Water-in-Fuel Indicator Sensor Circuit - Voltage Above Normal or Shorted to High S...

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FAULT CODE 428

Water-in-Fuel Indicator Sensor Circuit - Voltage Above
Normal or Shorted to High Source
View Related Topic

Overview

CODE REASON EFFECT

Fault Code: 428 Water-in-Fuel Indicator Sensor Circuit - None on performance.
PID: P097 Voltage Above Normal or Shorted to High No water-in-fuel warning
SPN: 97 Source. High voltage detected at the water- available.
FMI: 3/3 in-fuel circuit.
LAMP: Amber
SRT:

Water-in-Fuel Sensor Circuit

Circuit Description

The water-in-fuel sensor is attached to the fuel filter. The water-in-fuel sensor sends a
signal to the ECM when a set volume of water has accumulated in the fuel filter. The water-
in-fuel circuit contains two wires: A return ground and a SIGNAL wire.

Component Location

The water-in-fuel sensor is integrated into the bottom of the OEM supplied suction fuel filter.
The OEM supplied fuel filter is located on the intake side of the engine. For marine
applications, the water-in-fuel sensor is mounted in a filter housing which contains a
serviceable element. The filter housing location will vary with each OEM.

Shop Talk

The water-in-fuel sensor is integrated into the fuel filter. It is automatically replaced
whenever the fuel filter is replaced. For marine applications, the sensor is not integrated

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into the fuel filter and is a serviceable item. Possible causes for this fault code include:

z Open RETURN or SIGNAL circuit in the harness, connectors, or sensor.

z SIGNAL wire shorted to sensor supply or battery voltage.

Cautions and Warnings

CAUTION
To reduce the possibility of damaging a new ECM, all other active fault
codes must be investigated prior to replacing the ECM.

CAUTION
To reduce the possibility of pin and harness damage, use the following
test lead when taking a measurement:
Part Number 3822758 - male Deutsch/AMP/Metri-Pack test lead.

Troubleshooting Steps

STEPS SPECIFICATIONS
STEP 1. Check the fault codes.
STEP 1A. Check for an active Fault Code 428 active?
fault code.
STEP 2. Check the water-in-fuel sensor
and circuit.
STEP 2A. Inspect the water-in- Dirty or damaged pins?
fuel sensor and connector pins.
STEP 2B. Check the sensor Greater than 100k ohms?
resistance.
STEP 2C. Check the fault codes Fault Code 428 is active?
and verify sensor condition.
STEP 3. Check the ECM and engine
harness.
STEP 3A. Inspect the ECM and Dirty or damaged pins?
engine harness connector pins.
STEP 3B. Check the ECM Fault Code 429 active and Fault Code
response. 428 inactive?
STEP 3C. Check for an open Less than 10 ohms?
circuit in the engine harness.

STEP 3C-1. Check for an open

circuit in the engine harness.

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STEP 3D. Check for a pin to pin Greater than 100k ohms?
short circuit in the engine harness.
STEP 3E. Check for an inactive Fault Code 428 inactive?
fault code.
STEP 4. Clear the fault codes.
STEP 4A. Disable the fault code. Fault Code 428 inactive?
STEP 4B. Clear the inactive fault All fault codes cleared?
codes.

Guided Step 1 - Check the fault codes.

Guided Step 1A - Check for an active fault code.

Conditions

z Turn keyswitch ON.

z Connect INSITE™ electronic
service tool.

Action

Check for an active fault code.

z Use INSITE™ electronic service

tool to read the fault codes.

Fault Code 428 active? Fault Code 428 active?

YES NO
No Repair No Repair
Inactive or Intermittent Fault Code,
Go to 2A
Procedure 019-362.

Guided Step 2 - Check the water-in-fuel sensor and

circuit.

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Guided Step 2A - Inspect the water-in-fuel sensor and connector pins.

Conditions

z Turn keyswitch OFF.

z Disconnect the engine harness
from the water-in-fuel sensor.

Action

Inspect the engine harness, and water-

in-fuel connector pins for the following:

z Loose connector
z Corroded pins
z Bent or broken pins
z Pushed back or expanded pins
z Moisture in or on the connector
z Missing or damaged connector
seals
z Dirt or debris in or on the
connector pins
z Connector shell broken.
z Wire insulation damage
z Damaged locking tab connector.

For general inspection techniques, refer

to Component Connector and Pin
Inspection, Procedure 019-361.

Dirty or damaged pins? Dirty or damaged pins?

YES NO
A damaged connection has been detected No Repair
in the sensor or harness connector.

Clean the connector and pins.

Repair the damaged harness, connector,

or pins, if possible.

Refer to Procedure 019-043.

Go to 4A Go to 2B

Guided Step 2B - Check the sensor resistance.

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Conditions

z Turn
keyswitch
OFF.
z Disconnect
the water-in-
fuel sensor
from the
engine
harness.

Action

Check the sensor

resistance.

z Measure the
resistance
between the
water-in-fuel
SIGNAL pin
and the
water-in-fuel
RETURN pin
at the water-
in-fuel
sensor
connector.

For general
resistance
measurement
techniques, refer
to the Resistance
Measurements
Using a Multimeter
and Wiring
Diagram,
Procedure 019-
360.

Greater than 100k Greater than 100k ohms?

ohms?
YES NO
Replace the water-in- No Repair
fuel sensor.

Refer to Procedure
019-127.

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Go to 4A Go to 2C

Guided Step 2C - Check the fault codes and verify sensor condition.

Conditions

z Turn keyswitch OFF.

z Connect the water-in-fuel sensor to
the engine harness.
z Turn keyswitch ON.
z Connect INSITE™ electronic
service tool.

Action

Check for the appropriate circuit

response after 30 seconds.

z Use INSITE™ electronic service

tool to read the fault codes.

Fault Code 428 is active? Fault Code 428 is active?

YES NO
No Repair None. The removal and installation of the
connector corrected the fault.

Go to 3A Go to 4A

Guided Step 3 - Check the ECM and engine harness.

Guided Step 3A - Inspect the ECM and engine harness connector pins.

Conditions

z Turn keyswitch OFF.

z Disconnect the engine harness
from the ECM.

Action

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Inspect the engine harness and ECM

connector pins for the following:

z Loose connector
z Corroded pins
z Bent or broken pins
z Pushed back or expanded pins
z Moisture in or on the connector
z Missing or damaged connector
seals
z Dirt or debris in or on the
connector pins
z Connector shell broken
z Wire insulation damage
z Damaged locking tab connector.

For general inspection techniques, refer

to Component Connector and Pin
Inspection, Procedure 019-361.

Dirty or damaged pins? Dirty or damaged pins?

YES NO
A damaged connection has been detected No Repair
in the ECM connector or engine harness
connector.

Clean the connector and pins.

Repair the damaged harness, connector,

or pins, if possible.

Refer to Procedure 019-043.

Go to 4A Go to 3B

Guided Step 3B - Check the ECM response.

Conditions

z Turn keyswitch OFF.

z Disconnect the engine harness
from the ECM.
z Place a jumper wire between pin
14 (water-in-fuel sensor SIGNAL
pin) and pin 47 (water-in-fuel
sensor RETURN pin) at the ECM
connector.

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z Turn keyswitch ON.

z Connect INSITE™ electronic
service tool.

Action

Check for the appropriate circuit

response after 30 seconds.

Check for the appropriate circuit

response after 30 seconds.

z Use INSITE™ electronic service

tool to read the fault codes.

Fault Code 429 active and Fault Code Fault Code 429 active and Fault Code
428 inactive? 428 inactive?
YES NO
No Repair Call for pre-authorization.

Replace the ECM.

Refer to Procedure 019-031.

Go to 3C Go to 4A

Guided Step 3C - Check for an open circuit in the engine harness.

Conditions

z Turn
keyswitch
OFF.
z Disconnect
the engine
harness from
the ECM.
z Disconnect
the water-in-
fuel sensor
from the
engine
harness.

Action

Check for an open

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circuit.

z Measure the
resistance
between the
engine
harness
ECM
connector
water-in-fuel
sensor
RETURN pin
and the
engine
harness
water-in-fuel
sensor
connector
RETURN
pin.

Refer to the circuit

diagram or wiring
diagram for
connector pin
identification.

For general
resistance
measurement
techniques, refer
to the Resistance
Measurements
Using a Multimeter
and Wiring
Diagram,
Procedure 019-
360.

Less than 10 Less than 10 ohms?

ohms?
YES NO
No Repair An open RETURN circuit has been detected in the engine
harness.

Repair or replace the engine harness.

Refer to Procedure 019-043.

Go to 3C-1 Go to 4A

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Guided Step 3C-1 - Check for an open circuit in the engine harness.

Conditions

z Turn
keyswitch
OFF.
z Disconnect
the engine
harness from
the ECM.
z Disconnect
the water-in-
fuel sensor
from the
engine
harness.

Action

Check for an open

circuit.

z Measure the
resistance
between the
engine
harness
ECM
connector
water-in-fuel
sensor
SIGNAL pin
and the
engine
water-in-fuel
sensor
connector
SIGNAL pin.

Refer to the circuit

diagram or wiring
diagram for
connector pin
identification.

For general
resistance
measurement
techniques, refer

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to the Resistance
Measurements
Using a Multimeter
and Wiring
Diagram,
Procedure 019-
360.

Less than 10 Less than 10 ohms?

ohms?
YES NO
No Repair An open SIGNAL circuit has been detected in the engine
harness.

Repair or replace the engine harness.

Refer to Procedure 019-043.

Go to 3D Go to 4A

Guided Step 3D - Check for a pin to pin short circuit in the engine harness.

Conditions

z Turn
keyswitch
OFF.
z Disconnect
the engine
harness from
the ECM.
z Disconnect
the water-in-
fuel sensor
from the
engine
harness.

Action

Check for a pin to

pin short.

z Measure the
resistance
between the
water-in-fuel

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SIGNAL pin
in the engine
harness
ECM
connector
and all other
pins in the
engine
harness
connector.

Refer to the circuit

diagram or wiring
diagram for
connector pin
identification.

For general
resistance
measurement
techniques, refer
to the Resistance
Measurements
Using a Multimeter
and Wiring
Diagram,
Procedure 019-
360.

Greater than 100k Greater than 100k ohms?

ohms?
YES NO
No Repair A pin to pin short circuit on the SIGNAL line has been detected in
the engine harness.

Repair or replace the engine harness.

Refer to Procedure 019-043.

Go to 3E Go to 4A

Guided Step 3E - Check for an inactive fault code.

Conditions

z Connect all components.

z Turn keyswitch ON.

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z Connect INSITE™ electronic

service tool.

Action

Check for the appropriate circuit

response after 30 seconds.

z Use INSITE™ electronic service

tool to read the fault codes.

Fault Code 428 inactive? Fault Code 428 inactive?

YES NO
None. The removal and installation of the Troubleshooting procedures need to be
connector corrected the fault. repeated from the beginning. A failure
mode should have been detected.

Go to 4A Go to 1A

Guided Step 4 - Clear the fault codes.

Guided Step 4A - Disable the fault code.

Conditions

z Connect all components.

z Connect INSITE™ electronic
service tool.

Action

Disable the fault code.

z Start the engine and let it idle for 1

minute.
z Use INSITE™ electronic service
tool to verify the fault code is
inactive.

Fault Code 428 inactive? Fault Code 428 inactive?

YES NO
No Repair No Repair

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Go to 4B Go to 1A

Guided Step 4B - Clear the inactive fault codes.

Conditions

z Connect all components.

z Turn keyswitch ON.
z Connect INSITE™ electronic
service tool.

Action

Clear the inactive fault codes.

z Use INSITE™ electronic service

tool to clear the inactive fault
codes.

All fault codes cleared? All fault codes cleared?

YES NO
No Repair No Repair
Repair complete Appropriate troubleshooting steps

Last Modified: 21-Nov-2006

Copyright© 2006
Cummins, Inc.
All rights reserved

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