215173

Side Door
Upper (On Roof Panel)
Removal Procedure
1.Remove the rear upper trim panels.
2. Remove the assist handle, if equipped.
3. Pull the side molding outward in order to
release the retaining clips.
1. Push the side molding into position.
2. Install the assist handle, if equipped..
3. Install the rear trim panel.

Side Door
Upper (On Body)
Removal Procedure
1. Remove the curtain rails.
2. Pull down on the door opening sealing strip.
3. In order to release the adhesive, remove the
side molding by carefully pulling the side
molding away.
215173
1998 -
MD-lsuzu
8-448 Interior Trim Body and Accessories
1. Apply adhesive to the side molding, as
necessary.
2. Push the molding into position against the body
of the vehicle.
3. Install the door opening sealing strip.

4. Install the curtain rails.
215173
Molding Replacement -
Rear Window Upper

Removal Procedure
1. Remove the screws from the rear trim panels.
2. Pull the rear window upper molding forward to
release the retaining clips.
1. Align the retaining clips with the holes in the
roof panel and push the upper molding into
position.
2. Install the lower retaining screws.
1998 -
MD-lsuzu

Rear Quarter
Removal Procedure
1. Remove the door opening sealing strip.
2. Remove the upper seat belt bolt.
4. Remove the molding retainers.
5. Remove the quarter window side molding (1)
by pulling the molding from around the
quarter glass.
214636
1. Using a flat-bladed tool, carefully install the
molding (1) around the quarter glass under the
sealing strip.
2. Install the molding retainers.

4. Install the upper seat belt bolt.
214636
1998 -
MD-ISUZU
Cleaning Vinyl Trim Cleaning Agents

You can usually remove soilage from vinyl using Caution: Follow the manufacturer's advice when
warm water and mild soap. cleaning agents or other chemicals are used
1. Apply a small amount of soap solution. inside or outside of the vehicle. Some cleaners
few minutes in order may be poisonous or flammable. Improper use
2. Let the solution soak for a
to loosen the dirt. may cause personal Injury, paint to peel, or

damage to components. When cleaning the
3. Rub briskly with a clean, damp cloth in order to interior or exterior of the vehicle, do not use the
remove dirt and traces of soap. If needed, you following cleaners except as specifically directed
may repeat this several times. In the fabric cleaning procedures contained in
Soilage from tars, asphalt, shoe polish or the like will this manual:
stain if left on the trim.
Acetone
. Wipe off these compounds as quickly as
Alcohols
possible.

Allphatic hydrocarbons
.
Clean the area using a clean cloth dampened
with Vinyl/Leather Cleaner (solvent type).

Aromatic hydrocarbons

Bleaches
Spot Cleaning Fabric Trim
Enamel reducers
Before trying to remove a spot or a stain from the
Esters
fabric, determine the type and the age of the spot or
stain. Water or a mild soap solution is sufficient to

Ethylene chloride
remove stains of some types. Remove spots or
Ketones
stains as soon as possible.
Lacquer thinners
Some soils or stains, such as lipstick, inks, and
Laundry soaps
grease are very difficult, and sometimes impossible,
to remove completely.

Methylene chloride
Nail polish removers
When cleaning this type of stain, do not enlarge the
soiled area. Use a solvent type fabric cleaner in
Napthas
order to spot clean grease, oil, or fat stains.
Penetrating oils
1. Gently scrape any excess stain from the trim
Plastlclzers
material. Use a small amount of cleaner, light
Propylene glycols
pressure, and clean cloths (preferably
cheesecloth) when spot cleaning.

Reducing agents

Silicones
2. Start cleaning at the outside of the stain and
feather towards the center. Frequently change
Tetrachloroethane
to a clean section of the cloth. Never use carbon tetrachloride, gasoline,
3. After the stain has been removed, dry the area benzene, or naphtha for any cleaning purpose.
immediately with a heat dryer or a heat lamp to Some after market products used to increase the
help prevent a cleaning ring. Use caution when gloss of the instrument panel contain some of
employing a heat dryer or lamp to avoid the products listed above. It Is Important to only
damaging the fabric. use those solutions recommeded for cleaning the
4. If a cleaning ring forms, immediately repeat the identified surfaces. As a general rule, the
cleaning operation over a slightly larger area of following guidelines must be used:
cloth with emphasis on feathering toward the 1. Vinyl and Non-painted plastic -
Use vinyl
stain's center. and plastic cleaners.
5. If a ring still remains, mask off the surrounding 2. Rubber -
Use rubber cleaners.
trim sections. Clean the entire area using
3. Painted Plastic Surfaces Use only mild

multi-purpose powered cleaner.

detergents.
Open all vehicle doors for ventilation when any
cleaning agents or other chemicals are used
inside of the vehicle. Overexposure to some
vapors, which is more likely to occur In small,
unventilated spaces, may result in a health
problem.
1998 -
MD-lsuzu
Notice: To avoid possible permanent discoloration of Use a non-abrasive cleaner on the outside of the
light colored seats, do not let materials with windshield. Clean the wiper blades using a cloth
non-color fast materials come in contact with seat soaked in a solution of one-half water and one-half
trim materials until totally dry. This includes certain Optikleen or equivalent. You may also use a
types of clothing, such as colored denims, corduroys, solution of one-half water and one-half methanol
leathers, and suedes. alcohol. Then rinse the blade with water.
Use the proper cleaning techniques and cleaners on
Removal of Specific Stains
the first cleaning in order to avoid the following types
of staining: Grease or Oily Stains

Water spots This cleaning procedure applies to stains caused by
Spot rings the following substances:
Setting of stains
Grease
These stains are more difficult to remove in a . Oil
second cleaning.
Butter or margarine
Remove any dust and loose dirt that collects on Shoe polish
interior fabrics through frequent vacuuming or the

Coffee with cream
use of a soft bristle brush.

Chewing gum
Wipe vinyl trim regularly using a clean damp cloth.

Cosmetic creams
Interior Cleaning
Vegetable oils
Use multi-purpose powered cleaner for cleaning
a
Wax crayon
fabric trim and for cleaning panel sections where .
Tar and asphalt
small cleaning rings may be left from spot cleaning.
1. Carefully scrape off the excess matter.

Vacuum and brush the area in order to remove
any loose dirt surrounding the trim along stitch 2. Use a solvent type fabric cleaner on the stained
or welt lines. area. Refer to Spot Cleaning Fabric Trim.

Clean the complete trim panel one section at 3. Shoe polish, wax crayons, tar, and asphalt will
a time. stain if left on the trim. Remove these stains as
soon as possible. Use care because the

When mixing the cleaner, follow the directions
cleaner may cause the stains to bleed as the
on the container label.
cleaner dissolves the stains.

Use suds on clean sponge.
a
Do not saturate the material or rub the material Non-Greasy Stains

harshly. These stains include the following substances:

Wipe off any remaining residue using a slightly
Ketchup
damp absorbent towel or cloth. Black coffee
.
You may use heat dryer or heat lamp to dry
a Egg
the area. Use caution with a heat dryer or lamp Fruit
to prevent fabric damage.
Fruit juice
Basic Steps Before Cleaning . Milk

Remove stains as quickly as possible before Soft drinks
the stains set.
Wine

Use a clean cloth or sponge. Frequently . Vomit
change to a clean section of the cloth. Use a
Blood
soft brush if stains persist.
.
.
Use solvent-type cleaners in a well ventilated

Urine
area. Do not saturate the stained area. 1. Carefully scrape off the excess matter.
If a ring forms after spot cleaning, immediately 2. Sponge the stain with cool water.
clean the entire area. 3. If a stain remains, use a foam type
. Follow the manufacturer's instructions for all multi-purpose powered cleaner to remove the
cleaning agents. stain. Refer to Interior Cleaning.
4. If an odor lingers after cleaning vomit or urine,
Cleaning Glass Surfaces treat the area using a water/baking soda
Clean glass surfaces on a regular basis. Use a solution of 5 milliliters (1 teaspoon) baking soda
glass cleaner to remove normal tobacco smoke and to 250 milliliters (1 cup) of lukewarm water.
dust films.
5. Finally, if needed, clean lightly using a solvent
type fabric cleaner.
99fl -
MD-teuzu
Combination Stains Seat Belt Care

These stains include the following substances: Caution: Do not bleach seat belts. Do not dye

Candy seat belts. This may severely weaken the seat
Ice cream belts. Damaged seat belts are a safety hazard.
Keep the seat belts clean and dry.

Mayonnaise
Chili sauce
Clean the seat belts only with mild soap and
lukewarm water.
Stains of unknown origin
1. Carefully scrape off the excess matter.
2. Clean with cold water.
3. Allow the area to dry.
4. If a stain remains, clean the stain using a
solvent type fabric cleaner.
1998 -
MD-lsuzu
Body and Panel Information and Repair 8-453
Accessories_____________Plastic
Plastic Panel Information and Repair
Repair Instructions
Flexible Plastic Part Refinishing
Notice: Use supplies, primers, basecoats and
clearcoats from the same manufacturer. Do not
intermix paint systems or paint damage may occur.
Follow the paint manufacturer's instructions regarding

preparation, priming and refinishing when working
with flexible plastic parts. These parts may require
special additives in the primers and topcoat in order
to prevent cracking and poor adhesion. Use the
manufacturer's recommended materials. Do not
intermix with other paint systems.
The Service Parts Identification Label contains all the
information necessary regarding paint technology,
paint codes and trim level, in order to identify the
correct paint. Refer to Label -
Service Parts ID in
1998 -
MO-ISUZU
8-454 Plastic Panel Information and Body and Accessories
Repair___________
BLANK
1998 -
MD-lsuzu
Body and Accessories Paint/Coatings 8-455
Paint/Coatings
Specifications
Clearcoat Repair Specifications -

3M Products
Dual Action Orbital Hand Glazing/
Paint Condition Wet Sanding Compounding Rotary Polisher Polisher Polishing
Perfect-It Polishing
Pad Glaze
P/N 05995/05996
New car prep Perfect-It Foam Premium Liquid/Paste
or fine
Polishing Pad Waxes
wheel marks P/N 05776 P/N 0654/06055
Hookit DA 6 inch
Backup Pad
P/N 05776
Perfect-It Polishing Perfect-It Polishing

Pad Glaze Pad Glaze
Perfect-It Hand Glaze
P/N 05995/05996 P/N 05995/05996
P/N 05997
Swirl marks, Perfect-It Foam Perfect-It Foam
or
water spottting,
Polishing Pad Polishing Pad
or light oxidation P/N 05776 P/N 05725 Premium Liquid/Paste
Waxes
Hookit SBS/Perfect-lt Hookit DA 6 inch
P/N 0654/06055
Backup Pad Backup Pad
P/N 05717/18 P/N 05776

Pad Glaze Pad Glaze
Perfect-It 11 Rubbing Perfect-It Hand Glaze
P/N 05995/05996 P/N 05995/05996
Comp. pad
P/N 05997
Overspray or P/N 059723 Perfect-It Foam Perfect-It Foam
or
medium
Perfect-It 11 Foam P/N 05776 P/N 05776 Premium Liquid/Paste
oxidation
Comp. Pad Waxes
P/N 05723 P/N 0654/06055
P/N 05717/18 P/N 05776

Pad Glaze Pad Glaze
Perfect-It Hand Glaze
P/N 05995/05996 P/N 05995/05996
Perfect-It 11 Rubbing P/N 05997
Heavy oxidation Comp. pad Perfect-It Foam Perfect-It Foam
or
or minor acid Micro Fine 2000 P/N 059723 Polishing Pad Polishing Pad
rain pitting P/N 05776 P/N 05776 Premium Liquid/Paste
Perfect-It 11 Foam
\A/flypc
VVC1ACO
Comp. Pad Hookit SBS/Perfect-lt Hookit DA 6 inch
P/N 0654/06055
P/N 05723 Backup Pad Backup Pad
P/N 05717/18 P/N 05776
1998 -
MD-lsuzu
8-456 Paint/Coatings Body and Accessories

3M Products (cont'd)
Dual Action Orbital Hand Glazing/
Paint Condition Wet Sanding Compounding Rotary Polisher Polisher Polishing
Pad Glaze Pad Glaze
P/N 05995/05996 P/N 05995/05996
P/N 05997
Dust nibs, minor Comp. pad
Perfect-It Foam Perfect-It Foam
scratches, or Micro Fine 1500 P/N 059723 or
major acid rain or 2000 Perfect-It 11 Foam P/N 05776 Premium Liquid/Paste
P/N 05776
pitting Comp. Pad Waxes
Hookit SBS/Perfect-lt Perfect-It Foam
P/N 05723 P/N 0654/06055
Backup Pad Polishing Pad
P/N 05717/18 P/N 05776
Pad Glaze Pad Glaze
P/N 05995/05996 P/N 05995/05996
P/N 05997
Comp. pad
Orange peel, Perfect-It Foam Perfect-It Foam
Micro fine 1200 P/N 059723 or
paint runs or Polishing Pad Polishing Pad
or 1500 Perfect-It 11 Foam P/N 05776 P/N 05776 Premium Liquid/Paste
sags
Comp. Pad \A/aYOC
VVdACO
P/N 05723 P/N 0654/06055
P/N 05717/18 P/N 05776

Meguiar Products
Paint Condition Wet Sanding Cleaning Polishing
New car prep or fine wheel Swirl Free Polish (M-82)

marks W-6000 Pad for DA polishers

Swirl marks, chemical spotting Swirl Free Polish (No. 9)

or light oxidation W-9000 Finishing Pad

Overspray or medium
Heavy-Cut Cleaner (No. 4) Swirl Remover (M-82) W-9000
oxidation W-7000 Cutting Pad Finishing Pad
Heavy oxidation or minor acid

Compound Power Cleaner Swirl Free Polish (M-82)
rain pitting (M-84) W-7000 Cutting Pad W-6000 Finishing Pad
2000 Grade Unigrit Compound Power Cleaner Swirl Free Polish (M-2)
Dust nibs
Sanding Block (M-84) W-7000 Cutting Pad W-9000 Finishing Pad
Minor scratches or acid rain 2000 Grade Unigrit Compound Power Cleaner Swirl Free Polish (M-2)
pitting Sanding Paper (M-84) W-7000 Cutting Pad W-9000 Finishing Pad
1500 Grade Unigrit Compound Power Cleaner wirl Free Polish (M-2) W-6000
Major runs or sags
Sanding Block (M-84) W-7000 Cutting Pad Pad for DA Polishers
Major orange peel or acid rain 1500 Grade Unigrit Compound Power Cleaner Swirl Free Polish (M-2)
pitting Sanding Paper (M-84) W-7000 Cutting Pad W-6000 Pad for DA Polishers
Quick Detailer (M-6601) will
provide protection without
streaking. Contains the
Need for protection
mildest of cleaners which will

insure even application of
polish.
1998 -
MD-lsuzu
Basecoat/Clearcoat Paint Systems Caution: Foam sound deadeners must be

removed from areas within 6 Inches of where
Caution: Exposure to isocyanates during paint
flame is to be used for body repairs. When
preparation and application processes can cause
reinstalling foam sound deadeners, avoid inhaling
severe breathing problems. Read and follow all of
fumes as bodily injury may result.
the instructions from the manufacturers of painting
materials, equipment, and protective gear. Caution: Approved safety glasses and gloves
should be worn when performing this procedure
Caution: Approved safety glasses and gloves
to reduce the chance of personal injury.
to reduce the chance of personal injury. Notice: The anti-theft label found on some major
body panels MUST be covered before performing
All paint finish repairs of rigid exterior surfaces, are
any painting, rustproofing or undercoating
to meet Isuzu standards. All approved products,
including Volatile Organic Compound (VOC) procedures. The mask must also be removed
following those procedures. Failure to follow these
-
compliant regulations are listed in the system

precautionary steps may result in liability for violation
approach recommended by the individual of the Federal Vehicle Theft Prevention Standard,
manufacture. Refer to the manufactures instructions and subject the vehicle owner to possible suspicion
for the detailed procedures for materials used in
that the part was stolen.
there paint system in the painting repairs of rigid
exterior surfaces. All components of an approved Anti-corrosion materials providing rust resistance are
paint system have been engineered to ensure proper used on interior and exterior surfaces of metal
adhesion between layers. panels. These materials include metals such as
Mixing paint systems or substituting a product of one one-sided and two-sided galvanized zinc, and
zinciron alloy steels. These treated metals are used
manufacture for another manufacture's product is not
on components such as fenders, doors, quarter
allowed. If incompatible products are used together
panels, rocker panels, lids, floor pans,
some problems listed can occur:
wheelhousings, and other critical parts.
Lifting of primer coats caused by overly
Metal conditioners and primers are used on interior
aggressive solvents in subsequent layers.
and exterior surfaces along with protective waxes on

Loss of adhesion between layers due to interior surfaces in areas where moisture might
incompatibility of resin systems.
accumulate. Sealers are applied along exposed joints

Solvent popping or pinholing due to and moisture-repelling asphaltic sound deadeners are
inappropriate solvent selection. applied inside the wheel wells, doors, and on some

Poor through-curing due to incompatible underbody components.
hardener resins or insufficient reactivity. Any procedure that disturbs these special treatments,

Gloss reduction due to incompatible resins such as panel replacement or collision damage
and/or solvents. repair operations, may leave the metal unprotected
and result in corrosion. Proper recoating of these
Gloss reduction due to incompatible resins
surfaces with service-type anti-corrosion material is
and/or solvents.
essential.

Poor color accuracy due to pigment interactions Metal conditioners and primer coatings are applied to
with incompatible resins and/or solvents. all metal panels at the time of vehicle manufacture.
. Film defects (craters, blisters, orange peel loss After repair and/or replacement parts are installed, all
of gloss) due to the use of inferior quality raw accessible bare metal surfaces must be treated with
materials in incompatible products. metal conditioner and reprimed using a zinc
chromate primer. This operation is to be performed
Anti-Corrosion Treatment and Repair prior to the application of sealers, waxes, deadeners,
Caution: When applying sound deadeners, or and antirust compounds. Refer to Basecoat/Clearcoat
anti-corrosion materials due care and Paint Systems
preventative measures must be exercised to These sealers are intended to prevent water and
prevent any material from being sprayed into dust from entering the vehicle and also are
door and quarter panel mechanisms such as anti-corrosion barriers. Sealers are applied to such
door locks, window run channels, window areas as rear compartment lid hem flanges,
regulators and seat belt retractors, as well as any wheelhouse, quarter outer, floor, cowl, roof, and
moving or rotating mechanical or suspension various other panel to panel attaching points. The
parts on the underbody, particularly the parking originally sealed joints are obvious and any damage
brake cable. After material application, be sure to these sealed locations should be corrected by
that all body drain holes are open. Improper resealing. Attaching points of new replacement
application may increase chance of corrosion panels should be resealed. Replacement lids
damage or limit the operation of moving parts, and doors will also require sealing in the hem
resulting in personal Injury. flange areas.
1998 -
MD-lsuzu
Flanged joints, overlap joints, and seams should be Cleaning of the interior and underbody panel
sealed using a quality sealer of medium-bodied surfaces is necessary when original galvanized or
consistency. The sealer used must retain its flexible other anti-corrosion materials have been burned off
characteristics after curing and be paintable. during welding or heating operations. Removal of the
residue from burning will require additional care in
Open joints which require bridging of the sealer to such areas as interior surfaces of box-type
close a gap should be sealed using a heavy-bodied construction and when configurations of the metal
caulking material. Follow the label directions for the panels limit access to interior surfaces. One or more
material selected. of the following methods will remove the residue.
Color application may be required to restore repaired Sandblasting is an excellent method for cleanup
areas such as hood, fenders, doors, quarters, lid, and preparation of open joints, underbody
roof, engine compartment, underbody, and inner components, and hem flange areas.
panels to original appearance. When this is Sandblasting is most effective and should
necessary, conventional refinishing preparation, be used.
undercoat buildup, and color application techniques
When access is possible, scraping with a putty
should be followed. Refer to Basecoat/Clearcoat knife or scraper can be used.
Paint Systems. A jet of compressed air will remove most
Deadener materials (spray-on type) are used on residue and could be effective in a limited
various metal panels to provide corrosion resistance access areas.
and joint sealing. They control the general noise
level inside the passenger area of the vehicle. When
deadeners are disturbed because of damage, are
removed during repair operations, or a new
replacement panel is installed, the deadener material
must be replaced by a service equivalent material.
The application pattern and location of deadener
materials can be determined by observing the
original production installation.
Anti-corrosion compounds are light-bodied materials

designed to penetrate between metal-to-metal
surfaces, such as pinch weld joints, hem flanges,
and integral panel attaching points where metal
surfaces are difficult to coat with conventional
undercoating materials, and are inaccessible for
painting. Conventional undercoating is recommended
to coat large areas such as replacement door and
quarter outer panels, floor pan sections, lids, hoods,
fenders, etc. During undercoating operations, care
should be taken to prevent the material from being 142047
sprayed into door and quarter panel hardware

mechanisms such as door locks, glass run channels,
window regulators, and seat belt retractors. On the
underbody, the material should not be applied to any
moving or rotating part, energy absorbing bumper
components, or shock absorbers. After undercoating,
make sure that all body drain holes are open. Refer
to Basecoat/Clearcoat Paint Systems for the
sequence of application steps for anti-corrosion
materiols.
142049
1998 -
MD-lsuzu
142064
Paint Identification
Caution: Exposure to isocyanates during paint

preparation and application processes can cause
severe breathing problems. Read and follow all of
the instructions from the manufacturers of painting
materials, equipment, and protective gear.
The Basecoat/clearcoat paint is factory applied in
four layers: a cathodic immersion primer, a
primer/surfacer, a basecoat, and a clear top coat
(clearcoat) to give the finish a high gloss look. To
identify the type of top coat on the vehicle, you may
refer to the Service Parts Identification Label. This
label contains all paint related information for the
vehicle. This includes paint technology, paint codes,
trim level, and any special order paint colors.
142058
1998 -
MD-lsuzu
Standing rinse water should be dried promptly
and not allowed to dry on the surface.
Drying with a soft chamois is recommended.
'
SFViCE PARTS IDENTIFICATION DO NOT RFMOVF
Do not polish vehicles unless a surface
LISTL DLS OPTIONS condition exists that can only be corrected by
polishing. Refer to Clearcoat Repair
Specifications Meguiar Products or Clearcoat
-
Repair Specifications 3M Products.

-
If a surface condition does exist, the repair

approach should be one of less is best (the
very least it takes to correct the condition).
Avoid removing too much clear coat (whenever
possible, use paint gages before, during and
after polishing). Refer to Paint Gauges.

Use only the products recommended in this
procedure (or their equivalent). Refer to
Clearcoat Repair Specifications Meguiar
-
Products or Clearcoat Repair Specifications -
3M Products.
65485

Make sure that any power polishing equipment
Legend does not exceed the requirements in the polish
(1) Vehicle Identification Number manufacturers recommendations. The final
(2) Engineering Model Number (Vehicle process step typically uses an orbital type
Division, Vehicle Line and Body Style) polisher with speeds of 1,500 to 2,000 R.P.M.
(3) Interior Trim and Decor Level Refer to Clearcoat Repair Specifications -
Meguiar Products or Clearcoat Repair

(4) Exterior (Paint Color) WA Number Specifications 3M Products.
-
(5) Paint Technology Don't use wax or silicone type products to hide
(6) Special Order Paint Colors and Numbers swirl marks (this damage will reappear later and
(7) Vehicle Option Content cause customer dissatisfaction).
Specific conditions on the paint (environmental
damage, rail dust, etc.) can be corrected by:
Repair Instructions
Refer to Environmental Fallout (Acid Rain).
Clearcoat Repair w/o Repainting
Refer to Rail Dust Damage Repair.
1. Thoroughly wash repair area with Liquid Wash

Notice: Removing too much of the clearcoat can and Wax.
result in early paint failure. The clearcoat contains
2. Readings of the paint film build should be taken
ultraviolet screeners. Do not finesse sand more than prior to the operation. Refer to Paint Gauges.
what is required to remove the defect.
3. Apply a small amount of the appropriate
Important: material to repair area and smear evenly with
Avoid washing vehicles in direct sunlight. the pad. Refer to Clearcoat Repair
-
Avoid using strong soaps or chemical

-
detergents.

Use brushless type automatic car wash 4. With the polisher running at approximately
1,500 rpm, to 2,000 rpm polish the repair area.
equipment.
Keep the pad flat against the panel while
Avoid using products containing acids applying heavier pressure applied for
(unless specified to correct a condition such as
rail dust).
4-6 seconds, then polish with lighter pressure
for6-8 more seconds. Feature lines and panel
Don't use brushes or brooms to remove snow edges should be hand-rubbed to avoid
or ice from vehicles in storage or on lots. burn-through.
Cleaning agents and water should be dried 5. Check the repair area frequently and, if
promptly and not allowed to dry on the surface. necessary, add more of the appropriate material
Drying with if required.
a soft chamois is recommended.
1998 -
MD-lsuzu
6. Always blend or feather the outer edges of the 2. Clearcoat etching slight etching still noticeable
-
repaired area. after the above washing and finesse polishing

7. After buffing, the repaired area should be procedure, refer to Slight Clearcoat Damage
inspected. Wet Sanding, Finesse Polshing in this

If swirls are still visiable, repeat the buffing procedure.
8.
procedure. 3. Basecoat etching severe etching beyond the
-
clearcoat into the basecoat, refer to

9. Clean the repaired area with a clean soft,
Basecoat/Clearcoat Paint Systems.
non-scratching cloth with a 50/50 mixture of
IsopropyI Alcohol and water. Slight Clearcoat Damage
Wet Sanding,
10. If sanding is required, refer to Clearcoat Repair Finesse Polishing
-

-
Notice: Removing too much of the clearcoat can
result in early paint failure. The clearcoat contains
ultraviolet screeners. Do not finesse sand more than
Corrosion Repair
what is required to remove the defect.
Caution: When applying sound deadeners, or
Important: Always refer to manufacture's packaged
anti-corrosion materials due care and instructions for the detailed procedures of materials
preventative measures must be exercised to used for compounding or polishing.
prevent any material from being sprayed into
door and quarter panel mechanisms such as 1. Select small test area on the damaged panel.
a
door locks, window run channels, window 2. Readings of the paint film build should be taken
regulators and seat belt retractors, as well as any prior to the operation, refer to Paint Gauges.
moving or rotating mechanical or suspension
3. Wet sand the damaged area with an ultra-fine
parts on the underbody, particularly the parking sandpaper and rubber sponge sanding block.
brake cable. After material application, be sure Refer to the manufacture instructions for
that all body drain holes are open. Improper detailed procedures for the materials used in
application may Increase chance of corrosion the repairs. During the wet sand process:
damage or limit the operation of moving parts,
resulting in personal injury. 3.1. Use ample amounts of water.
Caution: Approved safety glasses and gloves 3.2. Go slow to prevent removing too much
clearcoat.
to reduce the chance of personal injury. 4. Remove the excess water with rubber
squeegee and inspect area. If wet sanding has
Prior to replacing exterior body parts, check the
repaired the damage, continue the sanding
condition of the paint on all covered or hidden procedure on the entire panel.
interior surfaces. If rust scale is found in these
5. Apply a finesse-type polish with a foam pad
areas, proceed as follows:
and remove any swirl marks with a dual action
1. Remove rust with wire brush, abrasive or liquid orbital polisher and foam pad. Refer to
rust removing agent. Follow label directions. Clearcoat Repair Specifications 3M Products
-
2. If necessary, wash with detergent, rinse or Clearcoat Repair Specifications -
Meguiar
and dry. Products. If (during the repair) it is suspected or
observed that etching has penetrated into the
3. Apply a heavy coating of anti-corrosion
compound to all cleaned hidden surfaces before basecoat, too much clearcoat has been
installing exterior body parts. Apply removed during sanding or base color is
anti-corrosion compound to all inner surfaces of transferred to pad during polishing, the affected
exterior body parts being installed. areas may require clearcoat/basecoat
application or refinishing. Refer to
Environmental Fallout (Acid Rain) Basecoat/Clearcoat Paint Systems.
Since the severity of the condition varies from area 6. Polish the eniire vehicle after all damage has
to area, proper diagnosis of the damage extent is been repaired.
critical to the success of repairs. Diagnosis should
be performed under high intensity fluorescent Surface Level Contamination Repair
lighting, on horizontal surfaces (hood, roof panel, Notice: Removing too much of the clearcoat can
rear compartment lid) after they have been properly result in early paint failure. The clearcoat contains
cleaned. There are three basic types of acid rain ultraviolet screeners. Do not finesse sand more than
damage: what is required to remove the defect.
1. Surface level contamination may be repaired
-
Important: Always refer to manufacture's packaged

by simply washing the vehicle, cleaning the instructions for the detailed procedures of materials
surface with a silicone, wax and grease used for compounding or polishing.
remover, neutralizing acidic residue and finesse
polishing, refer to Surface Level Contamination 1. Thoroughly wash the repaired area with Liquid
Repair in this procedure. Wash and Wax, and dry thoroughly.
7998 -
MD-lsuzu
2. Clean affected area with silicone, wax and Clearcoat Thickness

grease remover. The Clearcoat on the vehicle is typically
3. Neutralize left over acidic residue by cleaning 0.059 to 0.078 mm (1.5 to 2 mils; 0.0015
damaged areas with mixture of baking soda to 0.0020 inch) thick.
and water (one tablespoon of baking soda per
one quart of water). Rinse thoroughly and dry Rail Dust Damage Repair
panel completely.
Caution: Approved safety glasses and gloves
4. Apply finesse-type polish with foam panel. If should be worn when performing this procedure
damage has been repaired, remove any swirl
to reduce the chance of personal Injury.
marks with dual action orbital polisher and foam
pad. Refer to Clearcoat Repair Specifications -
Important: If rail dust has penetrated into the
3M Products or Clearcoat Repair Specifications basecoat, the panel requires refinishing. Make sure
-
Meguiar Products. all the rail dust has been removed prior to refinishing
or the rust spots will return.
5. If some damage remains, refer to Slight
Clearcoat DamageWet Sanding, Finesse Rail dust damage comes from the tiny iron particles
Polishing in this procedure. produced from the friction between the train wheels
and the track. It can also be deposited on vehicles if
Paint Gauges stored near any operation producing iron dust (i.e.,
The best way to accurately measure how much steel ore yards). This dust can either lay on top of,
Clearcoat has been removed is to use a paint gauge or embed into the paint surface. It is usually
before, during and after the sanding process. Paint diagnosed as bumps in the paint surface or rust
gauges measure the total thickness of the finish and colored spots in the paint.
when used, can determine how much Clearcoat has 1. Move the vehicle to a cool shaded area and
been removed during the repair process. Paint make sure the vehicle surfaces are cool during
gauges range from magnetic pull type to the removal process.
sophisticated electronic types and are available from
a variety of sources. The older magnetic type gages, 2. Thoroughly wash repair area with Liquid Wash
and wipe dry.
at best have a 5 percent accuracy range and are not
sensitive enough to detect removal of 0.020 mm 3. Clean the affected area with silicone, wax and
0.5 mil; (0.0005 inch) Clearcoat. The newer type grease remover.
magnetic gauges have improved accuracy ranges. 4. Perform the removal process according to the
Most gauges are confined to checking either ferrous manufacture's directions of the type of repair
metal (steel) or non ferrous metal (aluminum) panel. material used (Gel Type Oxalic Acid or Clay
At this time, there are no viable gages for reading Type Non-Acid Based). If, upon inspection,
film thickness on nonmetallic panel. The more some particles are still present, the process can
sophisticated (ETG) Electronic Paint Thickness be repeated. If the damage has been repaired,
Gauges digital type gauges are able to read film complete the repair to the entire panel.
thickness on both ferrous and non-ferrous metal
5. Polish the entire panel after the removal
panel. Digital (ETG) gages can have an accuracy
process, refer to Clearcoat Repair Specifications
range of 1 percent and include thickness standards 3M Products or Clearcoat Repair
-
for recalibration. Specifications Meguiar Products, if small pits

-
remain in the Clearcoat after all damage has

been repaired. Refer to Clearcoat Repair w/o
Repainting.
1998 -
MD-lsuzu
Body and Accessories Frame and Underbody 8-463
Frame and Underbody

Specifications

Specification
Assist Step Bolt 45N.m 33lbft
Crossmember Bolt/Nut 70 N.m 52lbft
Tow Hook Bolt 163 N.m 120lbft
Yield Strength of Different Metals

Specification
Metal Types kPa psi
SAE J-1392-050 344,750 50,000
SAE J-1392-080 551,600 80,000
SAE 1027 (Heat Treated) 758,400 110,000
Welding Table
Materials Used SAE J-1932-050 J-1392-080
Process GMAW SMAW SNAW
Electrode E70S-3 E7016, E7018 E11018

Minimum Yield of Electrode 413,700 kPa (60,000 psi) 413,700 kPa (60,000 psi) 668,815 kPa (97,000 psi)
Chamfer Used When Cutting
Away the Sides of a Crack to 60- 90- 90-
Be Welded
Electrode Table
Electrodes E-7011, E-7016 E-7018, E-11018
Flat Welding
Available Sizes Current Range (Amps) Arc Voltage

5/64 in x 9 in 30-60 20-22
5/32 in x 12 in 45-80 21-23
1/8 in x 14 in 80-115 21-23
5/32 in x 14 in 125-165 22-24
3/16 in x 14 in 160-200 22-24
7/32 in x 18 in 200-250 23-25
1/4 in x 18 in 250-320 23-25
5/16 in x 18 in 325-400 24-28
Overhead Welding
Available Sizes Current Range (Amps) Arc Voltage
3/32 in x 12 in 45-75 20-22

1/8 in x 8 in 80-125 20-24
5/32 in x 14 in 120-190 21-24
3/16 in x 14 in 150-240 21-24
1998 -
MD-ISUZU
8-464 Frame and Underbody Body and Accessories
Plug Weld Chart

Thickness of Material Diameter of Plug Depth of Plug
6 mm (1/4 in) 19 mm (3/4 in) 6 mm (1/4 in)
10 mm (3/8 in) 25 mm (1 in) 10 mm (3/8 in)
13 mm (1/2 in) 29 mm (1 1/8 in) 11 mm (7/16 in)
16 mm (5/8 in) 32 mm (1 1/4 in) 13 mm (1/2 in)
19 mm (3/4 in) 35 mm (1 3/8 in) 14mm (9/16 in)

25 mm (1 in) 38 mm (1 1/2 in) 14mm (9/16 in)
Use a plumb bob to transfer the points on the

Diagnostic Information and 4.
rails to the floor directly beneath the rails.
Procedures
5. Move the vehicle away from the points on
Checking Frame Alignment the floor.
Checking with Gauges 6. Mark a chalk line through the points

representing each of the rails.
The various types of frame misalignment may be
divided into the following groups: 7. Measure the distance between each point and
the line representing the rail. The distance
Sag
should be not be more than 3 mm (0.12 in). A
Buckle distance greater than 3 mm (0.12 in) indicates

Diamond side sway.
Side Sway 8. Measure the distance between the web at the
Twist end point of the rear section of the rails. The
distance should measure 851 mm (31.5 in).
A misaligned frame may have moved forward from,
upward or downward from, or to the side of the 9. Measure the distance between the inside of the
frame's original position. Inspect the vehicle when frame rails at the front of the frame. This
such conditions are present. The most efficient way distance should be 851 mm (31.5 in).
to check frame alignment is to use gauges. Detailed 10. Measure the length of each of the rail lines.
instructions are normally supplied with the gauges at Each rail line should be the same length.
the time of purchase. You can, however, check the 11. Mark a point on one of the rail lines, a given
frame alignment without gauges. Refer to Checking distance from one end of the vehicle. Mark a
without Gauges. point on at the same spot on the other rail line.
Whether you check alignment with or without
12. Mark a pair of diagonals from the two points on
gauges, park the vehicle on a level section of the rail lines to the opposite rail. Make the
the floor. diagonals the same length.
Certain conditions call for some preliminary checks
before actually checking the frame. Suspension or
axle problems may be mistaken for frame
misalignment. For example, a shifted axle may
appear to be frame diamond or side sway. A weak
spring may appear to be a twisted frame.
A visual inspection on the top and the bottom of the
flanges of each rail may reveal an area on which
sag or buckle exist. In the case of sag, wrinkles will
appear on the top of the upper flange. Such wrinkles
are definite evidence of sag. Wrinkles on the bottom
or the lower flange are definite evidence of frame
buckle.
Checking without Gauges

1. Move the vehicle to a level, well-lit section of
the floor.
2. Make a diagram of the frame on the floor under
the vehicle.
3. Pick several points on the bottom flange of
each of the frame rails. Leave clear access 207483
from these points to the floor. Mark one point at
the rear end of each of the rails. Ensure that all
of the points are the same distance from the
vertical part (web) of the rail.
1998 -
MD-lsuzu
13. Mark a second pair of diagonals from the The following steps offer an alternative method of
original two points on the rail lines to the checking the vertical alignment of a normally
opposite rails. The second pair of diagonals straight rail:
should be the same length as each other, but
1. Measure the distance from the frame rail to the
longer than the first pair of diagonals. floor at several different points along the rail.
14. Mark a line between the points of the The vehicle must be on a level section of
intersection of the two pairs of diagonals. This the floor.
line should be the same distance from each of
2. Transfer these distances, in order, to a sheet of
the frame rails at any given point along their graph paper.
edges.
3. Connect the points, representing each distance,
on the graph paper.
4. If the rail is straight (vertically), the points
should all lie on a straight line.
Frame
Sag
Problem Action
The vehicle is overloaded.
The load distribution of the vehicle is uneven.

Abrupt changes in section modulus.
Improper body or accessory mounting, including the following

situations:
Holes drilled in the flange of the frame rail
Too many holes in the web section of the rail

More than four holes in the same vertical line of the Straighten and reinforce the frame. Refer to Frame
rail web Straightening Description.
Welds on the flange, particularly across the flange or
along the edge of the flange
Cutting holes in the rail with a torch
Cutting notches anywhere on the rails
A vehicle fire.
A vehicle collision,
The use of improper equipment.
Buckle
Problem Action
Operating an overloaded dump truck with the box raised.
The surging of liquids in a tank truck.

Straighten and reinforce the frame. Refer to Frame
A vehicle collision.
Straightening Description.
A vehicle fire.
Side Sway
Problem Action
A vehicle collision.
A vehicle fire.
1998 -
MD-lsuzu
Diamond
P roblem Action
A vehicle collisi on.
c
Towing another vehicle with a chain attached to one comer Straightening Description.
of the frame.
Twist
Problem Action
A vehicle collision. Straighten and reinforce the vehicle. Refer to Frame
Operating the vehicle on excessively rough terrain. Straightening Description.
improper Tracking
Problem Action
The frame is not aligned properly. Straighten and reinforce the frame. Refer tc3 Frame
Shifting of the front or rear axle. Realign and secure the axle.
The wheels are out of alignment. Align the wheel. Refer to Wheel Alignment Specifications in
Wheel Alignment.
Cracks in the Web of the Rails

Problem Action
Loose crossmember attaching bolts. Replace, or weld and reinforce the rail.
Stress concentration. Refer to Minimizing Frame Service 1. Ream the bolt holes and install larger bolts if
Description. necessary.
2. Tighten the bolts. Refer to Fastener Tightening
Specifications.
Frame Conditions Straight Trucks
Analyzing Damage
This analysis does not cover the causes of all
possible frame problems. However, it may provide
valuable assistance with preparing reports.
Frame damage does not happen without a cause.
The cause of damage is not always as apparent as
it may be in a collision.
Frame damage may be broken up into the following

classifications:
Collision

Excessive bending movement

Localized stress concentration
Repair the damage caused by a collision by using
the proper methods and reinforcements.
Excessive bending movement damage is caused by
overloading, improper weight distribution, or
misapplication of the vehicle. Excessive bending
movement damage will occur at different areas on
221511
various types of vehicles.
Maximum bending movement occurs in the area
near the rear of the cab on vehicles that have cab
or platform bodies. Overloading or loads dispersed in
diminishing quantities, allowing the balance of a load
to remain in the extreme front of the body, may
cause damage.
1998 -
MD-lsuzu
Stress Concentration Repair Instructions

Localized stress concentration failures may result
from bending movement stresses. However, the Frame Straightening Description
stress levels would not be high enough, in the Notice: Some frames are constructed of heat-treated
aforementioned instances, to cause any difficulty steel. Do not weld or drill these frames. The use of
without localized stress concentration points. These
heat, in excess of 606' C (1200' F), can weaken,
localized stress concentration points may result from
cause distortion and change the characteristics of
poor body mounting, special equipment, or defective the steel.
material. They may also occur as a result of high
bending loads, coupled with severe torsional loads Frame straightening may be a complicated process
such as off-road service. and usually requires some special equipment. Only
trained technicians should perform a frame
Use wood sills between the main rails and the straightening procedure.
sub-frame on the body installation in order to ensure
a satisfactory load distribution. Conduct a complete analysis of the frame condition
before beginning the straightening process in order
Special equipment or accessory installation may
to determine the correct sequence of steps for the
cause high stress concentrations due to the method
repair procedure. Refer to Frame and Minimizing
of attachment or the weight of the equipment. Do not
Frame Service Description. Identify the frame
drill holes through the flanges. Avoid rapid changes
material before beginning the repair procedure. Refer
to the section modulus that usually occur when large
to Frame and Underbody Description.
mounting plates are added for the support of special
equipment. Mounting heavy equipment across the Adhere to the following instructions while conducting
flanges or on the web of a side rail may cause the repair procedure:
enough stress concentration to cause damage at any Apply pressure from different directions in order
of the following locations: to reverse the flow of damaging forces.
The nearest crossmember Control the temperature and the application of

The bracket the heat.

The other frame stiffener

Heat the frame using a large sized tip
(multi-hole heating tip) and a neutral flame.

Through a nearby hole in the frame flange
Keep the oxygen opened just enough to
remove the feathers or the stringers from the
blue center at the tip of the torch.

Heat the area that will be stretched as the
frame is straightened.

Heat the area after exerting sufficient pressure.
A slight checking or some silvery cracks will
appear on the surface of the metal when
heating it at an adequate pressure.

Gradually increase the pressure while heating
the metal.
A red glow is an indication of overheating.
1998 -
MD-lsuzu
Frame Repair
^ Reinforcement Description
Reinforcements increase frame strength by
increasing the section modulus of the reinforced
area. An effective reinforcement must compensate
for any factors that could cause damage to the
frame, while not introducing any new factors that
may cause stress concentrations. While a
reinforcement is intended to make the frame (1) less
flexible, an excessively stiff reinforcement may cause
frame failure.
Adhere to the following guidelines when selecting the
type or length of a reinforcement:

Use reinforced rails, rather than the heavier
one-piece rails, on a new vehicle. Add
reinforcements if the unsupported span between
the axles is too great due to a long wheelbase.
Avoid abrupt changes in the section modulus
207501 by using tapered reinforcements.

Use the specified practices when welding,
drilling, or using bolts in a reinforcement
procedure. Refer to Welding Chart, Electrode
Chart, Plug Weld Chart, and Fastener
Tightening Specifications.

Metals vary in type and strength. The strength
of a reinforcement should be as high as the
frame that it is reinforcing. Refer to Yield

Strength of Different Metals.
Reinforcement Types
Any incorrect (1) reinforcement practices may cause
abrupt changes to the section modulus.
Follow the correct (2) reinforcement practices
carefully to avoid any frame damage.
The following types of reinforcements may be
combined in different ways to meet any special
needs (i.e. heavy demands):
207504
1998
MD-ISUZU
Use an inverted L reinforcement on either the
inside or the outside of the frame rail. Use the
inverted L reinforcement where the maximum
stress occurs on the upper flange and where
the frame or hanger-bracket design does not
allow the use of an upright L reinforcement.
207484
Use channel reinforcements on the inside or

the outside of the frame rail in order to
reinforce the flange and the web rail.
207486
Use web reinforcements, plug welded at

200-500 mm (7.87-19.68 in), on the inside of
the rail web.
207489
199S -
MD-lsuzu
'0 Frame and Underbody Body and Accessories
Use strap reinforcements, plug welded at

150-200 mm (5.9-7.87 in) intervals (1), on the
rail flange on the inside of the channel. Do not
weld across the end or along the edges of the
reinforcement.
207491
Use fish plate reinforcements on the outside of

the rail web, extending above or below the rail,
to stiffen the frame.
207493
Use an upright L reinforcement on the inside or

the outside of the frame rail. Use an upright L
reinforcement where the maximum stress
occurs on the bottom of the lower flange.
207494
1998 -
MD-ISUZU
Use inverted J reinforcements, attaching only to

the web section, on the inside of the rail
channel. The inverted J reinforcement is
designed to prevent any flange buckling due to
high torsional inputs or shock loading during a
tractor hook-up operation.
207497
Creating Reinforcements
Observe the following practices when creating a
reinforcement of any type:

Taper the reinforcement plates in order to avoid
any abrupt changes in the section modulus.
Ensure that the angles at the edge of a
reinforcement plate are less than 45 degrees.
Grind away any cracks, nicks, or burrs when
using a cutting torch to shape the reinforcement
plates. Remove any burrs from the edges of
the holes.
Avoid the gaps that may result when the
reinforcements stop short of the ends of the
crossmembers, gussets and brackets.

Make the reinforcements long enough to extend
beyond the critical area, after tapering.
Attachment
Attach all reinforcements with rivets or, preferably,
207507
bolts. In some cases, welding may be acceptable. For
example, a plug weld is used on a strap or a web
reinforcement. It is acceptable to ream an enlarged or
irregularly worn bolt hole in order for it to accept the
next larger bolt diameter. Body-fit bolts with hardened
washers may be used on critical areas. When using a
body-fit bolt, ream the hole to a non-standard size to
get an interference fit for the bolt. Use existing holes
whenever it is possible. If it is necessary to make new
holes, use a cobalt high-speed drill. Sharpen the drill
to give a 150 degree included angle with a lip
clearance of 7-15 degrees. Avoid enlarging a pilot hole
in successive stages and also avoid breaking through
to the full size at the bottom of the hole. Remove the
lip of a hole with a reamer. Observe the following
guidelines when attaching reinforcement:
Bolt the reinforcements to the frame.

Use existing holes if possible.

Do not drill holes in heat-treated frames.

Do not drill any holes in the frame flange.

Make the holes as close to the neutral axis
(halfway between the flanges) as possible.
1998 -
MD-lsuzu

Do not make any bolt holes larger than the
holes already in the frame, such as for the
spring bracket bolts.

Do not allow more than three holes on any
particular vertical line of the web.
All of the holes should be at least 13 mm
(0.5 in) apart from each other.
All of the holes in a reinforcement plate should
be at least two times the material thickness
from the edge of the plate.
Repairing Cracks
Straight cracks (1) and sunburst cracks (2) are the
two common types of cracks found in a frame.
A straight crack usually starts from the edge of a
flange, spreads across the flange, goes through the
web section of the rail, and then continues through
the other flange. A straight crack results from stress
concentrations, excessive bending movement, and
torsional loading. Refer to Minimizing Frame Service
Description.
A sunburst crack radiates out from a hole in the web
section of a rail or a crossmember. Applying a high
load at a mounting bracket or a crossmember that is
not securely attached to the rail may cause a
sunburst crack.
If the rail and the reinforcement both crack at a
particular area of the frame, repair each part
separately. The flanges must react independently in
order to prevent a localized stress concentration.
Use a copper spacer between the flanges of cracked
base rail flanges and cracked reinforcement flanges.
Use the same procedure for a crack in the
crossmember mounting flange as for a crack in the
side rail. However, when repairing a crack in the
crossmember mounting flange, build up the weld
bead in order to provide a smooth surface. Replace
any excessively damaged crossmembers.
You may need to align the frame and level the rails
before repairing the frame.
Use the following procedure in order to repair a
crack in any rail, reinforcement, or crossmember that
is not made of a heat-treated steel:
1. Remove any equipment inhibiting access to

the crack.
2. Drill a 6 mm (0.23 in) hole in the extreme end
of the crack.
3. V grind the entire length of the crack from the
starting point to the 6 mm (0.23 in) hole in the
extreme end. The angle of the V depends on
the type of welding process that is used. Refer
to Welding Chart for the appropriate angle.
4. Open up the bottom of the crack 2 mm (0.07 in)
in order to allow an adequate penetration of the
weld using a hack saw blade.
5. Weld the crack with the appropriate electrode
and welding technique. Refer to Electrode Chart
and Welding Chart.
6. Grind the weld until it is smooth on the inside
and the outside of the rail or the crossmember.
Remove any weld build up or notches on the
edge of the flange.
1998 -
MD-lsuzu
Crossmember Replacement
Removal Procedure
1. Remove the wires and the cables.
2. Remove any other lines that are connected to
the crossmember.
3. Remove the brackets and the valves.
4. Remove any other components that are
mounted on the frame and may interfere with
the removal procedure.
5. Remove the bolts or the rivets that are holding
the crossmember to the frame rails. Support the
crossmember while performing this step.
6. Remove the crossmember.
Notices.
1. Connect the crossmember to the frame rails

with the bolts, the washers, and the nuts or
the rivets.
Tighten
2. Install the brackets and the valves.

3. Install any other components that were
previously removed.
4. Install the wires and the cables.
5. Install any other lines that were previously
removed.
Body Mount Replacement (Cab Mounts)

Removal Procedure
Notice: The cab must be properly supported and the
weight of the cab evenly distributed during cab
mount replacement. Failure to provide proper support
could result in damage to the vehicle.
1.Raise the cab.

2. Mark the shaft and gear in order to aid in
reassembly.
3. Remove the steering shaft at the steering gear.
5. Fasten a rope securely to the cable lock. Use a
hoist or a chain block in order to keep the cab
tilted.
6. Remove the torsion bar levers.
215792
1998 -
MD-lsuzu
t-474 Frame and Underbody Body and Accessories
215795
8. While slowly lowering the cab, remove each

one of the center pins by tapping it with a
hammer.
215794
9. Perform the following procedure. Keep in mind


window openings.
9.5. Lift the cab from the chassis just enough
to clear the mounts.
215784
)998 -
MD-lsuzu
10. Remove the front cab mount assembly from
the frame.
Notices.
1. Install the front cab mount assembly to

the frame.
Tighten
215816
2. Slowly lower the cab into position.
215784
1998 -
MD-lsuzu
3. Install the center pins (left and right).
4. Hook a wire to the cab striker, pull the safety

lever, and tilt the cab slowly. Use the wire in
order to keep the cab from floating up.
5. Install the cab tilt support to the cab.
6. Lower the bracket.
Tighten
215794
7. Lower the cab until the hole in the cab support

inner channel aligns with the top hole in the
cab support outer channel.
8. Install the following items:

The pin

The washer
The cotter pin
215795
9. Perform the following in order to install the

torsion bar levers.

Locate the left and right identification marks.
Match the serrration.
Install the torsion bar levers.
Tighten
Tighten the bolt/nut to 37 N.m (27 Ib ft).
215792
1998 -
MD-ISUZU
10. Apply grease to the steering shaft.
11. Use the match marks made during disassembly
as a guide to install the steering shaft.
12. Securely insert the steering shaft and the
steering unit to the far end.
13. Tighten the key bolt.
Tighten
14. Lower the cab.
Body Mount Replacement (Cab Mount)

Removal Procedure
1. Raise the cab. Refer to Cab Replacement in
2. Remove the mount from the upper bracket.
3. Remove the following items:
The through bolt

The spacer

The washers
4. Remove the upper bracket.

5. Remove lower bracket.
215826
1998 -
MD-lsuzu
V7Q Frame and Underbody Body and Accessories
6. Remove the rear body mount from the frame.
215830

Notices.
1. Install the rear body mount to the frame.

Tighten
2. Install the lower bracket.

Tighten
215830
3. Install the upper bracket.

Tighten
4. Install the following items:

The through bolt

The spacer

The washers
215826
1998 -
MD-ISUZU
5. Install the mount to the upper bracket.
6. Lower the cab.
215823
Body Mount Replacement (Bracket)

Removal Procedure
1. Release the cab lock.
2. Remove the bolts from the bracket.
3. Remove the bracket from the cab.
215834
Notices.
1. Install the bracket to the cab.

Tighten
2. Latch the cab lock.
215834
1998 -
MD-ISUZU
Tow Hook Replacement

Removal Procedure
1. Remove the tow hook to frame bolls, washers,
and nuts.
207535
2. Remove the tow hooks and brackets.
207538
1. Install the tow hooks and brackets to the
frame rails.
207538
1998 -
MD-lsuzu

Notices.
2. Install the hook to frame bolts, washers,

and nuts.
Tighten
Tighten the nuts to 163 N.m (120 Ib ft).
207535
Assist Step and Support

Replacement Lower
Removal Procedure
1. Remove the lower assist step from the assist
step support.
2. Remove the assist step support from the assist

step support bracket.
214259
1998 -
MD-lsuzu
1. Install the lower assist step support to the
assist step support bracket.
214259

Notices.
2. Install the lower assist step to the assist step

support.
Tighten
2.1. Tighten the lower assist step bolt to
45 N.m (33 Ib ft).
2.2. Tighten the lower assist step nut to
23 N.m (17lbft).
214253
1998 -
MD-ISUZU
Description and Operation Frame and Underbody Description
Welding Description Identification of Material

Improper welding techniques often result in weld Notice: Some frames are constructed of heat-treated
and/or frame failures. The following information steel. Do not weld or drill these frames. The use of
describes some potential areas of difficulty and
heat, in excess of 606' C (1200" F), can weaken,
provides some general guidelines for successful
cause distortion and change the characteristics of
frame welding. This information only pertains to steel the steel.
rails that are not heat treated.
It is critical to identify the rail material before
Most weld failures occur at the end of the weld in
attempting to straighten or repair a frame. The use
the areas of the frame that are under high levels of
of any method that is not recommended for the
stress. The elimination of the ends of a weld may
reduce failures. Eliminate the ends by making a hole material may result in damage to the frame.
or a slot in the part that will be attached and using a All medium duty vehicles have modified SAE 1027
fillet weld around a slot or plug a plug weld. Do not heat-treated SAE J-1392-050, or SAE J-1392-080
leave a notch at the end of a weld. For a guide to steel rails. Measure the thickness of the frame rail in
the diameter and the depth of plug welds by the
order to identify the heat-treated frame. Take the
thickness of the welded material, refer to Welding
measurement at the front of the frame where there
Chart. In most cases, the elimination of the ends of is not any reinforcement. The heat-treated rail will
the welds will result in less welding, lower costs, and
a more successful weld.
measure 10 mm (0.39 in) thick. There should also be
an identifying label on the outside of the left rail or
Adhere to the following instructions while performing the reinforcement forward of the rear suspension.
a welding procedure:
Refer to Electrode Chart for the use of the
Do not overweld, especially in an areas of the
electrode and the chamfer according to the process
frame that receive high concentration of stress.
for welding the SAE J-1392-050 and SAE
Weld any small cracks in the crossmember. J-1392-080 rails.
Refer to Frame Repair.
Refer to Electrode Chart in order to determine Frames
the appropriate electrodes to use for a The components of a frame consist of the side rails
particular welding procedure. and the crossmembers. The side rails carry the load

Disconnect the vehicle battery or batteries. and the crossmembers stabilize the rails. The frame
. Do not use any oxyacetylene welding assembly must be stiff enough to support the load it
equipment. carries and flexible enough to absorb and distribute

Use electrodes with a smaller diameter. stress.
Make several passes. Do not make any more These vehicles have straight, full-channel, side rails.
passes than necessary. The rails should be parallel at all points along their
Only use as much heat as is necessary to length.
achieve adequate penetration. In order to prevent corrosion, it is necessary to apply
Make sure that the weld is free from craters a batten compound to the mating surfaces of
and undercuts. dissimilar metals, such as an aluminum battery box
that is mounted on a steel frame rail.

Remove the scale from each successive pass.
. Grind the surface of the weld flush with the Attach the frame components by using grade
parent material when repairing a crack. 10.9 bolts or huck fasteners. Use prevailing torque
nuts and hardened washers at each end of the bolts.

Do not weld across the flanges when mounting
any accessories. The proper frame alignment is critical to the

Do not weld within 19 mm (0.75 in) of a flange durability and the function of many other parts of the
when mounting any accessories. vehicle. If the vehicle has been involved in a fire, a
collision, or has been overloaded, check the frame

Leave at least 6 mm (0.23 in) between the end
of a weld and the edge of the part. alignment. Check the alignment if improper alignment
is suspected for any other reason. Refer to Checking
Do not weld the cast brackets to the frame.
Frame Alignment.
Do not weld together the flanges of any
cracked reinforcements and base rails.

Do not attach the ground cable to the engine.
Connect the welding machine ground cables as
close to the working area as possible.

Keep the welding cables away from the vehicle
wiring. Avoid any direct contact between the
welding cables and any part of the vehicle.
1998 -
MD-lsuzu
Minimizing Frame Service Description Adhere to the following recommendations when

repairing a frame and when mounting a body,
Reducing the concentration of stress in the small
or any other equipment, onto a frame:
areas of the frame may often minimize of eliminate
the occurrence of frame failure. The following -
Avoid any sudden changes in the section
information may assist in such a reduction: modulus.

Use particular vehicles only for the purpose for
-
Do not drill any holes in the frame rail
which they were designed. flanges.
-
Do not overload the vehicle. -
Space the holes in the web section of the
rail at least 13 mm (0.5 in) apart.
-
Load the vehicle evenly.

-
Use existing holes whenever it is possible.
-
Avoid any localized overloading.
-
Do not cut the holes with a torch.
-
Use baffles in all tank trucks.

-
Do not cut any notches in the rails.
-
Do not operate the vehicle on any extremely
rough terrain. -
Do not weld on the flanges.
-
Do not allow more than four holes to exist
on the same vertical line of the web.
-
Place any hole in a reinforcement at least
two times the material thickness away from
the edge of the reinforcement.
1998 -
MD-lsuzu
Body and Accessories Collision Repair 8-485
Collision Repair
Hole and Crack Repair
Repair Instructions 1. Holes of less than 6 mm (1/4 in) in sheet metal

panels can be welded and metal finished
Cab without backing.
Cab repairs may require reinforcements. Before 1.1. Degrease and mechanically clean the
reinforcing any part of the vehicle, find the cause of area on the panel(s) with emery cloth or
the failure. Cab panels and framing are integral, an abrasive wheel.
therefore driving stresses and strains are transmitted 1.2. Weld the hole using a filler rod and any
throughout the cab. Reinforcing a point of an of the E70S-1 through E70S-6
apparent failure without correcting the underlying electrodes.
problem may transfer the stress to other parts of the
1.3. Metal finish the area if the panel surface
cab, causing new failures to develop. is visible.
The use of heat when straightening structural parts 2. Holes greater than 6 mm (1/4 in) in diameter
of the body is not recommended. Heat will affect the but less than 50 mm (2 in) in diameter can be
structural characteristics of the material. Any parts welded by backing the hole with the same
bent or buckled enough to show strain cracks after material as the parent material.
straightening should be replaced or properly
reinforced. 2.1. Degrease and mechanically clean the
area on the panels with emery cloth or
Any parts used that are not steel, but will contact a an abrasive wheel.
steel part, including bolts, washers, nuts, or rivets,
should be coated with paint or plating in order to 2.2. Weld in a backing plate of the same
material as the parent material using a
prevent corrosive action between the dissimilar filler rod. The minimum edge overlap at
metals. the holes should be 3 mm (1/8 in).
To maintain proper body strength, replace the
2.3. Metal finish the area if the panel surface
damaged panels or other structural parts with is visible.
new ones.
3. Cracks in the sheet metal panels that are less
Notice: Before welding inside the vehicle, protect the than 76 mm (3 in) long and 3 mm (1/8 in) wide
interior components from welding sparks or heat to can be welded and metal finished without
prevent damage to the interior. backing.
All welding should be done according to American
Degrease and mechanically clean the
Welding Society (AWS) standards. When welding panel(s) with emery or an abrasive wheel.
steel panels of a conventional cab, use TIG, MIG, or Establish the start of the crack with a
stick welding. If resistance welding equipment is
dye-penetrant test.
available, it can be used. Always use good practices
End the split by drilling a hole at the root of
as recommended by the AWS.
the split. The diameter of the hole should be
When welding a cut member, fill or weld the cut
at least one-and-a-half times the metal
completely. Filler material should be of the same thickness.
material as the parts being welded. Use any of the
Weld the crack using a filler rod and any of
E70S-1 through E70S-6 electrodes.
the E70S-1 through E70S-6 electrodes.
Cab Panel If the panel is visible, metal finish the area.
In order to maintain proper body strength, replace
Cab Alignment and Straightening
damaged structural members with General Motors
parts or the equivalent. Before attempting the repair of a damaged cab, the
Cab panels can be replaced by removing the chassis must be checked and, if necessary, aligned.
Refer to Frame in Frame and Underbody.
damaged part and welding in the new piece. For
proper alignment of the panel, clamp the panel in Do not attempt to straighten the cab unless the cab
position before welding. is firmlyattached to the chassis. The inner paneling
of the cab should be straightened first. A push-pull
Any window opening should be spot welded since
hydraulic jack together with an extension and
the window opening provides a sealing surface.
adapters is recommended for this type of repair.
When replacing a rear pane or roof panel, give
Cross-check with an adjustable tram bar as work
special attention to the proper sealing of joints with
progresses.
sealing and caulking compounds.
7998 -
MD-lsuzu
8-486 Collision Repair Body and Accessories
After straightening, it is critical that strains set up in Applying Primer Coats
the frame be "normalized" or relieved. Normalizing Prime all bare metal with an acrylic chromate
consists of heating the areas of greatest tension with material.
a torch. Hold the torch about 50 mm (2 in) from the
Applying Sealers
metal and move it over an area of 75 to 100 mm Seal all flanged joints, overlap joints, and seams with
(3 to 4 in) until the metal just begins to turn red. a medium-bodied consistency sealer that stays
Cooling must be slow to avoid changing the flexible and is paintable. All open joints that require
characteristics of the metal. Apply slight heat with a bridging of sealer to close a gap require treatment
torch, if necessary, to slow cooling. with a heavy-bodied caulking material.
Sheet Metal Repair Applying Color

If areas such as underbody, hem flanges, exposed
In order to prevent rust, special anti-corrosion
joints and engine compartment need color, follow
materials are used on the interior surfaces of metal
conventional refinishing preparation, undercoat
panels. These materials include special metals such
build-up, and color application procedures. Rub-out
as one-sided and two-sided galvanized, zincrometal,
and extensive sanding of the undercoats is not
and zinc-iron alloy steels. These specially treated
necessary.
metals are used in fenders, doors, quarter panels,
rocker panels, floor pans, and other critical areas. Applying Deadeners
Use a heavy-bodied undercoat with a rubberized or
Spray-on materials such as zinc-rich primers and
asphaltic base. Areas for application can be
waxes are also applied to interior surfaces. These
determined by original production application.
are used mainly in areas where moisture might
gather. Sealers are applied along exposed joints, and Applying Anti-Corrosion Material
moisture-repelling asphaltic sound deadeners are Use alight-bodied material designed to penetrate
applied inside wheel wells, doors, and on some between close metal-to-metal surfaces such as pinch
underbody parts. weld joints, hem flanges, and other attaching points
If the anti-corrosion treatments are disturbed while where metal surfaces are difficult to coat with
repairing damaged areas, the metals may be left conventional materials.
unprotected. This may lead to corrosion. In order to Conventional Undercoating
prevent corrosion, recoat these surfaces with Apply to large areas such as doors, hoods, fenders,/
service-type anti-corrosion materials. Follow these and the like. Do not spray material into door /
steps in applying the materials: hardware such as locks, run channels, and windovy
regulator.
Cleanup and Preparation
Depending on the location of the area, sandblasting, On the underbody, do not apply undercoating
scraping, wire brushing, sandpaper, and steel wool material to any moving or rotating parts. Do not
can be used in order to remove residue. apply undercoating to the engine exhaust system.
After undercoating, make sure that all body drain
holes are open.
1998 -
MD-lsuzu
Restraints Table of Contents 9-1
Section 9
Seat Belts..............................................................9-3 Repair Instructions.............................................9-3

Seat Belt Service Precautions.........................9-3
Specifications......................................................9-3
Fastener Tightening Specifications.................^ Driver or Passenger Seat Belt
Replacement
Diagnostic Information and Procedures .........9-3 ................................................9-4
Operational and Functional Checks center seat Belt Fleplacement......................9-11
................9-3
Description and Operation..............................9-12
Seat Belt System Operation..........................9-12
1998 -
MD-lsuzu
9-2 Table of Contents Restraints
BLANK
1998 -
MD-ISUZU
Restraints Seat Belts 9-3
Seat Belts
Specifications

Specification
Center Seat Buckle Bolt 49N.m 36 Ib ft
Lower Anchor Bolt 49N.m 36 Ib ft
Passenger Side Buckle and Center Seat Belt Bolt 49N.m 36 Ib ft
Retractor Bolt 49 N.m 361bft

Seat Belt Buckle Bolt 49N.m 361bft
Upper Anchor Bolt 49 N.m 361bft
Diagnostic Information and 4. Pull the shoulder belt completely out.

Verify that no twists remain in the
Procedures shoulder belt and that the shoulder belt
may easily slide out.
Operational and Functional Checks
5. Buckle the belt. Firmly pull the buckle in
order to ensure that the belt remains
Seat Belt Checklist
latched.
Replace the belt, the retractor and other related seat
6. Push the buckle button. Verify that the
belt components if the following conditions occur:
latch releases smoothly and that the
The belt wears due to collision. button returns smoothly to the button's
original position.

The belt webbing tears.
The belt webbing becomes highly stressed.
Repair Instructions

The seat belt buckles or the tongues corrode.

The anchor bracket bends. Seat Belt Service Precautions

The stitching on the seat belt's Energy

Sharp edges or faulty objects near the seat belt
Management Loop separates.
buckle or the latch plate may cause possible
The caution label on the belt specifies the belt damage.
replacement. Do not bend the seat belt buckle or the latch
The belt fails the following inspection: plate parts.
1. Grip the front and the rear seat belt floor
Do not bleach or dye the belt webbing.
attachments. Inspect the front and the
Clean the belt webbing with a mild water and
rear seat belt floor attachments in order soap solution.
to ensure that the seat belt floor

Use the correct anchor bolts in order to tighten
attachments are secure. Remove the the bolts to the specified torque. Verify that the
seats, if necessary, in order to reach the bolts fully seat. Allow two threads to protrude
floor attachments. Refer to Driver or
beyond the point of the nut, the anchor plate,
Passenger Seat Belt Replacement, or to and/or the anchoring device.
Center Seat Belt Replacement. Do not attempt to repair the following parts:
2. Manually grip the retractor in order to -
The retractors
verify that the retractor is securely fitted.
The buckles
Remove the trim components, if
-
necessary, in order to reach the retractor

-
The webbing
units. Refer to Exterior/Interior Trim in
Replace the complete unit with a new service
Body and Accessories. replacement assembly.
3. Verify that the shoulder belt buckles face Do not intermix seat belts from the different
inboard and are reachable. model vehicles.
1998 -
MD-lsuzu
9-4 Seat Belts Restraints
Driver or Passenger Seat Belt

Replacement
Removal Procedure
1. Remove the sill trim plate screws.
2. Remove the sill trim plate.
206138

206141
5. Remove the seat belt retractor cover screw.

6. Remove the seat belt retractor cover.
7. Remove the seat belt pass-through trim screws.
206152
1998 -
MD-lsuzu
8. Carefully pull the upper anchor bolt cover in

order to remove the upper anchor bolt.
206162
9. Remove the lower anchor bolt.
10. Remove the retractor bolt.
206167
1998 -
MD-ISUZU
Seat Belts Restraints
11. Remove the driver seat belt assembly.
206152
12. Remove the driver side buckle assembly bolt.

13. Remove the driver side buckle assembly.
206170
14. Remove the passenger seat belt assembly.
206157
1998 -
MD-lsuzu
15. Remove the passenger side buckle

assembly bolt.
16. Remove the passenger buckle assembly.
206178
1. Install the passenger buckle assembly.

and Notices.
2. Install the passenger buckle assembly bolt.
Tighten
Tighten the buckle bolts to 49 N.m (36 Ib ft).
206178
3. Install the passenger seat belt assembly.
206157
7998 -
MD-ISUZU
4. Install the driver side buckle assembly.

5. Install the driver side buckle assembly bolt.
Tighten
Tighten the buckle bolt to 49 N.m (36 Ib ft).
206170
6. Install the driver seat belt assembly.
206152
7. Install the retractor bolt.

Tighten
Tighten the retractor bolt to 49 N.m (36 Ib ft).
206167
1998 -
MD-lsuzu
8. Install the lower anchor bolt.

Tighten
Tighten the lower anchor bolt to
49 N.m (36 Ib ft).
206164
9. Install the upper anchor bolt.

Tighten
Tighten the upper anchor bolt to
49 N.m (36 Ib ft).
10. Carefully push the upper anchor bolt cover in
order to install the upper anchor bolt cover.
206162
11. Install the seat belt pass-through trim screw.
206152
(995 -
MD-lsuzu
12. Install the seat belt retractor cover.

13. Install the seat belt retractor cover screw.
206167
I 14. Install the assist handle.

206141
16. Install the door sill trim plate.

HI !^ | 17. Install the door sill trim plate screws.
^ ii if I II /
^__-____^^"^'^^^-^1
206138
1998 -
MD-lsuzu
Center Seat Belt Replacement

Removal Procedure
1. Lift upward on the floor covering in order to
remove the passenger side buckle and the
center seat belt bolt.
2. Lift upward on the floor covering in order to
remove the passenger side buckle and the
center seat belt.
206178
3. Remove the center seat buckle bolt.

4. Remove the center seat buckle.
1. Install the center seat buckle.
2. Install the center seat buckle bolt.
206174
1998 -
MD-ISUZU
3. Install the passenger side buckle and the center

seat belt.
and Notices.
4. Install the passenger side buckle and the center
seat belt bolt.
Tighten
. Tighten the passenger side buckle and the
center seat belt bolt to 49 N.m (36 Ib ft).
Tighten the center seat buckle bolt to
49 N.m (36 Ib ft).
206178

Seat Belt System Operation
The seat belt restraint system includes the front and
the rear shoulder belts.
The driver seat belt includesa reminder lamp and a
tone alarm in order to warn drivers that the seat belt

does not buckle when the engine control switch turns
to the ON position. Refer to Engine Electrical in
Engine in order to diagnose a system failure for a
reminder lamp and/or a tone alarm.
1998 -
MD-lsuzu
INDEX
A Air Brakes (cont.)

Air Dryer/Moisture Ejector
Abbreviations and Their Meanings System Check..........................................5-167
........................0-23
ABS Air Dryer or Moisture Ejector
Handling...............................................................3
A/C
Does Not Work........................................5-168
System Air Filter Replacement Air Dryer Testing
HVAC with A/C ..........................................5-150
-
Manual.............................1-145 Application
Accumulator Slow...........................................5-143
Brakes Drag
Description .................................................5-145
Brakes Inoperative
HVAC with A/C .......................................5-143
Brakes Not Operating Properly
-
Manual.............................1-171 ...................5-143
Acid Braking Uneven
Rain...............................................................8-461
Air ABS Front to Rear
Component Locations.......................................5-405 ...........................................5-144
Side to
Component Views.............................................5-408 Side.............................................5-145
Desiccant Being Expelled From
Connector End Views.......................................5-415 Purge Valve Exhaust...............................5-147
Description Double Check Valve Test
Abbreviations and Definitions......................5-453 ................5-156, 5-157
Dryer Constantly Cycling or Purging...........5-145
Basic Knowledge Required..........................5-453
Dryer Does Not Purge or Exhaust Air........5-147
General System Description........................5-453 Dryer Purge Valve Exhausting Air...............5-146
Service Precautions Dryer Safety Valve Exhausting Air..............5-146
.....................................5-452
System Description ......................................5-454 Dual Application Valve
System Operation.........................................5-454 Test.........................5-158
Front Axle Limiting (Ratio)
Diagnosis Valve Test.....................................5-158, 5-159
Diagnostic System
Check............................5-421 Grinding Sound When
Intermittents and Poor Connections............5-420 Applied....................5-145
Inflation Valve
Test.......................................5-159
Self-Diagnostics............................................5-419 Low Air Pressure Switch
Status Lamps Illuminated .............................5-149
Moisture Ejector Valve Test.........................5-160
Left, Front and Mod.................................5-438
Left, Front and
Park Control Valve
Test................... 5-151, 5-152
Sens................................5-426 Parking Control Valve
Left, Rear and Mod Test.............. 5-152, 5-153
.................................5-444 Pressure Loss w/Eng. Off -
Left, Rear and Sens................................5-432

Brakes Applied.........................................5-144
Right, Front and Mod
..............................5-441 Pressure Loss w/Eng. Off -
Right, Front and

Sens.............................5-429 Brakes Released......................................5-144
Right, Rear and
Mode.............................5-446 Pressure Protection Valve Test .......5-160, 5-161
Right, Rear and
Sens..............................5-435 Primary Air Brake Supply Rsvr
Schematic Safety Valve
Schematic Icons...........................................5-400 Test.........................5-164, 5-165
Primary Brake Indicator or Alarm
Schematic References .................................5-400
Always On................................................5-149
System Schematics......................................5-401
Special Primary Brake Indicator or Alarm
Tools.....................................................5-455
Specifications Inoperative................................................5-148
Quick Release Valve Test............................5-161
Fastener Tightening......................................5-399
Quick Release Valve w/Double
Wheel Speed Sensor Replacement
Check Test
...............................................5-162
Front..............................................................5-450 Relay Valve Test..........................................5-163
Rear..............................................................5-451 Relay Valve w/ Double Check
Air Brakes Test.............5-163
Air Dryer Reservoir Drain Valve Test..........................5-161
Replacement.....................................5-190 Reservoirs Contain Water............................5-146
Applying Pipe
Sealant......................................5-170 Safety Valve Blows
Component Views.............................................5-140 Off................................5-144
Single Check Valve
Connector End Views.......................................5-142 Test..............................5-155
Description Spring Brake Control Valve Test.................5-165
Air Dryer/Moisture Ejector Stoplamp Switch...........................................5-149
Circuit Description System Leak Test ........................................5-150
....................................5-225
Air Dryer System Testing.............................................5-148
System..........................................5-212 Towing Vehicle Protection
Air Dryer System Operation.........................5-212
Valve 5-166
Component Description................................5-209 Test..................................... 5-165,
Component Operation ..................................5-210 Trailer Air Brake Control
Test..................................... 5-166, 5-167
System Description ......................................5-208 Valve
System Operation.........................................5-209 Trailer Stoplamp Switch...............................5-150
Valves Description........................................5-212 Trailer Supply Valve Test.................5-153, 5-154
Valves Operation..........................................5-218 Double Check Valve Replacement..................5-195
Diagnosis Draining Reservoirs..........................................5-169
Air Dryer and Moisture Ejector Dual Application Valve Replacement...............5-196
Do Not Filling Air Reservoirs
Work............................................5-168 ........................................5-170
1998 -
MD-lsuzu
2 INDEX
Air Brakes (cont.) Air Drums (cont.)

Front Axle Limiting (Ratio) Valve Air Brake Chamber Replacement........ 5-264, 5-265
Replacement............................................5-198 Front................................................. 5-265,

5-266
Hose and Line Replacement ..........................5-174, Air Drum Brake Adjustment................. 5-284, 5-285
5-176, 5-177, 5-179, 5-180 Automatic Slack Adjuster
Inflation Valve Replacement.............................5-198 Replacement ................................5-247, 5-253
Park Control Valve Replacement......... 5-192, 5-205 Brake System Inspection .................................5-229
Pedal Replacement..........................................5-171 Caging the Spring Brake Chamber.................5-282
Pressure Protection Valve Replacement.........5-200 Cam Brake Assembly Replacement.... 5-233, 5-234
Quick Release Valve Replacement Camshaft Replacement
.................5-200 ....................................5-243
Quick Release Valve w/Double Check
Description........................................................5-286
Replacement............................................5-202 Diagnosis
Rear Air Brake Relay Dbl Check Valve Brake
Replacement ............................................5-204 System...............................................5-229
Drum Inspection
Relay Valve Replacement................................5-203 ...............................................5-231
Drum Refinishing..............................................5-232
Reservoir Drain Valve
Drum Replacement........................................... 5-230
Replacement.................... 5-187, 5-188, 5-199 Shoe Inspection................................................5-235
Reservoir Replacement............ 5-181, 5-182, 5-184
Reservoir Support Replacement..........5-185, 5-186 Shoe Replacement...........................................5-236
Safety Valve Specifications
Replacement...............................5-205
Schematic Components .....................................5-227, 5-228
Air Brake Dryer Schematic..........................5-132 Fastener Tightening .....................................5-227
Air Inlet Valve
Icons.............................................................5-135 Electric Actuator Replacement
Park Brake Control Schematic....................5-133
Park Brake Schematic .................................5-134 HVAC with A/C -
Manual.............................1-153
Single Check Valve Replacement....................5-194 Air Spring
Specifications Replacement
Fastener Tightening...................................... 5-113 Air
Suspension.............................................3-130
System Components ........................................5-137 Air Suspension
Towing Vehicle Protection Valve Component Locations.......................................3-109
Replacement............................................5-206 Component Views.............................................3-109
Trailer Air Brake Control Valve Connector End Views....................................... 3-110
Replacement ............................................5-207 Diagnosis
Trailer Supply Valve Replacement...................5-193 Dump Indicator Inoperative 3-111
Air Compressor .........................
Rear Air Springs Do Not Deflate ................3-110
Description
Preventive Maintance....................................... 3-112
General.........................................................5-301 Schematic
Governor Valve.............................................5-302 Schematic References.................................3-107
Governor Valve Operation ...........................5-302 Specifications
Operation......................................................5-301 Fastener Tightening .....................................3-107
Diagnosis
..........................................................5-288 Suspension Alignment...................................... 3-111
Air Compressor and Governor Valve
..........5-289 Air Suspension Relief Valve Replacement..........3-128
Governor Valve Adjustment..............................5-300
Aluminum Wheel
Governor Valve Replacement ..........................5-299
Clearcoat Damage..............................................3-89
Overhaul................................................5-294, 5-298
Replacement.....................................................5-290 Refinishing..........................................................3-89
Specifications Antenna
Fixed Antenna Mast Replacement..................8-139
Antilock Brake System
Governor Valve Adjustment.........................5-287
Bleed
Mechanical....................................................5-287 Procedure...............................................5-389
Air Distribution BPMV Hydraulic Flow
Chart............................5-304
Description Brake Pressure Modulator Valve
System Description Replacement............................................5-390
HVAC with A/C -
Component Locations.......................................5-313
Manual.........................1-165
Air Distribution System Component Views.............................................5-316
Description Connector End Views.......................................5-323
(Non-A/C).........................................1-53
Air Distributor Description
Duct Replacement Abbreviations and Definitions......................5-394
HVAC with A/C Manual.................1-162, 1-163
-
ABS
Air Distributor Duct Replacement (Non-A/C)1-27, 1-28
System.................................................5-395
ABS System Operation................................5-396
Air Drums Basic Knowledge Required..........................5-395
Air Brake Chamber Clevis
Replacement ................................5-258, 5-262 General.........................................................5-394
Service Precautions
Air Brake Chamber Overhaul...............5-267, 5-274 .....................................5-394
1998 -
MD-lsuzu
INDEX 3
Antilock Brake System (cont.)

Diagnosis
ABS Indicator Off No DTC Set Battery
...................5-385
ABS Indicator On No DTC Set Cable Replacement (Engine Electrical).............6-86
...................5-387 Charging (Engine Electrical)
Clearing Diagnostic Trouble
Codes.............5-325 ..............................6-83
Diagnostic System Charging Low or Completely Discharged
Check............................5-326
Displaying Diagnostic Trouble (Engine
Codes..........5-325 Electrical)......................................6-83
DTC Jump Starting in Case of Emergency
List........................................................5-329 (Engine
Intermittents and Poor Connections............5-325 Electrical)......................................6-85
Scan Tool Replacement (Engine Electrical)........................6-80
Diagnostics..................................5-325
Battery Box
Self-Diagnostics............................................5-325 Replacement.....................................8-383
Electronic Brake Control Module Battery 3
Disconnect.......................................................
Blower Motor
Replacement............................................5-390 Description
Schematic
ABS Schematic Control Description
Icons..................................5-309
ABS Schematic References.........................5-308 HVAC with A/C
Manual.........................1-173
-
Diagnosis
Schematics........................................................5-309
Special Blower Motor Does Not Operate at
Tools.....................................................5-398
Specifications Any Speed (Non-A/C)................................1-14
Fastener Tightening......................................5-303 Blower Motor Does Not Operate at
Tube Adapter Replacement High Speed
.............................5-394 (Non-A/C)...............................1-14
Wheel Speed Sensor Replacement Blower Motor Does Not Operate at
Low Speed Only (Non-A/C).......................1-16
Front..............................................................5-392
Blower Motor Does Not Operate at
Rear..............................................................5-393
Audible Warnings Medium Speed (Non-A/C)
.........................1-15
Diagnosis High Speed Inoperative
Chime Always ON........................................8-334 (A/C -
Manual)...........................................1-85
Chime Inoperative Inoperative at Any Speed
........................................8-334 (A/C
Fasten Safety Belt Chime Always ON........8-336 -
Manual)...........................................1-82
Automatic Transmission AT542 Allison -
Low and Medium Speeds Inoperative
^Cleaning Tips......................................................7-23 (A/C -
Manual)...........................................1-84
Description and Operation Low Speed Inoperative
.................................7-42
Diagnosis (A/C -
Manual)...........................................1-83
Dirty Medium Speed Inoperative
Fluid.......................................................7-19
Excessive Creep in First and (A/C -
Manual)...........................................1-84
Reverse Gears...........................................7-17 Motor and Fan Assembly Replacement
Excessive Slip and Clutch Chatter HVAC with A/C -
Manual.............................1-131
Only One Motor and Fan Replacment (Non-A/C) .............1-24
Range........................................7-19
Fluid Leaking into Converter Housing...........7-17 Resistor Replacement
Fluid Out of Fill Tube or Breather.................7-20 HVAC with A/C -
Manual.............................1-128
High Stall Speed Resistor Replacement (Non-A/C).......................1-21
............................................7-18
Intermittent Buzzing Noise.............................7-17 Blower Switch Replacement (Non-A/C) .................1-20
Low Lubrication Pressure..............................7-17 Body Front End
Low Main Pressure in All Ranges.................7-16 Air Scoop Replacement...................................8-395
Low Main Pressure in First Gear..................7-16 Cab Lock Replacement....................................8-388
Low Stall Speed.............................................7-18 Cab Replacement.............................................8-385
Output Shaft Seal Fluid
Leak........................7-19 Cab Tilt Support Replacement.........................8-391
Rough Component Box Replacement.........................8-384
Shifting................................................7-18
Shift Speed Too
Low.....................................7-16 Condenser Splash Shield Replacement..........8-396
Slips in All Forward Front Fender Extension Bracket
Ranges..........................7-19
Slips in Fourth and Reverse Gear Only.......7-20
Replacement............................................8-394
Slips in Reverse and First Gear Only...........7-20 Front Fender Replacement..............................8-381
Transmission Overheats in All Ranges.........7-17 Front Side Panel Replacement........................8-396
Vehicle Moves Backward in Neutral..............7-20 Specifications
Vehicle Moves Forward in Neutral
................7-20 Fastener Tightening .....................................8-377
Specifications Upper Step and Support Replacement...........8-392
Fastener Tightening........................................7-15 Wheelhouse Panel Replacement......... 8-397, 8-398
Fluid Body Mount Replacement............ 8-473, 8-477, 8-479
Capacity.................................................7-15
Automatic Transmission AT543 Allison -
Brake Caliper
Diagnosis Mounting Plate
Shift Speed Too Replacement.................5-81, 5-82, 5-83, 5-84
High.....................................7-16
Axle Replacement, Front Overhaul.................................5-70, 5-73, 5-75, 5-78
........................................3-59
Axle Shaft Replacement................................... 5-51, 5-54, 5-58
Replacement Brake Caliper and Anchor Plate Wear
Rear Drive Axle..............................................4-72 Adjustment.....................5-62, 5-64, 5-66, 5-68
998 -
MD-lsuzu
4 INDEX
Brake Dust Caution...........

....................................3
Condenser
Brake Fluid......................... Description
....................................4
Brake Pad Inspection........ HVAC with A/C -
...............................5-43 Manual.............................1-171
Brake Pads Replacement- 5-44, 5-45, 5-47, 5-49 Condenser Fan Inoperative (A/C Manual) ..........1-85
-
Brake Pedal Replacement. Condenser Fan On at All Times

..............................5-25 (A/C
Brake Warning System -
Manual)...........................................1-87
Component Locations.... .5-11 Condenser
Component Views.......... .5-12 Replacement
Connector End Views.... .5-15 HVAC with A/C -
Manual.............................1-124
Schematic Control Assemble
.5-7 Description
Icons..........................
.5-7 HVAC with A/C -
References................. Manual.............................1-171
.5-8 Control Assembly
Schematics.....................
Bumpers Replacement
Specifications HVAC with A/C Manual.............................1-146
-
Fastener Tightening. .8-373 Replacement (Non-A/C) .....................................1-19

Bushing Replacement, Rear Spring. ...3-71 Conversion Table
English/Metric........................................................0-3
Coolant
C Description..........................................................6-41
Engine Coolant Temperature Sensor
Cab Replacement (Engine Cooling)..................6-32
Tilting...............................................................0-27
Camber Adjustment, Front .....................................3-20 Level Sensor Replacement
Caster Adjustment, Front........................................3-17 (Engine Cooling)
........................................6-31
Center Bearing Replacement Recovery Pipe Replacement
Propeller (Engine Cooling)
Shaft....................................................4-54 ........................................6-14
Cleaning Tape Head and Capstan, Cassette Recovery Reservoir Replacement
Cleaning (Engine Cooling)
...................................................8-138 ........................................6-13
Clearance Lamps....................................................8-94 Corrosion
Repair...................................................8-461 /
Clearcoat Repair w/o Repainting .........................8-460 Cross Channel Replacement
Clearcoat Thickness .............................................8-462 Air 3-118
Suspension.................................................
Clutch Crossmember
Clutch Pressure Plate and Clutch Replacement.....................................................8-473
Driven Plate Replacement.........................7-45
Description
Clutch Driven Members D
.................................7-48
Clutch Driving Daytime Running Lamps
Members.................................7-48
Clutch Operating Relay Replacement............................................8-95
Members............................7-48
Hydraulic Clutch
.............................................7-48 Decimal and Metric Equivalents...............................0-3
Diagnosis 5
Defective Scan
Grabbing Tool.....................................................
(Chattering).....................................7-44 Definition of Caution, Notice, and Important.............. 3
Noisy...............................................................7-44 Diagnosis
Noisy During Strategy Based
Engagement.............................7-44 Diagnosis..................................0-32
Rattle (Trans Click) Differential
........................................7-44
Slipping...........................................................7-44 Replacement
Release Bearing Replacement ..........................7-46 Rear Drive Axle..............................................4-70
Specifications Disc Brakes
Fastener Tightening........................................7-43 Burnishing Pads and
Rotors..............................5-51
Sealers and Lubricants..................................7-43
Clutch
Description................................................ 5-86, 5-87
Dust...................................................................4 Diagnosis
Coding Keys and Lock Brake Rotor Lateral Runout Check...............5-42
Cylinders...........................0-26
Collision Brake Rotor Thickness Variation Check.......5-42
Repair.....................................................8-485
Compressor Brake Rotor Tolerance...................................5-43
Compressor and Assembly Hose Assembly Specifications
HVAC with A/C -
Brake Lathe....................................................5-41
Manual.............................1-108
Description
Component.....................................................5-41
HVAC with A/C -
Fastener Tightening .......................................5-41

Manual.............................1-171
Magnetic Clutch Dome Lamp Replacement......................................8-96
HVAC with A/C -
Doors
Manual.......1-101, 1-102, 1-103, 1-104, 1-105 Description
Overhaul Assembly Mirrors
HVAC with A/C -
Heated Mirror Circuit ...............................8-429
Manual.............................1-108
Replacement Power Windows
HVAC with A/C -
Circuit Description....................................8-429
Manual...............................1-96
1998 -
MD-tsuzu
Diagnosis
Any Window Inoperative From LH Electronic Brake Control Module
Window Switch........................................ 8-409 Replacement (Air ABS) ...........................5-448
Heated Mirror System Check..................... 8-407 Engine Cooling
Mirrors Description
Heated Side Mirrors Always On............. 8-412 Air Baffles and
Seals.....................................6-41
Heated Side Mirrors Coolant...........................................................6-41
8-411 Cooling
Inoperative............................... 8-410, System..............................................6-39
Power Windows System Check.................. 8-407 Engine Oil Cooler...........................................6-40
RH Window Inoperative from Both Radiator Assembly............................... 6-39, 6-40
Switches 8-407 Transmission/Transaxle Oil Cooler................6-40
.................................................. Diagnosis
Door Replacement........................................... 8-414
Door Trim Panel Replacement........................ 8-413 Coolant Concentration Testing.........................6-7
Cooling System Leak
Door Window Testing..........................6-8
Fan
Replacement................................................ 8-423 Clutch........................................................6-6
Loss of Coolant................................................6-4
Inner Lower Window Replacement................. 8-425
Inside Door Handle Replacement................... 8-417 Overheating......................................................6-4
Mirrors Thermostat........................................................6-6
Special Tools
Replacement................................................ 8-427 Specifications
......................................................6-42
Outer Lower Window Replacement
................
8-426
Outside Door Handle Replacement................ 8-415 Fastener Tightening .........................................6-3
Specifications Engine Cooling
Power Door Systems Components................. 8-402 System................6-3
Engine Electircal
Power Door Systems Component Views ....... 8-403
Starting and Charging Connector
Power Door Systems Connector
End
End Views..................................................6-53
Views............................................... 8-406 Engine Electric
Schematic
Specifications
Outside 8-399
Mirrors............................................ Fastener Tightening .......................................6-43
Power Door Systems Schematic
Engine Electrical
References.............................................. 8-399
Schematic
Power Windows........................................... 8-399 Starting and Charging
Special 8-430 Icons..........................6-45
Tools.................................................... Starting and Charging Component Views.........6-48
Specifications Description
Fastener Tightening..................................... 8-399
Window Handle Replacement......................... 8-422 Battery..........................................................6-105
Charging
Window Regulator System..........................................6-108
Charging System
Assembly 8-422 Circuit..............................6-109
..........................................8-421, Starting
Window Run Channel Replacement............... 8-424 System............................................6-106
Starting System
Draining and Filling Cooling System Circuit................................6-108
Starting System
(Engine Cooling)..................................... .6-10 Operation............... 6-106, 6-107
Diagnosis
Driveline Battery Electrical Drain/Parasitic Load..........6-65
Angle Adjustment Battery Is Undercharged or Overcharged..... 6-67
Propeller Shaft............................................. ....4-8 Charge Indicator Always On..........................6-68
DTC C0221 5-330
.......................................................... Charge Indicator Inoperative .........................6-68
DTC C0222 5-333 Charging System
DTC
.............
5-336 Check...................... 6-56, 6-57
C0223............. Common Causes of Battery
DTC 5-339
DTC
C0225.............
5-342 Failure..................................... 6-63, 6-64, 6-65
C0226............. Generator Electrical Test ...............................6-70
DTC C0227............. 5-345 Noisy
DTC C0231 Generator.............................................6-70
.............
5-348 Starter Motor
DTC C0232 5-351
Noise........................................6-62
............. Starter Motor Relay Test................................6-63
DTC C0233 5-354 Starter No Load
............. Test.....................................6-62
DTC C0235 5-357 Starter Solenoid Clicks, Engine
.............
DTC C0236 5-360 Does Not Crank.........................................6-61
.............
DTC C0237............. 5-363 Starter Solenoid Does Not Click...................6-58
DTC C0238 5-366 Starting System
............. Check..................................6-55
DTC C0241-C0258, 5-368 Schematic
DTC C0265/C0266, 5-370 Starting and
Charging....................................6-45
DTC C0267/C0268, 5-372 Starting and Charging References................6-45
DTC C0269/C0274, 5-375 Special 6-110
Tools.....................................................
DTC C0271-C0273, 5-377 Specifications
DTC 5-378 Battery Usage Table ......................................6-44
C0279.............
DTC C0281 ,5-380 General...........................................................6-43
.............
DTC C0286............. ,5-383 Generator Usage Table..................................6-44
1998 -
MD-ISUZU
6 INDEX
Engine Exhaust
Accelerator Pedal Switch Replacement...........6-141
Clutch Pedal Switch Replacement...................6-142 Fan
Description Replacement (Engine Cooling)................6-19, 6-20
Exhaust Brake Operation.............................6-150 Shroud Replacement (Engine Cooling).............6-32
Exhaust System Fastener Notice............................................................ 5
...........................................6-150 Flexible Plastic Part
Diagnosis
Exhaust Noise..............................................6-137 Refinishing........................................................8-453
Flushing (Engine Cooling)
Restricted Exhaust ......................................6-10
.......................................6-137 Frame
Vibration or Rattling
.....................................6-137
Exhaust Clamps Replacement.............6-140, 6-141 Repair................................................................8-468
Muffler Straightening.....................................................8-467
Replacement.........................................6-147 Frame and Underbody
Pipe
Replacement................................6-145, 6-146 Description
Specifications Minimizing Frame
Service............................8-484
Welding.........................................................8-483
System Replacement.......................................6-140 Descrption
Tail Pipe
Replacement......................................6-149 General.........................................................8-483
Engine Exhaust Brake Diagnosis
Diagnosis Checking Frame Alignment
..............................................6-138, 6-139 .........................8-464
Engine Exhaust Brake Actuator Frame
...........................................................8-465
Control Valve Replacement......... 6-142, 6-144 Frame Conditions.........................................8-466
Engine Exhaust Brake Actuator Stop Specifications
Peg
Replacement....................................6-144 Electrode Chart............................................8-463
Engine Exhaust Brake Ball Joint Fastener Tightening .....................................8-463
Replacement Plug Weld
............................................6-144 Chart...........................................8-463
Engine Identification..................................................0-8 Welding
Chart...............................................8-463
English/Metric Conversion Table Yeild Strength of Different Metals
..............................0-3 ...............8-463
Entertainment Front Bumper
Component Locations.......................................8-125 Replacement.....................................................8-373
Front Suspension
Component Views.............................................8-126
Description
Connector End Views.......................................8-128
Description General...........................................................3-61
Diagnosis
Radio/Audio
System.....................................8-141 Wheel Bearing
Radio/Audio System Circuit.........................8-142 Test........................................3-25
Special Tools
Radio/Audio System Operation....................8-141 ......................................................3-62
Specifications
Diagnosis
Fastener Tightening.......................................3-25
Antenna System Test...................................8-131 Fuel and EVAP Pipe
General Radio Noise....................................8-130 ...................................................4
Fuel Pipe
No Display, No Sound from Speakers........8-129 Fitting..........................................................^
Fuel 5
Pressure...............................................................
One or More Speakers Fuel
Storage................................................................4
Inoperative.................................... 8-134, 8-135
Radio Always On
.........................................8-129
Radio Memory Inoperative...........................8-129 G
Tape Player Inoperative...............................8-130 Garnish Molding Replacement
Schematic Side Door
Upper......................... .8-447
Icons.............................................................8-123 Gasoline/Gasoline Vapors...............
Radio/Audio ........4
System.....................................8-123 Generator
References....................................................8-123 Bracket Replacement
Evaporator (Engine Electrical)............... .6-91, 6-92
Core Replacement Overhaul (Engine Electrical)....... ...........6-95
HVAC with A/C -
Replacement (Engine Electrical).

Manual.............................1-135 ...........6-92
Description Grille
Replacement.......................... .........8-361
HVAC with A/C -
Ground Strap
Manual.............................1-170
Heater/Evaporator Module Assembly Replacement (Engine Electrical). .6-90
Replacement (A/C Manual)...................1-134
-
Hose Assembly Replacement

HVAC with A/C -
1-111 H
Manual.............................
Exterior Trim Handling Electrostatic Discharge (ESD)
Cleaning Bright Metal Parts.............................8-362 Sensitive Parts
............................
Emblem/Nameplate Replacement....................8-361 Headlamp
Foreign Material Deposit Removal Aiming Procedure .8-93
..................8-362 ................................
Washing and Waxing........................................8-362 Headlamp Replacement .8-91
..........................
1998 -
MD-lsuzu
INDEX
Heater HVAC (cont.)

Core Replacement (Non-A/C)..................1-45, 1-47 Component Views
Description HVAC with A/C -
Manual...................
Controls Connector End Views
(Non-A/C).........................................1-53
Diagnosis HVAC with A/C -
Manual...................
Heat Excessive (A/C Manual).....................1-93
-
Schematic Icons
Heating Insufficient (A/C Manual)...............1-92
-
HVAC with A/C -
Manual...................
Heater/Evaporator Module Assembly HVAC Blower
Replacement (A/C Manual)...................1-134
-
Control Schematic
System Description (Non-A/C) HVAC with A/C
...........................1-52
-
Manual...................
Heater and Ventilation (Non-A/C) HVAC Compressor
Description Control Schematic
Air Distribution HVAC with A/C
System...................................1-53
-
Manual...................
Heater and Ventiliation (Non-A/C) HVAC with A/C Manual -
Description Description
Heater System................................................1-52 Maintaining Chemical Stability...........
Heater Blower Controls Diagnosis
Component Locations...........................................1-6 A/C Compressor Clutch Does Not
Component Views (Non-A/C)...............................1-7
Disengage......................................
Connector End Views (Non-A/C)....................... 1-12 Improper Air Delivery.........................
Schematic HVAC with A/C Manual -
Schematic Reference (Non-A/C) .....................1-3 Compressor Replacement......................

Schematics (Non-A/C)..........................................1-3 Compressor Sealing Washers
Heater Pipes Replacement Replacement
(A/C ..................................
Manual).............................1-143, 1-144 Description
-
Heater System Description ACR4 Procedures..............................

HVAC with A/C -
Manual.................................1-168 Compressor/Condenser Fan Ciruit....

Heater/Vent Manual A/C Circuit.............................
Module Replacement (Non-A/C) ........................1-50 Operating
(Heating and Ventilation (Non-A/C) Modes................................
Relays and Switches.........................
\ Description
System Controls.................................
Controls...........................................................1-53 Ventilation...........................................
Operating Diagnosis
Modes............................................1-54
Diagnosis A/C Compressor Clutch Does
Excessive Heat...............................................1-18
Not Engage
Insufficient Heating or Defrosting ....................................
..................1-17 Blower Control System Check
Height Leveling Valve Replacement
(Manual A/C)
..................................
Air
Suspension......................................3-126, 3-127 Condenser Fan Inoperative ...............
Hood Latch Replacement.....................................8-378
Functional
Hood Replacement...............................................8-378 Check................................
Heat Excessive...................................
Horn Heating
Insufficient.............................
Replacement.........................................8-359, 8-360 Insufficient
Horns Cooling.............................
Leak Testing
Component Locations.......................................8-353 .......................................
Refrigerant System Checks ...............
Component Views.............................................8-353
Odor Correction
Connector End Views.......................................8-357 ......................................
Description
0-Ring Replacement..............................
Refrigerant
Recovery..............................
Circuit............................................................8-360 Special Tools
Diagnosis ..........................................
Specifications
Horns Inoperative............................. 8-357, 8-358
Horns on at All Times..................................8-358 Compressor ........................................
Schematic Fastener Tightening...........................
Refrigerant Oil Distribution.................
References....................................................8-351
Systems Capacities............................
Schematics........................................................8-351 HVAC with A/C -Manual
Specifications
Diagnosis
How to Obtain Replacement Labels......................0-17 System Performance Test..................
How to Use Diagnostic Tables.............................8-150 HVAC with A/C Manual
How to Use the Paper Version of the Diagnosis
Service Manual ............................................0-4 Condenser Fan On at All Times.......
Hub Cap, Adding Lubricant....................................3-45 Hydraulic Brake Booster Replacement
......
Hub Cap Replacement, Front................................3-44 Hydraulic Brakes
HVAC Description
Component Locations Brake Warning System Circuit...........
HVAC with A/C Manual...............................1-65
-
Hydraulic Brake Booster Description.
7998 -
MD-lsuzu
8 INDEX
Hydraulic Brakes (cont.) Instrument Panel, Gauges and Console (cont.)

Diagnosis Engine Coolant Temperature Gauge
AUX BRAKE Indicator and Alarm Always Indicates Cold............................. 8-309
On w/Engine Running...................... ..........5-17 Engine Coolant Temperature Gauge
AUX BRAKE Indicator Inoperative...... ..........5-18 Inaccurate/Inoperative............................., 8-310
Brake Fluid Engine Oil Pressure Gauge Always
Leaks................................ ..........5-20
Brake Pedal Excessive Effort to Stop. ..........5-20 Indicates High Press................................ 8-311
Brake Pedal Excessive Effort with Engine Oil Pressure Gauge Always
Indicates Low Press 8-312
Off........................................ 5-19, 5-20
Engine
................................
Brake Engine Oil Pressure Gauge
System....................................... ..........5-19
Brake Warning Indicator Inoperative... ..........5-16 Innacurate/lnoperative.............................. 8-312
EH Pump and Booster Mating Fasten Safety Belt Indicator
Surface Fluid Always 8-324
Leak........................... ..........5-21 On...............................................,
EH Pump End Plate Oil Leak Fasten Safety Belt Indicator
............. ..........5-21
EH Pump Motor Oil
Leak.................... ..........5-21 Inoperative................................................ 8-324
EH Pump Fuel Gauge Always Indicates
Noise................................... ..........5-21
External Conditions that Affect Brake
Empty........................................... 8-313, 8-314
Fuel Gauge Always Indicates
Performance..................................... ..........5-19
Hydraulic Booster 8-316
Noise...................... ..........5-22 Full................................................8-315,
Hydraulic System Fluid Fuel Gauge Innacurate or
Loss............... ..........5-21
Master Cylinder Diagnosis................... ..........5-21 Inoperative........................ 8-317, 8-318, 8-319
Electrohydraulic Pump Replacement....... ..........5-37 Low Engine Coolant Indicator
Front Brake Hose Replacement.............. ..........5-29 Always 8-324
ON..............................................
ISO Flares Low Engine Coolant Indicator
Replacement.......................... ..........5-28
Master Cylinder Hose Replacement........ 5-26, 5-27 Inoperative.................................... 8-325, 8-326
Pipe Speedometer and/or Odometer
Replacement.................................... ..........5-25
Rear Brake Hose Replacement............... ..........5-30 Inoperative............................................... 8-327
Special
Tools............................................. ..........5-40 Tachometer Inoperative............................... 8-328
Specifications Voltmeter Inaccurate or Inoperative........... 8-322/
Fastener Tightening.............................. ............5-7 Instrument Cluster Component Views............ 8-29?i
System Bleeding. .5-32, 5-33 Instrument Cluster Connector End Views...... 8-303
System Flushing. ...........5-34 Schematic
Audible Warnings Schematic
el-328
References..............................................
Audible Warnings
Schematics..................... 3-328
Instrument Cluster Analog........................... :8-283
Identification Instrument Cluster Schematic Icons........... :8-283
.............0-8
Engine.............................................................. Instrument Cluster Schematic
Rear Axle.........................................................
.............0-9 8-283
References..............................................
Specifications
Transmission....................................................
.............0-8
.............0-5
Vehicle.............................................................. Fastener Tightening.................................... 8-283
Ignition OFF When Disconnecting Interior Trim
Battery.........
................5
Ignition Switch Replacement Basic Steps Before Cleaning.......................... 8-451
...........2-65
(Tilt).......................
Instrument Cluster Cargo Area Trim
Description Rear Panel Replacement............................ 8-442
.........8-346 Cleaning 8-450
Circuit........................................................... Agents..............................................
Instrument Panel Cleaning Glass 8-451
Surfaces.................................
Cleaning Vinyl Trim
Carrier.............................................................. 8-340 .........................................
8-450
Cluster Replacement ............................8-337, 8-338 Door Sill Plate
Lamp Replacement.......................................... ..8-96
Replacement................................................ 8-442
Instrument Panel, Gauges and Console Front Floor Mat/Carpet Replacement............. 8-441
Audible Warnings Component Locations........ 8-330 Headliner Replacement................................... 8-443
Audible Warnings Component 8-331
Cleaning.............................................. 8-451
Views.............. Interior
Audible Warnings Connector End Views........ 8-333 Overhead Console Replacement.................... 8-444
Component Locations...................................... ,8-291 Quarter Trim Panel Replacement 8-449
Description ...................
Rear Window
Audible Warnings 8-350 Upper Molding Replacement...................... 8-448
Circuit.............................
Audible Warnings Operation
.......................
8-347 Removal Of Specific Stains............................ 8-451
Diagnosis Seat Belt
All
Care................................................. 8-452
Gauges Inoperative................................ Spot Cleaning Fabric
Trim.............................. 8-450
,8-321
Audible Warnings Diagnostic Sunshade
System Check......................................... 8-334 Replacement................................................ 8-446
Check Gauge Indicator Always ,8-322 Windshield Pillar Garnish Molding
On............
Check Gauge Indicator Inoperative............ 8-323 Replacement........................................... 8-446
1998 -
MD-lsuzu
INDEX 9
Lighting Systems (cont.)

J
Interior Lights System Check
Jacking and Lifting. ........................8-50
.0-26 IP Turn Signal Indicators
Inoperative............8-87
Left High Beam Headlamp Inoperative.........8-61
K Left Low Beam Headlamp Inoperative..........8-55
LF Park Lamp
Key Coding and Lock Cylinders Inoperative.............................8-69
............................0-26 LF Turn Signal
King Pin and Steering Knuckle Replacement Inoperative............................8-81
.......3-27 LH IP Turn Signal Indicator Inoperative
King Pin Bearing .......8-87
Preload.......................................3-57 License and Tail Lamps
King Pin Bushing and Bearing Cup
Inoperative........................................ 8-66, 8-67
Replacement..............................................3-49 Lighted Outside Rearview
King Pin Upper Bearing
Repack............................3-52 Mirror Lamps Inoperative....... 8-71, 8-72, 8-73
Low Beam Headlamps On with
Headlamp Switch Off....................... 8-59, 8-60
LR Turn Signal Lamp
Label Inoperative.................8-85
No LH Turn Signal Output at
Service Parts .0-11 Trailer Connector
ID........................... .......................................8-88
Labels, Replacement No RH Turn Signal Output at
How to Obtain............................... .0-17 Trailer Connector
Leaf Spring Replacement, Rear....... .3-74 .......................................8-89
One Headlamp Inoperative............................8-63
Leaf Springs Replacement, Front.... .3-33 One Side Marker Lamp Inoperative....8-73, 8-74
Lifting and .0-26
Jacking............................ Park, Side Marker, and Clearance Lamps
Lighter
Always On..................................................8-70
Cigar Lighter Replacement
..............................8-339 Park, Side Marker, and Clearance-
Lighting Systems
Lamps Inoperative
Component Locations.........................................8-19 .....................................8-70
Rear Turn Signal Lamps Inoperative............8-85
Component Views...............................................8-22 RF Park Lamp Inoperative
Connector End Views.........................................8-43 ............................8-69
RF Turn Signal Lamp Inoperative.................8-83
Description Right High Beam Headlamp Inoperative
........................................................8-100 ......8-61
Backup Lights Circuit...................................8-101 Right Low Beam Headlamp Inoperative....... 8-55
DaytimeRunning Lamps Circuit...................8-100 RR Turn Signal Lamp Inoperative.................8-86
Exterior Lights Circuit...................................8-100 Stoplamps Always
On.......................... 8-76, 8-77
,,
Interior
Lights................................................8-101 Stoplamps Inoperative
Interior Lights Dimming Circuit ....................8-101 ...................................8-80
RH IP Turn Signal Indicator Inoperative...........8-88
Diagnosis Special Tools
All IP Lamps ....................................................8-102
Inoperative.....................8-64, 8-66 Specifications
All Park, Side, and Front Marker
Fastener Tightening .........................................8-7
Lamps Inoperative......................................8-70 Lock Cylinder
All Side Marker Lamps Replacement..................................8-420
Inoperative...............8-74 Lock Cylinders and Key Coding
All Stoplamps ............................0-26
Inoperative....................8-78, 8-79 Lock Replacement
Backup Lamps Inoperative ............................8-51
Backup Lights System Check........................8-50 Door..................................................................8-418
Lock System
Both High Beam Headlamps Inoperative......8-62 Diagnosis
Both Low Beam Headlamps
System Sticks in Start
Inoperative........................................8-56, 8-57 Tilt
Wheel/Column.....................................^^
Clearance Lamps Inoperative........................8-52 Lubricant Change
Courtesy Lamp or Dome Lamp Rear Drive Axle ..................................................4-68
Inoperative..................................................8-52
Daytime Running Lamps Always On ............8-53
Daytime Running Lamps Indicator M
Inoperative..................................................8-53
Daytime Running Lamps On With Main Support
Engine Not Running ..................................8-63 Beam Repair
Suspension............................................. 3-113
Daytime Running Lamps System Check ......8-50 Air
Dome Lamp Inoperative When Maintenance and Lubrication
LH Door is Open Explanation of Scheduled Services...................0-47
.......................................8-54
Exterior Lights System Check.......................8-50 Inspections and Other Services.........................0-50
Flash to Pass Inoperative..............................8-63 Long Trip/Highway Maintenance Schedule.......0-43
Front Parking Lamps Inoperative..................8-68 Manitenance Schedule.......................................0-35
Front Turn Signal Lamps Inoperative............8-81 Owner Checks and Services................... 0-43, 0-46
Front Turn Signals and IP Indicators Short Trip/City Maintenance Schedule..............0-43
Specifications
Inoperative..................................................8-84
Hazard Lamps Inoperative.............................8-55 Approximate Fluid Capacities........................0-33
High Beam Indicator Inoperative...................8-64 Maintenance Items.........................................0-34
Interior Lights Dimming System Check.........8-50 Recommended Fluids and Lubricants...........0-34
7998 -
MD-lsuzu
10 INDEX
Manual Transmission Park Brake (cont.)

Description and Operation Shoe Adjustment................................................5-94
.................................7-14
Diagnosis Shoe Inspection..................................................5-93
Jumps Out of Gear..........................................7-3 Shoe Replacement................................... 5-89, 5-90
Manual Transmission .......................................7-3 Specifications
Noisy
Bearings.................................................7-4 Fastener Tightening .......................................5-89
Noisy in All Support
Gears............................................7-5 Replacement.......................................5-106
Noisy in Neutral with Engine Running Warning Lamp Switch Replacement..................5-98
............7-5
Noisy in the Parking/Turn Signal
Gears...........................................7-4
Oil Lamps Replacement...........................................8-94
Leak............................................................7-4
Sticking in Pinion
Gear................................................7-4
Oil Change Drive Pinion Yoke Replacement
Procedure..........................................7-9
Replacement.......................................................7-12 Rear Drive Axle..............................................4-74
Specifications Pitman Arm Replacement.......................................2-59
Fastener Tightening..........................................7-3 Power Steering
Lubrication Bleeding the System
........................................................7-3 ..........................................2-27
Marker Lamp Replacement, Side...........................8-93 Description
Master Cylinder Power Steering System.................................2-51
Bench Bleeding...................................................5-24 Diagnosis
Fluid Level Sensor
Replacement.......................5-24 Excessive Wheel Kickback or
Loose Steering.............................................2-5
Replacement.......................................................5-23
Reservoir Filling..................................................5-22 Foaming, Milky-Appearing PS Fluid,
Meanings of Abbreviations .....................................0-23 Low in
Level.................................................2-7
Mode Actuator Increase in Effort While Turning
Replacement (A/C Manual) ...........................1-149
-
Steering Wheel ............................................2-6
Mode Valve Low Oil Pressure Due to Restriction
Actuator Replacement (Non-A/C).......................1-37 in the Hose
..................................................2-7
Modulator Valve Replacement (Air ABS) Low Oil Pressure Due to Steering Gear.........2-7
Low Oil Pressure Due to Steering Pump.......2-6
Front..................................................................5-449
Noise
Rear...................................................................5-448
Moving Parts and Hot Groan in Steering Pump.............................2-8
Surfaces..................................4
Multifunction Alarm Module Replacement............8-345 Growl in Steering Pump...................... 2-8, ?--9
Objectionable
Hiss...................................... 2-5
Rattle or Chuckle in Steering
N Rattle or Knock in Steering
Gear............2-5
Pump..............2-9
Nylon Fuel Swish in Steering
Lines........................ ..................................5 Pump..............................2-9
Whine in Steering
Pump..............................2-9
Poor Return of Steering Wheel.......................2-6
0 Steering Effort Hard in Both Directions ..........2-6
Ordering Information System Test Procedure....................................2-3
Special Vehicle Leads to One Side or the Other........2-7
Tools.......................... ...............................0-5
Outside Mirror Clearance Lamp Replacement ......8-99 Wheel Surges or Jerks While Turning............2-6
End Limiters Replacement.................................2-42
Flushing
P
Hoses..............................................................2-29
Paint/Coatings Power Steering System .................................2-28
Anti-Corrosion Treatment
.................................8-457 Gear Replacement .............................................2-34
Paint Identification............................................8-459 Hoses Replacement...........................................2-31
Sheet Metal Refinishing Input Dust Cap Replacement
............................2-37
Input Shaft Bearing Cap Replacement
Basecoat/Clearcoat..................................8-457 .............2-40
Specifications Pressure Relief Valve Replacement..................2-44
Clearcoat Repair 3M Products..................8-455
-
Pump Replacement............................................2-10
Clearcoat Repair Meguiar Products..........8-456
-
Reservior Replacement ......................................2-47
Paint Resuction Valve Replacement...........................2-46
Gauges........................................................8-462
Park Brake Sector Shaft Dust Cap Replacement......2-36, 2-37
Bellcrank and Cam Lever Replacement..........5-107 Special Tools
......................................................2-51
Brake Drum Inspection.....................................5-105 Specifications
Brake Drum Replacement....................5-101, 5-103 Fastener Tightening
.........................................2-3
Cable Inspection...............................................5-101 Power Steering Pump
Cable Replacement............................................5-99 Overhaul
Description Pump Assemble...................................2-12, 2-18
System Operation......................................... 5-112 Propeller Shaft
Lever Adjustment................................................5-98 Assembly Component Lubrication .....................4-51
Lever Replacement.............................................5-97 Description..........................................................4-60
Lubrication Procedure.........................................5-96 Center Bearing...............................................4-62
1998 -
MD-lsuzu
INDEX 11
Propeller Shaft (cont.) Rear Suspension (cont.)

Special Tools
Phasing...........................................................4-61 ......................................................3-86
Universal Specifications
Joint................................................4-61
Diagnosis Fastener Tightening .......................................3-63
Ping, Snap, or Click Rear Window
Noise..............................4-7
Roughness or Vibration
...........................4-3, 4-6 Replacement.....................................................8-369
Driveline Angle
Adjustment..................................4-8 Receiver Dehydrator and Evaporator Hose Assembly
One-Piece Propeller Shaft Replacement..........4-10, HVAC with A/C Manual -
.................................1-115
4-12, 4-14, 4-16, 4-18, 4-20, 4-22, 4-24, 4-26 Receiver Dehydrator Replacement
Special HVAC with A/C Manual -
Tools.......................................................4-62 .................................1-117
Specifications Refrigerant
Fastener Tightening..........................................4-3 Description
Three-Piece Propeller Shaft Handling of Refrigerant Lines and Fittings
Replacement .................4-40, 4-43, 4-45, 4-48 (HVAC with A/C Manual) -
......................1-169
Two-Piece Propeller Shaft R-134a
Replacement .......4-28, 4-30, 4-33, 4-35, 4-38 HVAC with A/C -
Manual.........................1-168
Proper Use of Torque Wrenches ...........................0-21 Handling R-134a
HVAC with A/C Manual.............................1-169
-

R HVAC with A/C Manual
.....................1-165, 1-167
-
Radiator Relay
Assembly Description ...............................6-39, 6-40 Steering Linkage (Non-Rack Pinion)
Cleaning (Engine Relay Rod Replacement................................2-58
Cooling).................................6-11
Hose Replacement (Engine Cooling) ......6-17, 6-18 Relay Rod Replacement.........................................2-58
Lower Mounting Panel Replacement Relief Valve Replacement, Air Suspension.........3-128
(Engine Cooling) Road 4
........................................6-36 Test.....................................................................
Replacement (Engine Cooling) ..........................6-33
Radio Replacement
..............................................8-137
Rail Dust Damage Repair
s
....................................8-462
Rear Axle Controls Safety Glasses and Compressed Air...................
Safety Goggles and Fuel.....................................
Components........................................................4-92
(Connector End Views.........................................4-93 Seat Belts
Description Center Seat Belt Replacement........................ .9-11
Two Speed Rear Axle Circuit......................4-102 Description
Two Speed Rear Axle Shift System............4-101 System Operation......................................... .9-12
Diagnosis Diagnosis
Two Speed Rear Axle Shift Motor ......4-94, 4-95 Operational and Functional Checks............ ,9-3
Two Speed Rear Axle System Check...........4-94 Driver or Passenger Seat Belt Replacement.. ....9-4
Schematic Seat Belt Service Precautions......................... ....9-3
Specifications
Icons...............................................................4-89
References......................................................4-89 Fastener Tightening..................................... ....9-3
Specifications Seat Replacement
Fastener Tightening........................................4-89 Center 8-433
...............................................................
Two Speed Rear Axle Schematics....................4-90 Seats
Two Speed Rear Axle Shift Motor Relay Diagnosis
Replacement..............................................4-97 Manual Seat

Two Speed Rear Axle Shift Motor Adjuster Between Lock Positions............ 8-431
Adjuster Does Not Lock 8-431
Replacement..............................................4-99 ..........................
Rear Axle Identification.............................................0-9 Adjuster Does Not 8-431
Unlock.......................
Rear Drive Axle Seat Replacement............................................ 8-432
Description Seat Riser Replacement...................... 8-434, 8-438
Rear Axle..............................................4-86, 4-87 Specifications
Diagnosis Fastener Tightening..................................... 8-431
Determining Type of Noise............................4-63 Service Manual
General Information........................................4-67 Description of Arrows and Symbols
................ .0-5
Noise Diagnosis.............................................4-66 General Information
Housing Replacement........................................4-82 Fasteners.................................... 0-17, 0-19
0-20
Special Thread Inserts .0-20
Tools.......................................................4-87 ..............................................
Specifications How to Use the Paper Version........................ ...0-4
Fastener Tightening........................................4-63 RPO Code List .0-11
.................................................
Rear Hub and Bearing Replacement Service Parts ID Label......................................... .0-11
Rear Drive Axle.............................. 4-77, 4-80, 4-81 Shift Cable
Rear Suspension Adjustment (Automatic AT542 Allison)............ .7-26
Diagnosis Adjustment (Manual Transmission).................. ...7-8
Spring Maintenance
.......................................3-63 Replacement (Automatic AT542 Allison)......... .7-24
1998 -
MD-lsuzu
12 INDEX
Shift Cable (cont.) Specifications (cont.)
Replacement (Manual Transmission)...................7-6 Seat
Belts.........................................................9-3
Shock Absorber
Seats.............................................................8-431
Replacement Steering Linkage (Non-Rack Pinion).............2-53
Air Suspension Tilt
.............................................3-129 Wheel/Column..........................................2-63
Shock Absorber Replacement, Front.....................3-47 Tires and
Wheels...........................................3-87
Shock Absorber Replacement, Rear Wheel Alignment............................................3-17
.....................3-70
ShopTowel Fuel Link General
...................................................4
Single Cylinder Engine Electrical.............................................6-43
Flooding..............................................5
Slip Joint Replacement Generator Usage Table
Propeller Engine Electrical.............................................6-44
Shaft....................................................4-52
Speaker Replacement..........................................8-140 Governor Valve Adjustment
Special Tools Air Compressor
............................................5-287
Antilock Brake System Lubrication
.....................................5-398
Manual Transmission
Doors.................................................................8-430 .......................................7-3
Engine Cooling Mechanical
...................................................6-42
Engine Electrical...............................................6-110 Air
Compressor............................................5-287
Front Refrigerant Oil Distribution
Suspension................................................3-62
HVAC with A/C Manual HVAC with A/C -
Manual...............................1-57
-
.................................1-176
Hydraulic Sealers and Lubricants
Brakes.................................................5-40
Lighting Systems
..............................................8-102 Clutch..............................................................7-43
Power Steering...................................................2-51 System Capacities
Propeller Shaft....................................................4-62 HVAC with A/C -
Manual...............................1-57
Rear Drive Axle ..................................................4-87 Wheel Alignment
................................................3-17
Rear Suspension................................................3-86 Speedometer Driven Gear
Stationary Backlash Adjustment
Windows..........................................8-372
Steering Linkage (Non-Rack Pinion) (Manual Transmission)...............................7-10
.................2-62
Steering Wheel/Column -
Replacement (Manual Transmission).................7-10
Tilt.............................2-78
Special Tools Ordering Splicing Inline Harness
Information..........................0-5 Diodes............................8-172
Specifications Spring /
Battery Usage Table Air Spring Frame Hanger Replacement
Air
Engine Electrical.............................................6-44 Suspension............................................. 3-117
Brake Lathe Bumper Replacement, Rear...............................3-84
Disc Brakes Bushing Replacement,
....................................................5-41 Rear.............................. 3-71
Components Hanger Bracket Insulator Replacement
Air
Suspension............................................. 3-119
Air
Drums..........................................5-227, 5-228
Disc Brakes Hanger Replacement, Rear...............................3-80
....................................................5-41
Compressor Leaf Replacement, Rear...............................i.....3-78
HVAC with A/C -
Rear Leaf Spring Replacement.........................3-74
Manual...............................1-57
Engine Cooling System Spring Bumper
Replacement.................................3-33
Engine Cooling.................................................6-3 Spring Replacement, Front
Leaf............................3-33
Fastener Tightening Stabilizer Shaft Replacement
.................................3-26
Air Stabilizer Shaft Replacement,
Brakes..................................................... 5-113 Rear.......................3-64
Air Starter
Compressor.............................................5-287
Air Motor Inspection (Engine Electrical)..................6-76
Drums......................................................5-227
Air Motor Overhaul (Engine Electrical)....................6-73
Suspension.............................................3-107
Antilock Brake Motor Relay Replacement
System.................................5-303
(Engine
Clutch..............................................................7-43 Electrical)......................................6-71
Disc Motor Replacement (Engine Electrical) .............6-71
Brakes....................................................5-41
Doors Stationary Windows
............................................................8-399
Engine Cooling.................................................6-3 Quarter Window Replacement.........................8-368
Engine Special Tools
Electrical.............................................6-43 ....................................................8-372
Engine Exhaust............................................6-137 Window Polishing.............................................8-371
Front Steering Arm Replacement ....................................2-56
Suspension...........................................3-25
Heater and Ventilation, Non-A/C.....................1-3 Steering Knuckle and King Pin Replacement.......3-27
HVAC with A/C Manual. -
.1-57 Steering Linkage

Hydraulic Brakes Description
.............. ...5-7
Lighting ...8-7 Non-Rack Pinion ............................................2-62
Systems..............
Manual Transmission ...7-3 Steering Linkage (Non-Rack Pinion)
.......
Park Brake........................ .5-89 Inspection............................................................2-53
Power Steering................. ...2-3 Pitman Arm Replacement..................................2-59
Propeller Shaft.................. ...4-3 Special Tools
......................................................2-62
Rear Axle Controls........... .4-89 Specifications
Rear Drive Axle................ .4-63 Fastener Tightening .......................................2-53
Rear Suspension.............. .3-63 Steering Arm
Replacement................................2-56
1998 -
MD-lsuzu
INDEX 13
Steering Linkage (Non-Rack Pinion) (cont.) Suspension (cont.)

Tie Rod Arm Descriptioin
Replacement.................................2-57
Tie Rod Replacement.........................................2-54
General...........................................................3-15
Steering Shaft Diagnosis
Lower Shaft Assembly Replacement (Tilt) ........2-74 Abnormal or Excessive Tire Wear...................3-3
Upper Shaft Assembly Replacement (Tilt) ........2-71 Excessive Road Shock....................................3-7
Steering Wheel/Column Tilt -
Front Wheel Shimmy
.......................................3-9
Description Hard
Steering...................................................3-9
Steering Wheel and Column Low or Uneven Trim Height..........................3-14
.........................2-77
Diagnosis Noisy Front
Suspension...................................3-6
High Steering Shaft Poor Directional Stability..................................3-7
Effort..............................2-63
Key Cannot Be Removed in the Spring
Breakage...............................................3-9
Off Lock Spring 3-8
Position........................................2-63 Noise.....................................................
Loose Steering Wheel (Every Other Spring Sags or Bottoms
..................................3-8
Tilt Struts or Shock Absorber Bench Test
Position)................................................2-64 ............3-8
Noise in Steering Column..............................2-63 Struts or Shock Absorbers Binding.................3-8
Noise When Tilting Steering Column............2-64 Struts or Shock Absorbers
Steering Wheel Does Not Lock in On-Vehicle Testing
Tilt
.......................................3-8
Any Position.........................................2-64 Suspension Bottoms ........................................3-3
Steering Wheel Not Returning to Tire Hop or Poor Handling
..............................3-7
Top Tilt Position Vehicle
.........................................2-64 Leads/Pulls..........................................3-3
Turn Signal Does Not Cancel........................2-64 Wander or Poor Steering Stability...................3-6
Lock System Sticks in Start...............................2-63 Wheel Bearings..............................................3-10
Multifunction Signal Lever Front
Replacement (Tilt) ......................................2-66 Description
Special
Tools.......................................................2-78 General.......................................................3-61
Tilt Lever Replacement Rear
......................................2-67
Steering Wheel Replacement (Tilt) ........................2-68 Description
Strategy Based Diagnostic
Flow..........................8-160 General.......................................................3-86
Striker Replacement Diagnosis
Door...................................................................8-420 Spring
Maintenance...................................3-63
Struts or Shock Absorber Switch
Diagnosis Blower Switch
Binding..............................................................3-7 Replacement.................................................1-147
Struts or Shock Absorbers Engine Oil Pressure Switch Replacement ......8-339
Diagnosis Fluid Flow Switch
Replacement.........................5-38
Bench Ignition Switch Replacement
Test........................................................3-8 (Tilt).....................2-65
Struts or Shock Absorbers Low Air Pressure Warning Switch
Diagnosis
Replacement............................................5-189
On-Vehicle Testing Pneumatic Stoplamp Switch
...........................................3-8
Surge Tank
(Diesel) Replacement (Engine Cooling) Replacement............................................5-173
............6-11 Stoplamp Switch Replacement..........................5-38
Inlet Pipe Replacement (Engine Cooling).........6-15 Trailer Stoplamp Switch Replacement.............5-174
Outlet Pipe Replacement Two Speed Rear Axle Shift Control
(Engine Cooling) Switch Replacement
........................................6-16 ..................................4-97
Suspension Wipers/Washer Switch Replacement...............8-120
Air Switch (Blower)
Air Spring Frame Hanger Replacement (Non-A/C) .....................................1-20
Replacement............................................3-117
Air Spring Replacement...............................3-130
Cross Channel Replacement.......................3-116
Description
Tail Lamp
Air Control
System...................................3-132 Replacement................................8-97, 8-98
Air Suspension Relief Valve....................3-132 Temperature Valve
Height Leveling Actuator Replacement
Valve..............................3-132
Rear Air Suspension................................3-132 HVAC with A/C -
Manual.............................1-158
Hanger Bracket Insulator Replacement ......3-119 Temp Valve Actuator
Height Leveling Valve Replacement (Non-A/C) .....................................1-33
Replacement ................................3-126, 3-127 Thermal Expansion Valve Replacement
Relief Valve Replacement............................3-128 HVAC with A/C Manual -
.................................1-119
Shock Absorber Replacement.....................3-129 Thermostat
Suspension Controls Circuit Description .....3-132 Housing Replacement (Engine Cooling)
...........6-20
Torque Rod Bushing Replacement..............3-121 Replacement (Engine Cooling)..........................6-22
Torque Rod Replacement............................3-120 Tie Rod Arm Replacement.....................................2-57
Air Transverse Rod Replacement........ 3-122, 3-124 Tie Rod Replacement.............................................2-54
1998 -
MD-lsuzu
14 INDEX
Tilting Vibration (cont.)

Correcting Driveline Vibration -
Cab......................................................................0-27
Tilt Lever RWD and
Replacement...........................................2-67 4WD..........................................0-76
Tilt Wheel/Column Correcting Non-Uniform Tires
............................0-75
Specifications Correcting Tire and Wheel Vibration.................0-71
Fastener Tightening........................................2-63 Description
Tire General Description........................................0-94
Description........................................................3-102 Diagnosis............................................................0-52
Inflation Classifying the Vibration
Description..........................................3-103 ................................0-56
Driveline Vibration Analysis w/ EVA..............0-63
Matching..............................................................3-98
Measuring Engine Related
.........................................................3-101 Vibration...............................0-67
Mounting and Dismounting Road Test.......................................................0-52
................................3-94
Repair Description............................................3-103 Systematic Approach
.....................................0-52
Tire and Wheel Vibration...............................0-59
Rotation...............................................................3-98
Valve Core and Cap Replacement..................3-102 Wheel Runout Measurement.........................0-59
Tires and Wheels General Service Precautions .............................0-71
Special Tools
Description........................................................3-102 ....................................................0-105
Specifications
Inflation.........................................................3-103
Load Range/Ply Rating................................3-105 Vibration Diagnosis
........................................0-51
Wheel Weight Usage
Repair...........................................................3-103 .........................................0-75
Vehicle Certification Label............................3-105 VI N
VIN
Wheels..........................................................3-105 Derivative.......................................................0-6
Diagnosis
Hub Bolt and W
Nut.................................3-87, 3-88
Rim/Hub Bolt
Check.......................................3-88
Wheel Mounting Surface Check....................3-87 Washer Pump/Reservoir Replacement................ 8-114
Specifications Waterleaks
Fastener Tightening........................................3-87 Diagnosis
Wheel Installation Air Hose
.....................................3-91, 3-92 Test
Test................................................8-364
Wheel Removal Preparation...........................................8-36^
..................................................3-90
Toe Adjustment, Front Water Hose Test..........................................8-364
............................................3-21
Torque Rod Generalized Testing..........................................8-363
Bushing Replacement Stationary Window Waterleak Repair.............. 8-'364
Air Water Pump
Suspension.............................................3-121
Replacement Overhaul (Engine Cooling).................................6-26
Air Suspension Replacement (Engine Cooling)..........................6-23
.............................................3-120 Wheel
Torque Wrenches
Proper Use..........................................................0-21 Installation
Tow Hook Replacement........................................8-480 Tires and Wheels................................. 3-91, 3-92
Towing Removal
Disabled Tires and Wheels
Vehicle.................................................0-30 ...........................................3-90
Transmission Wheel Alignment
Description
Replacement (Automatic AT542 Allison) ...........7-30
Transmission Identification........................................0-8 Camber............................................. ...........3-23
Transverse Rod Caster............................................... ...........3-23
Replacement Frame Misalignment......................... ...........3-24
Air Suspension General
.................................3-122, 3-124 .............................................
Steering Axis Inclination..................
...........3-23
...........3-24
Toe ...........3-23
....................................................
u Front Camber Adjustment.................... ...........3-20
Front Caster Adjustment ...........3-17
Universal Joints Replacement ......................
Front Toe Adjustment........................... ...........3-21
Propeller
Shaft....................................................4-58 Specifications........................................ ...........3-17
Fastener Tightening......................... ...........3-17
Stop Screw
v Adjustment........................ .3-21, 3-22
Wheel Bearing Adjustment
Valve Core and Cap Replacement. .3-102 Rear Drive Axle .4-84
....................................
Vehicle Certification Label............... .....0-7 Wheel Bearing Adjustment, Front............ .3-45
Vehicle Identification........................ .....0-5 Wheel Hub, Bearing, Knuckle, and Seal
Vehicle Replacement, Front.........................3-36, 3-40
Lifting................................... ........4
Vent Hose Wheel Hub Bolt Replacement
Replacement Rear Drive Axle............................ .4-86
Rear Drive Axle....................... .4-76 Wheels
Vibration
Description........................................................3-105
Balancing Tires and Wheels....... .0-71 Window Removal......................................................... 4
1998 -
MD-lsuzu
INDEX
Windshield Wiring Systems (cont.)
Replacement.....................................................8-366 How to Use Circuit Descriptions
.................
Upper Reveal Molding Replacement...............8-365 How to Use Component
Wiper Arm Blade Replacement............................8-116 Location
Tables........................................
Wiper Arm Replacement...................................... 8-116 How to Use Component
Wiper Center Pivot Replacement.........................8-117 Location
Views.........................................
Wiper Chatter Repair............................................8-120 How to Use Connector End Views.............
Wiper Motor Replacement.................................... 8-118 How to Use Diagnostic
Wipers/Washer Systems System
Checks........................................
Component Locations.......................................8-105 How to Use Electrical Diagnosis.................
Component Views.............................................8-106 How to Use Electrical Schematics
..............
Connector End Views.......................................8-108 How to Use Schematic Icon Table..............
Description How to Use Schematic
Circuit............................................................8-121 Reference Tables.....................................
System Operation.........................................8-121 Scan Tool Does Not Communicate
Windshield Wipers/Washer System.............8-121
w/Components............................. 8-227,
Diagnosis Symptom Diagnostic
Example.....................
System Check..............................................8-109 Terminal Position Assurance Locks.............
Washer Does Not Shut Off.......................... 8-113 Testing for Continuity
...................................
Washer Pump Inoperative............................8-112 Testing for Electrical Intermittents
...............
Windshield Wiper Motor Inoperative Testing for Poor Connections
......................
(All Testing for Short to
Modes)...............................................8-110 Ground.........................
Windshield Wiper Operates Only in Testing for
Voltage.......................................
High Speed, Low Speed Inoperative...... 8-111 Troubleshooting with a
Wiper Arm Tip Pressure Check, Digital
Multimeter.....................................
Blade Element Check..............................8-114 Troubleshooting with a Short
Finder...........
Wiper Does Not Shut Off............................. 8-111 Troubleshooting with a Test
Light...............
Wiper Operates Only in Low Upfitter Provision Relay
Inoperative............
Speed, High .............................................8-110 Using Connector Test
Adapters...................
Wipers and Washer Inoperative..................8-109 Using Fused Jumper
Wires.........................
Schematic Where to Find Electrical Schematics..........
Wiring
References....................................................8-103 Repairs..............................................
Schematics (Pulse)...........................................8-103 Power and Grounding Components................
Wiper Transmission Replacement........................8-119 Power and Grounding Component Views.......
Wiper/Washer Switch Replacement.....................8-120 Power and Grounding Connector
Wiring Systems End
Views................................................
Data Link Connector (DLC) Components........8-226 Schematics
Data Link Connector (DLC) Data Link Connector (DLC)
Component Views ....................................8-226 Schematic
Icons.......................................
Data Link Connector (DLC) End Views...........8-227 Data Link Connector (DLC)
Description Schematic References.............................
Data Link Connector (DLC).........................8-229 Data Link Connector (DLC)
Data Link Connector (DLC) Circuit .............8-229
Schematics...............................................
Data Link Connector (DLC) Operation........ 8-229 Fuse Block Details.......................................
Harness Routing Views................................8-258 Ground Distribution......................................
Inline Harness Connector End Views .........8-230 Power and Grounding Schematic Icons .....
Diagnosis 8-172
.................................. 8-150, 8-160, Power and Grounding Schematic
Checking Aftermarket Accessories..............8-162
References...............................................
Cigar Lighter Power Distribution
Inoperative..............................8-222 ........................................
Connector Position Assurance Locks..........8-174 Upfitter
Provision..........................................
Connector Repairs .......................................8-173 Specifications
Data Link Connector (DLC) Fastener Tightening.....................................
System Check..........................................8-227 Work Stall
Test......................................................
Electrical
Symbols........................................8-151
General Electrical Diagnosis
Procedures...............................................8-156
H02S Wiring Repairs...................................8-173
Y
Yoke Replacement
Propeller Shaft...
1998 -
MD-lsuzu
16 INDEX
BLANK
4
;c
1998 -
MD-lsuzu

FS198 WSM C01 - 1

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What is the purpose of the service manual?

What is the purpose of the service manual?

What are the main sections of the new service manual structure?

What are the main sections of the new service manual structure?

CAUTION

Heating, Ventilation, and HVAC systems with Air

6, 6A Engine Mechanical 6 Engine Engine Mechanical

end of the manual

ISUZU MOTORS AMERICA, INC.

1998 ISUZU MOTORS AMERICA, INC. ALL RIGHTS RESERVED

Rear Drive Axle..........................

Restraints...............................................................9-1 Engine, On-vehicle Service ................

Cautions and Notices..........................................3 Safety Glasses and Compressed

Cautions and Notices

and Important characteristic of

component, the ignition key must be in the OFF

system or component under repair

Brake Fluid Caution During normal operation, the 0-rings located in

Fuel Pipe Fitting Caution Window Removal Caution

Work Stall Test Caution Handling ESD Sensitive Parts Notice

Do not exceed 56 km/h (35 mph) when

Avoid the following actions unless required by the

rotors removed. Ignition OFF When Disconnecting

connecting or disconnecting battery cables, battery

General Information..........................................o-3 Maintenance ......................................................0-35

How to Use..................................................0-4 Long Trip/Highway

cu yd 0.7646 cu m 1/16 0.0625 1.5875

TORQUE 1/4 0.25 6.35

hp 0.746 kW 5/16 0.3125 7.9375

Fraction (in) Decimal (in) Metric (mm) How to Use

49/64 0.765625 19.44687 3. Repair procedures

Arrows and Symbols Special Tools Ordering Information

0 ^ Mon.-Fri. 8:00 a.m. to 7:00 p.m. EST

The VIN plate is attached to the driver's door

Vehicle Identification Number (VIN) System

12-17 Plant Sequence Number

Incomplete Vehicle Certification Label

6VWR-IB/KQ QAWR FRT QAWB INT OAWH RR

The payload rating shown on the label is the

The Allison transmission identification plate is

The Isuzu transmission identification plate is located

Rear Axle Identification

All axle housings have identification tags or

Eaton Differential Carrier ID

The housing tag is the same type of tag used for

BAG Parts Package Export

First Position Prop Hanger, NON-BOC,

First Position Prop Hanger, NON-BOC,

EH8 432 cm (170 in) Wheelbase

The Vehicle Identification Number (VIN) EV9 Suspension: Attach Bolted

All production options Frame: Rail, Full Depth,

Frame: Rail, Full Depth,

RPO Code List (cont'd) RPO Code List (cont'd)

JRF Shield: Rear Brakes, Dust K60 Generator: 100 AMP

RPO Code List (cont'd) RPO Code List (cont'd)

UEA Taillamp Delete Tire: Front, 245/70R19.5/G, 14PR, BL

RPO Code List (cont'd) RPO Code List (cont'd)

Attachment Main Driveline One-Shaft 003 4.33 Ratio Code

YY7 Paint Process Chassis 010 5.43 Ratio Code