Electronic Control Modules PDF

LX ELECTRONIC CONTROL MODULES 8E - 1
ELECTRONIC CONTROL MODULES
TABLE OF CONTENTS
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ELECTRONIC CONTROL MODULES - ELECTRONIC CONTROL MODULES - SERVICE

ELECTRICAL DIAGNOSTICS. . . . . . . . . . . . . . . . . 1 INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . 242
ELECTRONIC CONTROL MODULES - ELECTRICAL

DIAGNOSTICS
TABLE OF CONTENTS
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ELECTRONIC CONTROL MODULES - U0159-LOST COMMUNICATION WITH PARK

ELECTRICAL DIAGNOSTICS ASSIST CONTROL MODULE. . . . . . . . . . . . . . . . 54
DIAGNOSIS AND TESTING U0164-LOST COMMUNICATION WITH HVAC
B210D-BATTERY VOLTAGE LOW . . . . . . . . . . . . . . 4 CONTROL MODULE . . . . . . . . . . . . . . . . . . . . . . . 57
B210E-BATTERY VOLTAGE HIGH . . . . . . . . . . . . . 5 U0167-LOST COMMUNICATION WITH
B2112-5 VOLT SUPPLY CIRCUIT LOW . . . . . . . . . 6 INTRUSION TRANSCEIVER CONTROL
B2113-5 VOLT SUPPLY CIRCUIT HIGH . . . . . . . . . 8 MODULE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
B2206-CURRENT VIN MISSING/MISMATCH . . . 10 U0168-LOST COMMUNICATION WITH
B2215-FRONT CONTROL MODULE VEHICLE SECURITY CONTROL MODULE
INTERNAL. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 (SKREEM/WCM) . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
B222C-VEHICLE CONFIGURATION NOT U0169-LOST COMMUNICATION WITH
PROGRAMMED. . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 SUNROOF CONTROL MODULE. . . . . . . . . . . . . 66
U0001-CAN C BUS . . . . . . . . . . . . . . . . . . . . . . . . . . 13 U0181-LOST COMMUNICATION WITH
U0019-CAN B BUS . . . . . . . . . . . . . . . . . . . . . . . . . . 19 HEADLAMP LEVELING TRANSLATOR . . . . . . . 69
U0100-LOST COMMUNICATION WITH U0184-LOST COMMUNICATION WITH
ECM/PCM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 RADIO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
U0101-LOST COMMUNICATION WITH TCM . . . 27 U0186-LOST COMMUNICATION WITH
U0103-LOST COMMUNICATION WITH AUDIO AMPLIFIER . . . . . . . . . . . . . . . . . . . . . . . . . 75
ELECTRIC GEAR SHIFT MODULE . . . . . . . . . . 30 U0193-LOST COMMUNICATION WITH
U0121-LOST COMMUNICATION WITH TRAFFIC INFORMATION RECEIVER
ANTI-LOCK BRAKE MODULE . . . . . . . . . . . . . . . 33 MODULE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78
U0141–LOST COMMUNICATION WITH U0195-LOST COMMUNICATION WITH
FRONT CONTROL MODULE . . . . . . . . . . . . . . . . 36 SDARS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
U0143-LOST COMMUNICATION WITH U0196-LOST COMMUNICATION WITH
MULTI-PURPOSE MODULE (POLICE AND VEHICLE ENTERTAINMENT CONTROL
TAXI INTERFACE MODULE) (PTIM) . . . . . . . . . 39 MODULE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
U0151–LOST COMMUNICATION WITH U0197-LOST COMMUNICATION WITH
OCCUPANT RESTRAINT CONTROLLER HANDS FREE PHONE MODULE . . . . . . . . . . . . 87
(ORC). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 U0199-LOST COMMUNICATION WITH
U0154–LOST COMMUNICATION WITH DRIVER DOOR MODULE . . . . . . . . . . . . . . . . . . . 90
OCCUPANT CLASSIFICATION MODULE . . . . . 45 U0200-LOST COMMUNICATION WITH
U0155-LOST COMMUNICATION WITH PASSENGER DOOR MODULE . . . . . . . . . . . . . . 93
CLUSTER/CCN . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48 U0208-LOST COMMUNICATION WITH
U0156–LOST COMMUNICATION WITH EOM . . 51 HEATED SEAT CONTROL MODULE . . . . . . . . . 96
8E - 2 ELECTRONIC CONTROL MODULES - ELECTRICAL DIAGNOSTICS LX
U0209-LOST COMMUNICATION WITH *NO RESPONSE FROM HSM (HEATED

MEMORY SEAT CONTROL MODULE . . . . . . . . 99 SEAT MODULE) . . . . . . . . . . . . . . . . . . . . . . . . . . 182
U0212-LOST COMMUNICATION WITH *NO RESPONSE FROM HVAC (HEAT
SCCM - CAN B . . . . . . . . . . . . . . . . . . . . . . . . . . . 102 VENTILATION AND A/C) (ATC) . . . . . . . . . . . . . 185
U0231-LOST COMMUNICATION WITH RAIN *NO RESPONSE FROM ITM (INTRUSION
SENSING MODULE . . . . . . . . . . . . . . . . . . . . . . . 105 TRANSCEIVER MODULE) . . . . . . . . . . . . . . . . . 188
U1105-CAN B SIGNAL MISSING . . . . . . . . . . . . . 108 *NO RESPONSE FROM LRSM (LIGHT/RAIN
U1106-CAN C SIGNAL MISSING . . . . . . . . . . . . . 111 SENSOR MODULE) . . . . . . . . . . . . . . . . . . . . . . . 191
U1107-ECU IN SINGLE-WIRE MODE . . . . . . . . . 117 *NO RESPONSE FROM MULTI-PURPOSE
U1108-ADDITIONAL CAN B ECU DETECTED . 122 MODULE (POLICE AND TAXI INTERFACE
U110A-LOST COMMUNICATION WITH MODULE-PTIM). . . . . . . . . . . . . . . . . . . . . . . . . . . 194
SCCM - CAN C . . . . . . . . . . . . . . . . . . . . . . . . . . . 123 *NO RESPONSE FROM MSMD (MEMORY
*STORED LOST COMMUNICATION DTCS . . . 126 SEAT MODULE) . . . . . . . . . . . . . . . . . . . . . . . . . . 197
*CAN C DIAGNOSTIC (+) AND/OR CAN C *NO RESPONSE FROM OCM (OCCUPANT
DIAGNOSTIC (-) CIRCUITS HIGH . . . . . . . . . . 129 CLASSIFICATION MODULE) . . . . . . . . . . . . . . . 200
*CAN C DIAGNOSTIC (+) CIRCUIT LOW . . . . . 131 *NO RESPONSE FROM ORC (OCCUPANT
*CAN C DIAGNOSTIC (-) CIRCUIT LOW . . . . . 133 RESTRAINT CONTROLLER MODULE). . . . . . 204
*CAN C DIAGNOSTIC (+) SHORTED TO *NO RESPONSE FROM PCM
CAN C DIAGNOSTIC (-) . . . . . . . . . . . . . . . . . . . 135 (POWERTRAIN CONTROL MODULE) . . . . . . . 208
*CAN C DIAGNOSTIC (-) CIRCUIT OPEN . . . . 137 *NO RESPONSE FROM PDM (PASSENGER
*CAN C DIAGNOSTIC (+) CIRCUIT OPEN . . . . 139 DOOR MODULE) . . . . . . . . . . . . . . . . . . . . . . . . . 212
*BOTH CAN C DIAGNOSTIC (+) AND CAN C *NO RESPONSE FROM PTS (PARK ASSIST
DIAGNOSTIC (-) CIRCUITS OPEN. . . . . . . . . . 141 MODULE) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 215
*NO RESPONSE FROM ABS (ANTILOCK *NO RESPONSE FROM RADIO . . . . . . . . . . . . . 218
BRAKE MODULE). . . . . . . . . . . . . . . . . . . . . . . . . 144 *NO RESPONSE FROM SDAR (SATELLITE
*NO RESPONSE FROM AMP (AMPLIFIER) . . . 148 RECEIVER) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 221
*NO RESPONSE FROM CCN (CLUSTER) . . . . 151 *NO RESPONSE FROM SCM (STEERING
*NO RESPONSE FROM DDM (DRIVER CONTROL MODULE). . . . . . . . . . . . . . . . . . . . . . 224
DOOR MODULE) . . . . . . . . . . . . . . . . . . . . . . . . . 155 *NO RESPONSE FROM SUNR (SUNROOF
*NO RESPONSE FROM ECM (ENGINE MOTOR/MODULE) . . . . . . . . . . . . . . . . . . . . . . . . 227
CONTROL MODULE) - DIESEL. . . . . . . . . . . . . 158 *NO RESPONSE FROM TCM
*NO RESPONSE FROM EOM (ELECTRONIC (TRANSMISSION CONTROL MODULE) -
OVERHEAD MODULE) . . . . . . . . . . . . . . . . . . . . 161 NAG1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 230
*NO RESPONSE FROM ESM (ELECTRONIC *NO RESPONSE FROM TCM
SHIFT MODULE) (SHIFTER LEVER (TRANSMISSION CONTROL MODULE) –
ASSEMBLY) - NAG1 . . . . . . . . . . . . . . . . . . . . . . 164 NGC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 234
*NO RESPONSE FROM ESM (ELECTRONIC *NO RESPONSE FROM VES (MONITOR/
SHIFT MODULE) - (COLUMN NAG1) . . . . . . . 168 DVD MEDIA SYSTEM). . . . . . . . . . . . . . . . . . . . . 236
*NO RESPONSE FROM FCM (FRONT *NO RESPONSE FROM WCM (WIRELESS
CONTROL MODULE). . . . . . . . . . . . . . . . . . . . . . 172 CONTROL MODULE) – (SENTRY KEY
*NO RESPONSE FROM HFM (HANDS FREE REMOTE ENTRY MODULE) . . . . . . . . . . . . . . . 239
MODULE) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 176
*NO RESPONSE FROM HIDT (HEADLAMP
LEVELING MODULE). . . . . . . . . . . . . . . . . . . . . . 179
LX ELECTRONIC CONTROL MODULES - ELECTRICAL DIAGNOSTICS 8E - 3
ELECTRONIC CONTROL MODULES - ELECTRICAL DIAGNOSTICS

DIAGNOSIS AND TESTING
B210D-BATTERY VOLTAGE LOW

For a complete wiring diagram Refer to Section 8W.
• When Monitored:
With the ignition on.
• Set Condition:
Battery voltage less than 9 volts for approximately 5 to 6 seconds.
Possible Causes
RESISTANCE IN THE BATTERY POSITIVE CIRCUIT

RESISTANCE IN THE GENERATOR CASE GROUND
GENERATOR OPERATION
(K20) GENERATOR FIELD CONTROL CIRCUIT OPEN
(K20) GENERATOR FIELD CONTROL CIRCUIT SHORTED TO GROUND
GROUND CIRCUIT OPEN
PCM
Diagnostic Test
1. CHECK FOR ANY POWERTRAIN CONTROL MODULES DTCS
NOTE: Make sure the Battery is in good condition. Using the Midtronics Battery Tester, test the Battery
before continuing.
NOTE: Inspect the vehicle for after market accessories that may exceed the Generator System output.
NOTE: Make sure the generator drive belt is in good operating condition.
NOTE: Inspect the fuses in the IPM. If an open fuse is found, use the wire diagram/schematic as a guide,
inspect the wiring and connectors for damage.
Turn the ignition on.
With the scan tool, read active PCM DTC’s.
Does the scan tool display any active PCM DTC’s?
Yes >> (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING) for the diagnostic test procedure.
No >> Check the above conditions that can cause a low voltage condition. Repair as necessary.
Perform BODY VERIFICATION TEST – VER 1. (Refer to BODY VERIFICATION TEST – VER 1).
B210E-BATTERY VOLTAGE HIGH

• When Monitored:
• Set Condition:
Battery voltage greater than 16 volts for approximately 5 to 6 seconds.
Possible Causes
(K20) GENERATOR FIELD CONTROL CIRCUIT SHORTED TO BATTERY VOLTAGE

GENERATOR
PCM
Diagnostic Test
1. CHECK FOR ANY POWERTRAIN CONTROL MODULES DTCS

NOTE: Make sure the Battery is in good condition. Using the Midtronics Battery Tester, test the Battery
before continuing.
NOTE: Inspect the vehicle for after market accessories that may exceed the Generator System output.
NOTE: Make sure the generator drive belt is in good operating condition.
NOTE: Inspect the fuses in the IPM. If an open fuse is found, use the wire diagram/schematic as a guide,
inspect the wiring and connectors for damage.
With the scan tool, read active PCM DTC’s.
Does the scan tool display any active PCM DTC’s?
Yes >> (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING) for the diagnostic test procedure.
No >> Check the above conditions that can cause a high voltage condition. Repair as necessary.
B2112-5 VOLT SUPPLY CIRCUIT LOW

• When Monitored:
• Set Condition:
The Front Control Module detects the (F891) 5 volt supply circuit voltage below 4 volts.
Possible Causes
(F891) 5 VOLT SUPPLY CIRCUIT SHORTED TO GROUND

A/C PRESSURE TRANSDUCER
FRONT CONTROL MODULE
Diagnostic Test
1. CHECK FOR ACTIVE DTC

With the scan tool, read the active DTC’s.
Cycle the ignition switch from off to on, leaving the ignition on for a minimum of 90 seconds.
Does the scan tool display this DTC as active?
Yes >> Go To 2
No >> If the DTC is stored, check for an intermittent condition. Visually inspect the related wiring harness con-
nectors. Look for broken, bent, pushed out, or corroded terminals.
2. A/C PRESSURE TRANSDUCER

Turn the ignition off.
Disconnect the A/C Pressure Transducer harness connector.
Yes >> Go To 3
No >> Replace the A/C Pressure Transducer in accordance with the service information.
3. (F891) 5 VOLT SUPPLY CIRCUIT SHORTED TO GROUND

Disconnect the FCM C1 harness connector.
Measure the resistance between ground and the (F891) 5 Volt Supply
circuit.
Is the resistance below 1000.0 ohms?
Yes >> Repair the (F891) 5 Volt Supply circuit for a short to
ground.
Perform BODY VERIFICATION TEST – VER 1. (Refer to
BODY VERIFICATION TEST – VER 1).
No >> Inspect the wiring and connectors for damage or shorted
circuits. If ok, replace and program the Front Control Mod-
ule in accordance with the service information.
B2113-5 VOLT SUPPLY CIRCUIT HIGH

• When Monitored:
• Set Condition:
The Front Control Module detects the (F891) 5 volt supply circuit voltage above 5.0 volts.
Possible Causes
(F891) 5 VOLT SUPPLY CIRCUIT SHORTED TO VOLTAGE

A/C PRESSURE TRANSDUCER
Diagnostic Test

Yes >> Go To 2
2. A/C PRESSURE TRANSDUCER

Disconnect the A/C Pressure Transducer harness connector.
Yes >> Go To 3
No >> Replace the A/C Pressure Transducer in accordance with the service information.
3. (F891) 5 VOLT SUPPLY CIRCUIT SHORTED TO VOLTAGE

Measure the voltage of the (F891) 5 Volt Supply circuit.
Is the voltage above 5.5 volts?
Yes >> Repair the (F891) 5 Volt Supply circuit for a short to volt-
age.
B2206-CURRENT VIN MISSING/MISMATCH

• When Monitored:
• Set Condition:
The Front Control Module will receive and monitor the VIN message from the PCM and record the VIN if
different from the last VIN.
Possible Causes
INCORRECT VIN PROGRAMMED IN PCM
Diagnostic Test

Cycle the ignition switch from off to on at least 5 times, leaving the ignition on for a minimum of 90 seconds per
cycle.
Yes >> Go To 2
2. CHECK VIN IN PCM

With the scan tool compare the VIN that is programmed into the PCM to the VIN on the vehicle.
Does the VIN programmed into the PCM match the vehicles VIN?
Yes >> Inspect the wiring and connectors for damage or shorted circuits. If ok, replace and program the Front
Control Module in accordance with the service information.
No >> Program the correct VIN in the PCM and retest.
B2215-FRONT CONTROL MODULE INTERNAL

• When Monitored:
Continuously.
• Set Condition:
The Front Control Module detects an internal fault.
Possible Causes
Diagnostic Test
1. REPLACE THE FRONT CONTROL MODULE IF DTC IS ACTIVE

With the scan tool, read the active FCM DTC’s.
Yes >> Replace and program the Front Control Module in accordance with the service information.
B222C-VEHICLE CONFIGURATION NOT PROGRAMMED

• When Monitored:
• Set Condition:
The Front Control Module is not configured correctly to the vehicle.
Possible Causes
FRONT CONTROL MODULE NOT CONFIGURED CORRECTLY
Diagnostic Test

cycle.
Yes >> Go To 2
2. CONFIGURE THE FCM TO THE VEHICLE

With the scan tool enter program network configuration and program the FCM to the vehicle configuration.
With the scan tool, erase FCM DTC’s.
cycle.
Yes >> Inspect the wiring and connectors for damage or shorted circuits. If ok, replace and program the Front
No >> Repair is complete.
U0001-CAN C BUS

• When Monitored:
• Set Condition:
The FCM detects a short in either CAN C Bus circuit.
Possible Causes
(D65) CAN C BUS (+) CIRCUIT SHORTED TO GROUND

(D64) CAN C BUS (-) CIRCUIT SHORTED TO GROUND
(D65) CAN C BUS (+) CIRCUIT SHORTED TO VOLTAGE
(D64) CAN C BUS (-) CIRCUIT SHORTED TO VOLTAGE
(D65) CAN C BUS (+) CIRCUIT SHORTED TO (D64) CAN C BUS (-) CIRCUIT
ANTILOCK BRAKE MODULE
POWERTRAIN CONTROL MODULE
SHIFTER LEVER ASSEMBLY (NAG1 ONLY)
ELECTRONIC SHIFT MODULE (COLUMN NAG1)
TRANSMISSION CONTROL MODULE (NAG1 ONLY)
ENGINE CONTROL MODULE (DIESEL)
STEERING CONTROL MODULE
Diagnostic Test
1. TEST FOR INTERMITTENT CONDITION

With the scan tool, record and erase FCM DTC’s.
Cycle the ignition from on to off 3 times.
With the scan tool, read active FCM DTC’s.
Does the scan tool display U0001–CAN C BUS as active?
Yes >> Go To 2
No >> The conditions that caused this code to set are not present at this time. Using the wiring diagram/sche-
matic as a guide, inspect the wiring and connectors.
2. ANTILOCK BRAKE MODULE — INTERNAL SHORT

Disconnect the Antilock Brake Module harness connector.
Yes >> Go To 3
No >> Inspect the wiring and connectors for damage or shorted circuits. If ok, replace the Antilock Brake Mod-
Perform ABS VERIFICATION TEST — VER 1.
3. POWERTRAIN CONTROL MODULE — INTERNAL SHORT

Disconnect the Powertrain Control Module C1 harness connector.
Yes, with Floor Shift
Go To 4
Yes, with Column Shift
Go To 5
No >> Inspect the wiring and connectors for damage or shorted circuits. If ok, replace and program the Pow-
ertrain Control Module in accordance with the service information.
Perform (NGC) POWERTRAIN VERIFICATION TEST VER - 5.
4. SHIFTER LEVER ASSEMBLY (NAG1 ONLY)— INTERNAL SHORT

NOTE: If the vehicle is not equipped with a NAG1 controller then skip this step.
Disconnect the Shifter Lever Assembly harness connector.
Yes >> Go To 6
No >> Inspect the wiring and connectors for damage or shorted circuits. If ok, replace and program the Shifter
Lever Assembly in accordance with the service information.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
5. ELECTRONIC SHIFT MODULE (COLUMN NAG1)— INTERNAL SHORT

Disconnect the Electronic Shift Module harness connector.
Yes >> Go To 6
No >> Inspect the wiring and connectors for damage or shorted circuits. If ok, replace and program the Elec-
tronic Shift Module in accordance with the service information.
6. TRANSMISSION CONTROL MODULE (NAG1 ONLY)— INTERNAL SHORT

Disconnect the Transmission Control Module C2 harness connector.
Yes >> Go To 7
No >> Inspect the wiring and connectors for damage or shorted circuits. If ok, replace and program the Trans-
mission Control Module in accordance with the service information.
7. ENGINE CONTROL MODULE (DIESEL)— INTERNAL SHORT

Disconnect the Engine Control Module C2 harness connector.
Yes >> Go To 8
No >> Inspect the wiring and connectors for damage or shorted circuits. If ok, replace and program the Engine
Perform the ECM VERIFICATION TEST.
8. STEERING CONTROL MODULE — INTERNAL SHORT

Remove the Steering Control Module.
Yes >> Go To 9
No >> Inspect the wiring and connectors for damage or shorted circuits. If ok, replace and program the Steer-
ing Control Module in accordance with the service information.
9. (D65) CAN C BUS (+) CIRCUIT SHORTED TO VOLTAGE

Disconnect the Front Control Module C1 harness connector.
Measure the voltage between the (D65) CAN C Bus (+) circuit and
ground.
Is there any voltage present?
Yes >> Repair the (D65) CAN C Bus (+) circuit for a short to volt-
age.
No >> Go To 10
10. (D64) CAN C BUS (-) CIRCUIT SHORTED TO VOLTAGE

Measure the voltage between the (D64) CAN C Bus (-) circuit and
ground.
Yes >> Repair the (D64) CAN C Bus (-) circuit for a short to volt-
age.
No >> Go To 11
11. (D65) CAN C BUS (+) CIRCUIT SHORTED TO GROUND

Measure the resistance between ground and the (D65) CAN C Bus (+)
circuit.
Is any resistance present?
Yes >> Repair the (D65) CAN C Bus (+) circuit for a short to
ground.
No >> Go To 12
12. (D64) CAN C BUS (-) CIRCUIT SHORTED TO GROUND

Measure the resistance between ground and the (D64) CAN C Bus (-)
circuit.
Yes >> Repair the (D64) CAN C Bus (-) circuit for a short to
ground.
No >> Go To 13
13. (D65) CAN C BUS (+) CIRCUIT SHORTED TO (D64) CAN C BUS (-) CIRCUIT
Measure the resistance between the (D65) CAN C Bus (+) circuit and
the (D64) CAN C Bus (-) circuit.
Yes >> Repair the (D65) CAN C Bus (+) circuit for a short to the
(D64) CAN C Bus (-) circuit.
U0019-CAN B BUS

• When Monitored:
• Set Condition:
The FCM detects an open, a short high, a short low or a short together in either of the CAN B Bus circuits.
Possible Causes
(D55) CAN B BUS (+) CIRCUIT OPEN

(D54) CAN B BUS (-) CIRCUIT OPEN
(D55) CAN B BUS (+) CIRCUIT SHORTED TO VOLTAGE
(D54) CAN B BUS (-) CIRCUIT SHORTED TO VOLTAGE
(D55) CAN B BUS (+) CIRCUIT SHORTED TO GROUND
(D54) CAN B BUS (-) CIRCUIT SHORTED TO GROUND
(D55) CAN B BUS (+) CIRCUIT SHORTED TO (D54) CAN B BUS (-) CIRCUIT
ANY CAN B BUS MODULE
Diagnostic Test

Yes >> Go To 2
2. MEASURE VOLTAGE AT FCM

Gain access to the Front Control Module C1 harness connector, but do not disconnect.
Backprobe and measure the voltage on both the (D55) CAN B Bus (+) and the (D54) CAN B (-) circuits.
Does the voltage read approximately 4.65 - 4.98 volts on the (D54) CAN B Bus (-) and 0.39 - 0.46 volts
on the (D55) CAN B (+) circuits?
Yes >> Go To 3
No - Voltage Between 0.3 - 0.7 Volts on Both Circuits
Go To 9
No - Voltage Reads 0 Volts on Either Circuit
Go To 7
No - Voltage Above 10 Volts on Either Circuit
Go To 5
3. (D55) CAN B BUS (+) CIRCUIT OPEN

With the scan tool select ECU View.
Using a fused jumper wire, connect one end to ground and with the
other end backprobe the (D54) CAN B Bus (-) circuit at the FCM C1
harness connector.
NOTE: A red “X” will appear next to modules that can no longer
communicate on the Bus.
Did a red “X” appear next to any modules on the scan tool?
Yes >> Using the Wiring Diagrams to further isolate the open in the
circuit, repair the (D55) CAN B Bus (+) circuit for an open.
Perform the BODY VERIFICATION TEST – VER 1. (Refer
to BODY VERIFICATION TEST – VER 1).
No >> Go To 4
4. (D54) CAN B BUS (-) CIRCUIT OPEN

With the scan tool select ECU View.
Using a fused jumper wire, connect one end to ground and with the
other end backprobe the (D55) CAN B Bus (+) circuit at the FCM C1
harness connector.
NOTE: A red “X” will appear next to modules that can no longer
communicate on the Bus.
Did a red “X” appear next to any modules on the scan tool?
Yes >> Using the Wiring Diagrams to further isolate the open in the
circuit, repair the (D54) CAN B Bus (-) circuit for an open.
No >> Inspect the wiring and connectors for damage. If ok, replace
and program the Front Control Module in accordance with
the service information. Perform the BODY VERIFICATION
TEST – VER 1. (Refer to BODY VERIFICATION TEST –
VER 1).
5. (D55) CAN B BUS (+) CIRCUIT FOR A SHORT TO VOLTAGE

Measure the voltage between the (D55) CAN B Bus (+) circuit and
ground.
Yes >> Disconnect each CAN B Bus module one at a time while
observing the voltage to determine if the short is caused by
an internal short within a module. Replace the module, in
accordance with the service information, that when discon-
nected eliminates the short to voltage. If the short condition
is still present with all CAN B Bus modules disconnected
use the Wiring Diagrams to help isolate and repair the
(D55) CAN B Bus (+) circuit for a short to voltage.
Perform the BODY VERIFICATION TEST – VER 1. (Refer to BODY VERIFICATION TEST – VER 1).
No >> Go To 6
6. (D54) CAN B BUS (-) CIRCUIT FOR A SHORT TO VOLTAGE

Measure the voltage between the (D54) CAN B Bus (-) circuit and
ground.
observing the voltage to determine if the short is caused by
an internal short within a module. Replace the module, in
accordance with the service information, that when discon-
nected eliminates the short to voltage. If the short condition
is still present with all CAN B Bus modules disconnected
use the Wiring Diagrams to help isolate and repair the
(D54) CAN B Bus (-) circuit for a short to voltage.
No >> Inspect the wiring and connectors for damage. If ok,
replace and program the Front Control Module in accor-
dance with the service information. Perform the BODY
VERIFICATION TEST – VER 1. (Refer to BODY VERIFICA-
TION TEST – VER 1).
7. (D55) CAN B BUS (+) CIRCUIT FOR A SHORT TO GROUND

Measure the resistance between ground and the (D55) CAN B Bus (+)
circuit.
Is the resistance above 1000.0 ohms?
Yes >> Go To 8
No >> Disconnect each CAN B Bus module one at a time while
observing the resistance to determine if the short is caused
by an internal short within a module. Replace the module,
in accordance with the service information, that when dis-
connected eliminates the short to ground. If the short con-
dition is still present with all CAN B Bus modules
disconnected use the Wiring Diagrams to help isolate and
repair the (D55) CAN B Bus (+) circuit for a short to
ground.
8. (D54) CAN B BUS (-) CIRCUIT FOR A SHORT TO GROUND

Measure the resistance between ground and the (D54) CAN B Bus (-)
circuit.
Yes >> Inspect the wiring and connectors for damage. If ok,
replace and program the Front Control Module in accor-
dance with the service information. Perform the BODY
VERIFICATION TEST – VER 1. (Refer to BODY VERIFICA-
TION TEST – VER 1).
No >> Disconnect each CAN B Bus module one at a time while observing the resistance to determine if the
short is caused by an internal short within a module. Replace the module, in accordance with the ser-
vice information, that when disconnected eliminates the short to ground. If the short condition is still
present with all CAN B Bus modules disconnected use the Wiring Diagrams to help isolate and repair
the (D54) CAN B Bus (-) circuit for a short to ground.
Perform the BODY VERIFICATION TEST – VER 1. (Refer to BODY VERIFICATION TEST – VER 1).
9. (D55) CAN B BUS (+) CIRCUIT SHORTED TO THE (D54) CAN B BUS (-) CIRCUIT
Measure the resistance between the (D55) CAN B Bus (+) circuit and
(D54) CAN B Bus (-) circuit.
observing the resistance to determine if the short is caused
by an internal short within a module. Replace the module,
in accordance with the service information, that when dis-
connected eliminates the short between the two circuits. If
the short condition is still present with all CAN B Bus mod-
ules disconnected use the Wiring Diagrams to help isolate
and repair the (D55) CAN B Bus (+) circuit for a short to
the (D54) CAN B Bus (-) circuit.
No >> Inspect the wiring and connectors for damage. If ok, replace and program the Front Control Module in
accordance with the service information. Perform the BODY VERIFICATION TEST – VER 1. (Refer to
U0100-LOST COMMUNICATION WITH ECM/PCM

• When Monitored:
• With the ignition on
• Battery voltage between 10 and 16 volts
• IOD fuse installed
• FCM is configured correctly
• Set Condition:
Bus messages not received from the ECM/PCM for approximately 500ms.
Possible Causes
CAN B OR CAN C BUS CIRCUITS OPEN OR SHORTED

DTCS RELATED TO BATTERY VOLTAGE, IGNITION, OR VIN MESSAGES
FCM NOT CONFIGURED CORRECTLY
ECM/PCM
ECM/PCM POWER AND GROUND
MODULE THAT SET THIS DTC
Diagnostic Test
1. VERIFY DTC IS ACTIVE

NOTE: Ensure the IOD fuse is installed and battery voltage is between 10 and 16 volts before proceeding.
With the scan tool, read active DTCs.
Is this DTC active?
Yes >> Go To 2
No >> Refer to the Stored Lost Communication test procedure. Refer to the table of contents in this section.
2. CHECK FOR ANY OF THE FOLLOWING ACTIVE DTCS

With the scan tool, read all active DTCs from all modules.
NOTE: Check for FCM configuration, CAN B or C hardware electrical, VIN Missing/Mismatch, battery or igni-
tion related DTCs.
Does the scan tool display any active DTCs to the conditions listed above?
Yes >> Diagnose and repair the DTC. Refer to the Table of Contents for a complete list of the symptoms.
No >> Go To 3
3. VERIFY THAT THE ECM/PCM IS ACTIVE ON THE BUS

With the scan tool, select ECU View.
Verify that the ECM/PCM is active on the bus.
Is the ECM/PCM active on the bus?
Yes >> Go To 4
No >> Refer to the Table of Contents located in this section for a no response test procedure.
4. CHECK FOR ADDITIONAL COMMUNICATION RELATED DTCS

With the scan tool, select Network View and select Advanced.
Is there more than one module with active DTCs “Logged Against” the ECM/PCM?
Yes >> Replace/update the ECM/PCM in accordance with the service information.
No >> Replace/update the module that set this DTC in accordance with the service information.
U0101-LOST COMMUNICATION WITH TCM

• When Monitored:
• Set Condition:
Bus messages not received from the TCM for approximately 500ms.
Possible Causes

TCM
TCM POWER AND GROUND
Diagnostic Test

Is this DTC active?
Yes >> Go To 2

tion related DTCs.
No >> Go To 3
3. VERIFY THAT THE TCM IS ACTIVE ON THE BUS

Verify that the TCM is active on the bus.
Is the TCM active on the bus?
Yes >> Go To 4

Is there more than one module with active DTCs “Logged Against” the TCM?
Yes >> Replace/update the TCM in accordance with the service information.
U0103-LOST COMMUNICATION WITH ELECTRIC GEAR SHIFT MODULE

• When Monitored:
• Set Condition:
Bus messages not received from the Electric Gear Shift Module (shifter lever assembly) for approximately
500ms.
Possible Causes

SHIFTER LEVER ASSEMBLY (NAG1 ONLY) POWER AND GROUND
ELECTRONIC SHIFT MODULE (COLUMN NAG1) POWER AND GROUND
Diagnostic Test

Is this DTC active?
Yes >> Go To 2

tion related DTCs.
No >> Go To 3
3. VERIFY THAT THE SHIFTER LEVER ASSEMBLY (NAG 1 ONLY) OR IF APPLICABLE THE ELECTRONIC
SHIFT MODULE (COLUMN NAG 1) IS ACTIVE ON THE BUS
Verify that the Shifter Lever Assembly (NAG 1 Only) or if applicable the Electronic Shift Module (Column NAG 1) is
active on the bus.
Is the Shifter Lever Assembly (NAG 1 Only) or if applicable the Electronic Shift Module (Column NAG
1) active on the bus?
Yes >> Go To 4

Is there more than one module with active DTCs “Logged Against” the Shifter Lever Assembly (NAG 1
Only) or if applicable the Electronic Shift Module (Column NAG 1)?
Yes >> Replace/update the Shifter Lever Assembly (NAG 1 Only) or if applicable the Electronic Shift Module
(Column NAG 1) in accordance with the service information.
U0121-LOST COMMUNICATION WITH ANTI-LOCK BRAKE MODULE

• When Monitored:
• Set Condition:
Bus messages not received from the Antilock Brake Module for approximately 500ms.
Possible Causes

ANTILOCK BRAKE MODULE POWER AND GROUND
Diagnostic Test

Is this DTC active?
Yes >> Go To 2

tion related DTCs.
No >> Go To 3
3. VERIFY THAT THE ABS IS ACTIVE ON THE BUS

Verify that the ABS is active on the bus.
Is the ABS active on the bus?
Yes >> Go To 4

Is there more than one module with active DTCs “Logged Against” the ABS?
Yes >> Replace/update the Antilock Brake Module in accordance with the service information.
No >> Replace/update the module that set this DTC in accordance with the service information
U0141–LOST COMMUNICATION WITH FRONT CONTROL MODULE

• When Monitored:
• Set Condition:
Bus messages not received from the Front Control Module for approximately 2 to 5 seconds.
Possible Causes
CAN B BUS CIRCUITS OPEN OR SHORTED

FRONT CONTROL MODULES POWER AND GROUND
Diagnostic Test

Is this DTC active?
Yes >> Go To 2

tion related DTCs.
No >> Go To 3
3. VERIFY THAT THE FCM IS ACTIVE ON THE BUS

Verify that the FCM is active on the bus.
Is the FCM active on the bus?
Yes >> Go To 4

Is there more than one module with active DTCs “Logged Against” the FCM?
Yes >> Replace/update the Front Control Module in accordance with the service information.
U0143-LOST COMMUNICATION WITH MULTI-PURPOSE MODULE (POLICE AND

TAXI INTERFACE MODULE) (PTIM)

• When Monitored:
• Set Condition:
Bus messages not received from the MPM (PTIM) for approximately 2 to 5 seconds.
Possible Causes

MULTI-PURPOSE MODULE (PTIM)
MULTI-PURPOSE MODULE (PTIM) POWER AND GROUND
Diagnostic Test

Is this DTC active?
Yes >> Go To 2

With the scan tool, read active DTCs from all modules.
tion related DTCs.
No >> Go To 3
3. VERIFY THAT THE MPM (PTIM) IS ACTIVE ON THE BUS

Verify that the MPM (PTIM) is active on the bus.
Is the MPM (PTIM) active on the bus?
Yes >> Go To 4

Is there more than one module with active DTCs “Logged Against” the MPM (PTIM)?
Yes >> Replace/update the Multi-Purpose Module (PTIM) in accordance with the service information.
U0151–LOST COMMUNICATION WITH OCCUPANT RESTRAINT CONTROLLER

(ORC)

• When Monitored:
• Set Condition:
Bus messages not received from the Occupant Restraint Controller for approximately 2 to 5 seconds.
Possible Causes

OCCUPANT RESTRAINT CONTROLLER
OCCUPANT RESTRAINT CONTROLLER POWER AND GROUND
Diagnostic Test

Is this DTC active?
Yes >> Go To 2

tion related DTCs.
No >> Go To 3
3. VERIFY THAT THE ORC IS ACTIVE ON THE BUS

Verify that the ORC is active on the bus.
Is the ORC active on the bus?
Yes >> Go To 4

Is there more than one module with active DTCs “Logged Against” the ORC?
Yes >> Replace/update the Occupant Restraint Controller in accordance with the service information.
Perform AIRBAG VERIFICATION TEST – VER 1.
U0154–LOST COMMUNICATION WITH OCCUPANT CLASSIFICATION MODULE

• When Monitored:
• Set Condition:
Bus messages not received from the Occupant Classification Module for approximately 2 to 5 seconds.
Possible Causes

OCCUPANT CLASSIFICATION MODULE
OCCUPANT CLASSIFICATION MODULE POWER AND GROUND
Diagnostic Test

Is this DTC active?
Yes >> Go To 2

tion related DTCs.
No >> Go To 3
3. VERIFY THAT THE OCM IS ACTIVE ON THE BUS

Verify that the OCM is active on the bus.
Is the OCM active on the bus?
Yes >> Go To 4

Is there more than one module with active DTCs “Logged Against” the OCM?
Yes >> Replace/update the Occupant Classification Module in accordance with the service information.
Perform AIRBAG VERIFICATION TEST – VER 1.
U0155-LOST COMMUNICATION WITH CLUSTER/CCN

• When Monitored:
• Set Condition:
Bus messages not received from the Cluster/CCN for approximately 2 to 5 seconds.
Possible Causes

CLUSTER/CCN
CLUSTER/CCN POWER AND GROUND
MODULE THAT SET THE DTC
Diagnostic Test

Is this DTC active?
Yes >> Go To 2

tion related DTCs.
No >> Go To 3
3. VERIFY THAT THE CCN IS ACTIVE ON THE BUS

Verify that the CCN is active on the bus.
Is the CCN active on the bus?
Yes >> Go To 4

Is there more than one module with active DTCs “Logged Against” the CCN?
Yes >> Replace/update the Cluster (CCN) in accordance with the service information.
U0156–LOST COMMUNICATION WITH EOM

• When Monitored:
• Set Condition:
Bus messages not received from the Electronic Overhead Module (EOM) for approximately 2 to 5 seconds.
Possible Causes

ELECTRONIC OVERHEAD MODULE POWER OR GROUND
ELECTRONIC OVERHEAD MODULE
Diagnostic Test

Is this DTC active?
Yes >> Go To 2

tion related DTCs.
No >> Go To 3
3. VERIFY THAT THE EOM IS ACTIVE ON THE BUS

Verify that the EOM is active on the bus.
Is the EOM active on the bus?
Yes >> Go To 4

Is there more than one module with active DTCs “Logged Against” the EOM?
Yes >> Replace/update the Electronic Overhead Module (EOM) in accordance with the service information.
U0159-LOST COMMUNICATION WITH PARK ASSIST CONTROL MODULE

• When Monitored:
• Set Condition:
Bus messages not received from the Park Assist Module (PTS) for approximately 2 to 5 seconds.
Possible Causes

PARK ASSIST MODULE
PARK ASSIST MODULE POWER OR GROUND
Diagnostic Test

Is this DTC active?
Yes >> Go To 2

tion related DTCs.
No >> Go To 3
3. VERIFY THAT THE PTS IS ACTIVE ON THE BUS

Verify that the PTS is active on the bus.
Is the PTS active on the bus?
Yes >> Go To 4

Is there more than one module with active DTCs “Logged Against” the PTS?
Yes >> Replace/update the Park Assist Module (PTS) in accordance with the service information.
U0164-LOST COMMUNICATION WITH HVAC CONTROL MODULE

• When Monitored:
• Set Condition:
Bus messages not received from the A/C Heater Control (HVAC) for approximately 2 to 5 seconds.
Possible Causes

A/C HEATER CONTROL
A/C HEATER CONTROL POWER AND GROUND
Diagnostic Test

Is this DTC active?
Yes >> Go To 2

tion related DTCs.
No >> Go To 3
3. VERIFY THAT THE HVAC IS ACTIVE ON THE BUS

Verify that the HVAC is active on the bus.
Is the HVAC active on the bus?
Yes >> Go To 4

Is there more than one module with active DTCs “Logged Against” the HVAC?
Yes >> Replace/update the A/C Heater Control in accordance with the service information.
No >> Replace/update the module that set the DTC in accordance with the service information
U0167-LOST COMMUNICATION WITH INTRUSION TRANSCEIVER CONTROL

MODULE

• When Monitored:
• Set Condition:
Bus messages not received from the Intrusion Transceiver Control Module (ITM) for approximately 2 to 5 sec-
onds.
Possible Causes

INTRUSION TRANSCEIVER CONTROL MODULE POWER AND GROUND
INTRUSION TRANSCEIVER CONTROL MODULE
Diagnostic Test

Is this DTC active?
Yes >> Go To 2

tion related DTCs.
Yes >> Diagnose and repair the DTC. Refer to the Index for a complete list of the symptoms.
No >> Go To 3
3. VERIFY THAT THE ITM IS ACTIVE ON THE BUS

Verify that the ITM is active on the bus.
Is the ITM active on the bus?
Yes >> Go To 4
No >> Refer to the No Response test procedure. Refer to the table of contents in this section.

Is there more than one module with active DTCs “Logged Against” the ITM?
Yes >> Replace/update the Intrusion Transceiver Control Module in accordance with the service information.
Perform BODY VERIFICATION TEST – VER 1. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL
MODULES - STANDARD PROCEDURE).
Perform the appropriate VERIFICATION TEST.
U0168-LOST COMMUNICATION WITH VEHICLE SECURITY CONTROL MODULE

(SKREEM/WCM)

• When Monitored:
• Set Condition:
Bus messages not received from the Sentry Key Remote Entry Module (WCM) for approximately 2 to 5 sec-
onds.
Possible Causes

SENTRY KEY REMOTE ENTRY MODULE
SENTRY KEY REMOTE ENTRY MODULE POWER AND GROUND
Diagnostic Test

Is this DTC active?
Yes >> Go To 2

tion related DTCs.
No >> Go To 3
3. VERIFY THAT THE WCM IS ACTIVE ON THE BUS

Verify that the WCM is active on the bus.
Is the WCM active on the bus?
Yes >> Go To 4

Is there more than one module with active DTCs “Logged Against” the WCM?
Yes >> Replace/update the Sentry Key Remote Entry Module in accordance with the service information.
U0169-LOST COMMUNICATION WITH SUNROOF CONTROL MODULE

• When Monitored:
• Set Condition:
Bus messages not received from the Sunroof Control Module (SUNR) for approximately 2 to 5 seconds.
Possible Causes

SUNROOF CONTROL MODULE
SUNROOF CONTROL MODULE POWER AND GROUND
Diagnostic Test

Is this DTC active?
Yes >> Go To 2

tion related DTCs.
No >> Go To 3
3. VERIFY THAT THE SUNR IS ACTIVE ON THE BUS

Verify that the SUNR is active on the bus.
Is the SUNR active on the bus?
Yes >> Go To 4

Is there more than one module with active DTCs “Logged Against” the SUNR?
Yes >> Replace/update the Sunroof Control Module in accordance with the service information.
U0181-LOST COMMUNICATION WITH HEADLAMP LEVELING TRANSLATOR

• When Monitored:
• Set Condition:
Bus messages not received from the Headlamp Leveling Module for approximately 2 to 5 seconds.
Possible Causes

HEADLAMP LEVELING MODULE
HEADLAMP LEVELING MODULE POWER AND GROUND
Diagnostic Test

Is this DTC active?
Yes >> Go To 2

tion related DTCs.
No >> Go To 3
3. VERIFY THAT THE HIDT IS ACTIVE ON THE BUS

Verify that the HIDT is active on the bus.
Is the HIDT active on the bus?
Yes >> Go To 4

Is there more than one module with active DTCs “Logged Against” the HIDT?
Yes >> Replace/update the Headlamp Leveling Module in accordance with the service information.
U0184-LOST COMMUNICATION WITH RADIO

• When Monitored:
• Set Condition:
Bus messages not received from the Radio for approximately 2 to 5 seconds.
Possible Causes

RADIO
RADIO POWER AND GROUND
Diagnostic Test

Is this DTC active?
Yes >> Go To 2

tion related DTCs.
No >> Go To 3
3. VERIFY THAT THE RADIO IS ACTIVE ON THE BUS

Verify that the Radio is active on the bus.
Is the Radio active on the bus?
Yes >> Go To 4

Is there more than one module with active DTCs “Logged Against” the Radio?
Yes >> Replace/update the Radio in accordance with the service information.
U0186-LOST COMMUNICATION WITH AUDIO AMPLIFIER

• When Monitored:
• Set Condition:
Bus messages not received from the Amplifier for approximately 2 to 5 seconds.
Possible Causes

AMPLIFIER
AMPLIFIER POWER AND GROUND
Diagnostic Test

Is this DTC active?
Yes >> Go To 2

tion related DTCs.
No >> Go To 3
3. VERIFY THAT THE AMPLIFIER IS ACTIVE ON THE BUS

Verify that the Amplifier is active on the bus.
Is the Amplifier active on the bus?
Yes >> Go To 4

Is there more than one module with active DTCs “Logged Against” the Amplifier?
Yes >> Replace/update the Amplifier in accordance with the service information.
U0193-LOST COMMUNICATION WITH TRAFFIC INFORMATION RECEIVER MODULE

• When Monitored:
• Set Condition:
Bus messages not received from the Traffic Information Receiver Module (TIRM) for approximately 2 to 5 sec-
onds.
Possible Causes
CAN B BUS CIRCUITS OPEN

(A300) FUSED B(+) CIRCUIT OPEN OR SHORTED
(Z909) GROUND CIRCUIT OPEN
TRAFFIC INFORMATION RECEIVER MODULE (TIRM)
Diagnostic Test

Is this DTC active?
Yes >> Go To 2

tion related DTCs.
Yes >> Diagnose and repair the DTC. Refer to the Index for a complete list of the symptoms.
No >> Go To 3
3. VERIFY THAT THE TIRM IS ACTIVE ON THE BUS

NOTE: A red X will be next to the module that is not communicating, indicating that the module is not active
on the Bus network. A green check indicates that the module is active on the Bus network.
Verify that the TIRM is active on the bus.
Is the TIRM active on the bus?
Yes >> Replace and program the Front Control Module in accordance with the service information.
No >> Go To 4
4. (A300) FUSED B(+) CIRCUIT OPEN

Disconnect the Traffic Information Receiver Module harness connector.
Using a 12-volt test light connected to ground, check the (A300) Fused
B(+) circuit.
Does the test light illuminate brightly?
Yes >> Go To 5
No >> Repair the (A300) Fused B(+) circuit for an open or short.
5. (Z909) GROUND CIRCUIT OPEN

Using a 12-volt test light connected to 12-volts, check the (Z909)
ground circuit.
Yes >> Go To 6
No >> Repair the (Z909) ground circuit for an open.
6. (D55) AND (D54) CAN B BUS CIRCUITS OPEN

NOTE: One open circuit will not cause this condition.
ground.
ground.
Is there any voltage present on either circuit?
Yes >> Replace the Traffic Information Receiver Module in accor-
dance with the service information.
No >> Repair the (D55) and (D54) CAN B Bus circuits for an open.
Inspect the connector for damage.
U0195-LOST COMMUNICATION WITH SDARS

• When Monitored:
• Set Condition:
Bus messages not received from the Satellite Receiver (SDAR) for approximately 2 to 5 seconds.
Possible Causes

SATELLITE RECEIVER
SATELLITE RECEIVER POWER AND GROUND
Diagnostic Test

Is this DTC active?
Yes >> Go To 2

tion related DTCs.
No >> Go To 3
3. VERIFY THAT THE SATELLITE RECEIVER IS ACTIVE ON THE BUS

Verify that the SDARS is active on the bus.
Is the SDARS active on the bus?
Yes >> Go To 4

Is there more than one module with active DTCs “Logged Against” the SDARS?
Yes >> Replace/update the Satellite Receiver in accordance with the service information.
U0196-LOST COMMUNICATION WITH VEHICLE ENTERTAINMENT CONTROL

MODULE

• When Monitored:
• Set Condition:
Bus messages not received from the vehicle entertainment system (DVD player) for approximately 2 to 5 sec-
onds.
Possible Causes

MONITOR/DVD MEDIA SYSTEM
MONITOR/DVD MEDIA SYSTEM POWER AND GROUND
Diagnostic Test

Is this DTC active?
Yes >> Go To 2

tion related DTCs.
No >> Go To 3
3. VERIFY THAT THE VES IS ACTIVE ON THE BUS

Verify that the VES is active on the bus.
Is the VES active on the bus?
Yes >> Go To 4
No >> Refer to the No Response test procedure. Refer to the table of contents in this section.

Is there more than one module with active DTCs “Logged Against” the VES?
Yes >> Replace/update the Monitor/DVD Media System in accordance with the service information.
U0197-LOST COMMUNICATION WITH HANDS FREE PHONE MODULE

• When Monitored:
• Set Condition:
Bus messages not received from the HFM for approximately 2 to 5 seconds.
Possible Causes

HANDS FREE MODULE
HANDS FREE MODULE POWER AND GROUND
Diagnostic Test

Is this DTC active?
Yes >> Go To 2

tion related DTCs.
No >> Go To 3
3. VERIFY THAT THE HFM IS ACTIVE ON THE BUS

Verify that the HFM is active on the bus.
Is the HFM active on the bus?
Yes >> Go To 4

Is there more than one module with active DTCs “Logged Against” the HFM?
Yes >> Replace/update the Hands Free Module in accordance with the service information.
U0199-LOST COMMUNICATION WITH DRIVER DOOR MODULE

• When Monitored:
• Set Condition:
Bus messages not received from the DDM for approximately 2 to 5 seconds.
Possible Causes

DRIVER DOOR MODULE
DRIVER DOOR MODULE POWER AND GROUND
MODULE THAT SET THE DTC
Diagnostic Test

Is this DTC active?
Yes >> Go To 2

tion related DTCs.
No >> Go To 3
3. VERIFY THAT THE DDM IS ACTIVE ON THE BUS

Verify that the DDM is active on the bus.
Is the DDM active on the bus?
Yes >> Go To 4

Is there more than one module with active DTCs “Logged Against” the DDM?
Yes >> Replace/update the Driver Door Module in accordance with the service information.
U0200-LOST COMMUNICATION WITH PASSENGER DOOR MODULE

• When Monitored:
• Set Condition:
Bus messages not received from the PDM for approximately 2 to 5 seconds.
Possible Causes

PASSENGER DOOR MODULE
PASSENGER DOOR MODULE POWER AND GROUND
Diagnostic Test

Is this DTC active?
Yes >> Go To 2

tion related DTCs.
No >> Go To 3
3. VERIFY THAT THE PDM IS ACTIVE ON THE BUS

Verify that the PDM is active on the bus.
Is the PDM active on the bus?
Yes >> Go To 4

Is there more than one module with active DTCs “Logged Against” the PDM?
Yes >> Replace/update the Passenger Door Module in accordance with the service information.
U0208-LOST COMMUNICATION WITH HEATED SEAT CONTROL MODULE

• When Monitored:
• Set Condition:
Bus messages not received from the HSM for approximately 2 to 5 seconds.
Possible Causes

HEATED SEAT MODULE
HEATED SEAT MODULE POWER AND GROUND
Diagnostic Test

Is this DTC active?
Yes >> Go To 2

tion related DTCs.
No >> Go To 3
3. VERIFY THAT THE HSM IS ACTIVE ON THE BUS

Verify that the HSM is active on the bus.
Is the HSM active on the bus?
Yes >> Go To 4

Is there more than one module with active DTCs “Logged Against” the HSM?
Yes >> Replace/update the Heated Seat Module in accordance with the service information.
U0209-LOST COMMUNICATION WITH MEMORY SEAT CONTROL MODULE

• When Monitored:
• Set Condition:
Bus messages not received from the MSMD for approximately 2 to 5 seconds.
Possible Causes

MEMORY SEAT MODULE
MEMORY SEAT MODULE POWER AND GROUND
Diagnostic Test

Is this DTC active?
Yes >> Go To 2

tion related DTCs.
No >> Go To 3
3. VERIFY THAT THE MSMD IS ACTIVE ON THE BUS

Verify that the MSMD is active on the bus.
Is the MSMD active on the bus?
Yes >> Go To 4

Is there more than one module with active DTCs “Logged Against” the MSMD?
Yes >> Replace/update the Memory Seat Module in accordance with the service information.
U0212-LOST COMMUNICATION WITH SCCM - CAN B

• When Monitored:
• Set Condition:
Bus messages not received from the SCM (CAN B) for approximately 2 to 5 seconds.
Possible Causes

STEERING CONTROL MODULE POWER AND GROUND
Diagnostic Test

Is this DTC active?
Yes >> Go To 2

tion related DTCs.
No >> Go To 3
3. VERIFY THAT THE SCM IS ACTIVE ON THE BUS

Verify that the SCM is active on the bus.
Is the SCM active on the bus?
Yes >> Go To 4

Is there more than one module with active DTCs “Logged Against” the SCM?
Yes >> Replace/update the Steering Control Module in accordance with the service information.
U0231-LOST COMMUNICATION WITH RAIN SENSING MODULE

• When Monitored:
• Set Condition:
Bus messages not received from the rain sensor (LRSM) for approximately 2 to 5 seconds.
Possible Causes

RAIN SENSOR
RAIN SENSOR POWER AND GROUND
Diagnostic Test

Is this DTC active?
Yes >> Go To 2

tion related DTCs.
No >> Go To 3
3. VERIFY THAT THE LRSM IS ACTIVE ON THE BUS

Verify that the LRSM is active on the bus.
Is the LRSM active on the bus?
Yes >> Go To 4

Is there more than one module with active DTCs “Logged Against” the LRSM?
Yes >> Replace/update the Rain Sensor in accordance with the service information.
U1105-CAN B SIGNAL MISSING

• When Monitored:
Continuously
• Set Condition:
When the CAN B Bus messages are not received within 2 seconds.
Possible Causes
OTHER CAN B BUS DTC’s SET IN FRONT CONTROL MODULE

Diagnostic Test
1. CHECK FOR ACTIVE DTCS

cycle.
Yes >> Go To 2
2. CHECK FRONT CONTROL MODULE FOR U0019 DTC

With the scan tool, read Front Control Module active DTC’s
Does the scan tool display U0019 CAN B BUS – ACTIVE?
Yes >> Refer to the table of contents in this section and perform the U0019 diagnostic procedure.
No >> Go To 3

Disconnect the Front Control Module C1 connector.
Measure the voltage of the (D55) CAN B Bus (+) circuit.
Is any voltage present on this circuit?
Yes >> Go To 4
No >> Repair the (D55) CAN B Bus (+) circuit for an open.
4. (D54) CAN B BUS (–) CIRCUIT OPEN

Measure the voltage of the (D54) CAN B Bus (-) circuit.
Is any voltage present on this circuit?
Yes >> Replace the Front Control Module in accordance with the
service information.
No >> Repair the (D54) CAN B Bus (–) circuit for an open.
U1106-CAN C SIGNAL MISSING

• When Monitored:
• Set Condition:
The FCM detects a short in either CAN C Bus circuit.
Possible Causes
(D65) CAN C BUS (+) CIRCUIT SHORTED TO GROUND

(D64) CAN C BUS (-) CIRCUIT SHORTED TO GROUND
(D65) CAN C BUS (+) CIRCUIT SHORTED TO VOLTAGE
(D64) CAN C BUS (-) CIRCUIT SHORTED TO VOLTAGE
(D65) CAN C BUS (+) CIRCUIT SHORTED TO (D64) CAN C BUS (-) CIRCUIT
TRANSMISSION CONTROL MODULE (NAG1 ONLY)
ENGINE CONTROL MODULE (DIESEL)
Diagnostic Test

Does the scan tool display U1106–CAN C SIGNAL MISSING as active?
Yes >> Go To 2
2. ANTILOCK BRAKE MODULE — INTERNAL SHORT

Yes >> Go To 3
No >> Inspect the wiring and connectors for damage or shorted circuits. If ok, replace the Antilock Brake Mod-
Perform ABS VERIFICATION TEST — VER 1.
3. POWERTRAIN CONTROL MODULE — INTERNAL SHORT

Disconnect the Powertrain Control Module C1 harness connector.
Yes >> Go To 4
No >> Inspect the wiring and connectors for damage or shorted circuits. If ok, replace and program the Pow-
ertrain Control Module in accordance with the service information.
Perform (NGC) POWERTRAIN VERIFICATION TEST VER - 5.
4. SHIFTER LEVER ASSEMBLY (NAG1 ONLY) OR ELECTRONIC SHIFT MODULE (COLUMN NAG1)—
INTERNAL SHORT
Disconnect the Shifter Lever Assembly or Electronic Shift Module harness connector.
Yes >> Go To 5
No >> Inspect the wiring and connectors for damage or shorted circuits. If ok, replace and program the Shifter
Lever Assembly in accordance with the service information.
5. TRANSMISSION CONTROL MODULE (NAG1 ONLY)— INTERNAL SHORT

Yes >> Go To 7
No >> Inspect the wiring and connectors for damage or shorted circuits. If ok, replace and program the Trans-
mission Control Module in accordance with the service information.
6. ENGINE CONTROL MODULE (DIESEL)— INTERNAL SHORT

Disconnect the Engine Control Module C2 harness connector.
Yes >> Go To 7
No >> Inspect the wiring and connectors for damage or shorted circuits. If ok, replace and program the Engine
7. STEERING CONTROL MODULE — INTERNAL SHORT

Disconnect the Steering Control Module harness connector.
Yes >> Go To 8
No >> Inspect the wiring and connectors for damage or shorted circuits. If ok, replace and program the Steer-
ing Control Module in accordance with the service information.
8. (D65) CAN C BUS (+) CIRCUIT SHORTED TO VOLTAGE

Measure the voltage between the (D65) CAN C Bus (+) circuit and
ground.
Yes >> Repair the (D65) CAN C Bus (+) circuit for a short to volt-
age.
No >> Go To 9
9. (D64) CAN C BUS (-) CIRCUIT SHORTED TO VOLTAGE

Measure the voltage between the (D64) CAN C Bus (-) circuit and
ground.
Yes >> Repair the (D64) CAN C Bus (-) circuit for a short to volt-
age.
No >> Go To 10
10. (D65) CAN C BUS (+) CIRCUIT SHORTED TO GROUND

Measure the resistance between ground and the (D65) CAN C Bus (+)
circuit.
Yes >> Repair the (D65) CAN C Bus (+) circuit for a short to
ground.
No >> Go To 11
11. (D64) CAN C BUS (-) CIRCUIT SHORTED TO GROUND

Measure the resistance between ground and the (D64) CAN C Bus (-)
circuit.
Yes >> Repair the (D64) CAN C Bus (-) circuit for a short to
ground.
No >> Go To 12
12. (D65) CAN C BUS (+) CIRCUIT SHORTED TO (D64) CAN C BUS (-) CIRCUIT
Measure the resistance between the (D65) CAN C Bus (+) circuit and
the (D64) CAN C Bus (-) circuit.
Yes >> Repair the (D65) CAN C Bus (+) circuit for a short to the
(D64) CAN C Bus (-) circuit.
U1107-ECU IN SINGLE-WIRE MODE

• When Monitored:
• Set Condition:
The FCM detects an open, a short high, a short low or a short together in either of the CAN B Bus circuits.
Possible Causes
(D55) CAN B BUS (+) CIRCUIT SHORTED TO GROUND

(D54) CAN B BUS (-) CIRCUIT SHORTED TO GROUND
(D55) CAN B BUS (+) CIRCUIT SHORTED TO VOLTAGE
(D54) CAN B BUS (-) CIRCUIT SHORTED TO VOLTAGE
(D55) CAN B BUS (+) CIRCUIT SHORTED TO (D54) CAN B BUS (-) CIRCUIT
ANY CAN B BUS MODULE
Diagnostic Test

Yes >> Go To 2
2. ANY CAN B BUS MODULE— INTERNAL FAULT

With the scan tool, monitor the active FCM DTCs.
While monitoring the scan tool, disconnect each CAN B Bus module one at a time.
NOTE: When performing the above step, turn the ignition off (wait one minute) before disconnecting any
module. When the module is disconnected turn the ignition on.
NOTE: This is to determine if the fault is internal within a module.
Check for this DTC to become active after disconnecting each CAN B Bus module the vehicle is equipped with.
NOTE: If the DTC becomes stored when a particular CAN B Bus module is disconnected, that module is
causing the DTC to set.
With all the CAN B Bus modules disconnected did the FCM still set this DTC as active?
Yes >> Go To 3
No >> Replace the module that when disconnected the DTC became stored.
3. (D55) CAN B BUS (+) CIRCUIT FOR A SHORT TO VOLTAGE

NOTE: Ensure each CAN B Bus module is disconnected at this
time.
ground.
Yes >> Repair the (D55) CAN B Bus (+) circuit for a short to volt-
age.
No >> Go To 4
4. (D54) CAN B BUS (-) CIRCUIT FOR A SHORT TO VOLTAGE

time.
ground.
Yes >> Repair the (D54) CAN B Bus (-) circuit for a short to volt-
age.
No >> Go To 5
5. (D55) CAN B BUS (+) CIRCUIT FOR A SHORT TO GROUND

time.
Measure the resistance between ground and the (D55) CAN B Bus (+)
circuit.
Yes >> Go To 6
No >> Repair the (D55) CAN B Bus (+) circuit for a short to
ground.
6. (D54) CAN B BUS (-) CIRCUIT FOR A SHORT TO GROUND

time.
Measure the resistance between ground and the (D54) CAN B Bus (-)
circuit.
Yes >> Go To 7
No >> Repair the (D54) CAN B Bus (-) circuit for a short to
ground.
7. (D55) CAN B BUS (+) CIRCUIT SHORTED TO THE (D54) CAN B BUS (-) CIRCUIT
Measure the resistance between the (D55) CAN B Bus (+) circuit and
time.
Yes >> Repair the (D55) CAN B Bus (+) circuit for a short to the
No >> Go To 8

Measure the resistance of the (D55) CAN B Bus (+) circuit between the
FCM connector and the Cluster connector.
Yes >> Repair the (D55) CAN B Bus (+) circuit for an open or high
resistance.
No >> Go To 9
9. (D54) CAN B BUS (-) CIRCUIT OPEN

Measure the resistance of the (D54) CAN B Bus (-) circuit between the
FCM connector and the Cluster connector.
Yes >> Repair the (D54) CAN B Bus (-) circuit for an open or high
resistance.
No >> Replace and program the Front Control Module in accor-
U1108-ADDITIONAL CAN B ECU DETECTED

• When Monitored:
Continuously.
• Set Condition:
The Front Control Module detects an additional CAN B module and requires a re-configuration.
Possible Causes
ADDITIONAL MODULE ADDED/REMOVED FROM THE CAN B BUS NETWORK
Diagnostic Test
1. RECONFIGURE THE FRONT CONTROL MODULE

With the scan tool, select network view and press the gateway button. This will list the CAN modules on the vehicle.
Read and record the listed modules.
With the scan tool, select FCM, miscellaneous functions then add/remove ECUs.
With the scan tool, add or remove the module that was not configured in the FCM.
With the scan tool, erase DTC’s.
Cycle the ignition from on to off 3 times and read the active FCM DTC’s.
Yes >> Retest system and attempt to reconfigure the FCM.
U110A-LOST COMMUNICATION WITH SCCM - CAN C

• When Monitored:
• Set Condition:
Bus messages not received from the SCM (CAN C) for approximately 200ms.
Possible Causes

STEERING CONTROL MODULE POWER AND GROUND
Diagnostic Test

Is this DTC active?
Yes >> Go To 2

tion related DTCs.
No >> Go To 3
3. VERIFY THAT THE SCM IS ACTIVE ON THE BUS

Verify that the SCM is active on the bus.
Is the SCM active on the bus?
Yes >> Go To 4

Is there more than one module with active DTCs “Logged Against” the SCM?
Yes >> Replace/update the Steering Control Module in accordance with the service information.
*STORED LOST COMMUNICATION DTCS

• When Monitored:
• Set Condition:
Bus messages not received for approximately 2 to 5 seconds.
Possible Causes

POWER OR GROUND FROM THE REPORTING MODULE
PREVIOUS SERVICE PERFORMED WITHIN THE LAST 100 KEY CYCLES (FUSE/RELAYS REMOVED, WIRING
SERVICE, BATTERY DISCONNECT)
LOW BATTERY/JUMP START CONDITION
IOD FUSE WAS REMOVED DURING SHIPPING
CHECK FOR RELATED TSBS
Diagnostic Test
1. VERIFY DTC IS STORED

NOTE: Stored faults may indicate a customer perceived intermittent condition.
With the scan tool, read stored DTCs.
Is this DTC stored?
Yes >> Go To 2
No >> Diagnose the active DTC. Refer to the table of contents for a list of the symptoms.
Perform BODY VERIFICATION TEST – VER 1.
2. CHECK THE ENVIRONMENTAL DATA

With the scan tool, read the loss of communication environmental data.
Does the loss of communication environmental odometer data match up to any of the previous service
procedures listed in the possible causes or are there any stored CAN B or C hardware electrical, bat-
tery, ignition voltage, VIN missing/mismatch, FCM configuration DTCs present with match environmental
data?
Yes >> These DTCs may have been the result of other service procedures performed. Clear DTCs.
Perform BODY VERIFICATION TEST – VER 1.
No >> Go To 3
3. VERIFY INTERMITTENT LOST COMMUNICATION DTC-WIRING CONCERNS

Is there more than one ECU with stored DTCs “Logged Against” the module and one or more lost
communication DTCs stored in the offending module?
Yes >> Verify if the vehicle was recently in for this type of service. Otherwise, visually inspect the related wiring
harness for chafed, pierced, pinched, and partially broken wires and the wiring harness connectors for
broken, bent, pushed out, and corroded terminals. Repair as necessary.
No >> Go To 4
4. VERIFY INTERMITTENT LOST COMMUNICATION DTC-OFFENDING MODULE

Is there more than one ECU with stored DTCs “Logged Against” the module and NO lost communica-
tion DTCs stored in the offending module?
Yes >> Check for TSB related to this offending module.
No >> Go To 5
5. VERIFY INTERMITTENT LOST COMMUNICATION DTC-REPORTING MODULE

Is there ONLY ONE ECU with stored DTCs “Logged Against” the module?
Yes >> Check for TSB related to the module that set this DTC.
No >> Verify if the vehicle was recently in for this type of service. Otherwise, visually inspect the related wiring
harness for chafed, pierced, pinched, and partially broken wires and the wiring harness connectors for
broken, bent, pushed out, and corroded terminals. Repair as necessary.
*CAN C DIAGNOSTIC (+) AND/OR CAN C DIAGNOSTIC (-) CIRCUITS HIGH

• When Monitored:
When the scan tool queries the FCM.
• Set Condition:
The scan tool has detected a shorted high condition on either or both CAN C Diagnostic circuits.
Possible Causes
(D72) CAN C DIAGNOSTIC (+) CIRCUIT SHORTED TO VOLTAGE

(D71) CAN C DIAGNOSTIC (-) CIRCUIT SHORTED TO VOLTAGE
Diagnostic Test
1. CHECK THE STATUS OF THE ERROR MESSAGE

NOTE: Ensure the vehicle being tested is a CAN BUS VEHICLE. If not, false error messages may be dis-
played.
NOTE: Ensure the scan tool is updated to the latest software.
With the scan tool, record the error message.
Disconnect the scan tool from the DLC.
Does the scan tool display this same error message?
Yes >> Go To 2
No >> The conditions that caused this error message to set are not present at this time. Using the wiring dia-
gram/schematic as a guide, inspect the wiring and connectors.
2. CAN C DIAGNOSTIC CIRCUITS SHORTED TO VOLTAGE

Measure the voltage of the CAN C Diagnostic circuits.
Is the voltage above 6.0 volts for either circuit?
Yes >> Repair the CAN C Diagnostic circuits for a short to voltage.
circuits. If ok, replace the Front Control Module in accor-
*CAN C DIAGNOSTIC (+) CIRCUIT LOW

• When Monitored:
• Set Condition:
The scan tool has detected a shorted low condition on the (D72) CAN C Diagnostic (+) circuit.
Possible Causes
(D72) CAN C DIAGNOSTIC (+) CIRCUIT SHORTED TO GROUND
Diagnostic Test

played.
Yes >> Go To 2
2. (D72) CAN C DIAGNOSTIC (+) CIRCUIT SHORTED TO GROUND

Measure the resistance between ground and the (D72) CAN C Diag-
nostic (+) circuit.
Yes >> Repair the (D72) CAN C Diagnostic (+) circuit for a short to
ground.
*CAN C DIAGNOSTIC (-) CIRCUIT LOW

• When Monitored:
• Set Condition:
The scan tool has detected a shorted low condition on the (D71) CAN C Diagnostic (-) circuit.
Possible Causes
(D71) CAN C DIAGNOSTIC (-) CIRCUIT SHORTED TO GROUND
Diagnostic Test

played.
Yes >> Go To 2
2. (D71) CAN C DIAGNOSTIC (-) CIRCUIT SHORTED TO GROUND

Measure the resistance between ground and the (D71) CAN C Diag-
nostic (-) circuit.
Yes >> Repair the (D71) CAN C Diagnostic (-) circuit for a short to
ground.
*CAN C DIAGNOSTIC (+) SHORTED TO CAN C DIAGNOSTIC (-)

• When Monitored:
• Set Condition:
The scan tool has detected a shorted together condition on the CAN C Diagnostic circuits.
Possible Causes
(D72) CAN C DIAGNOSTIC (+) CIRCUIT SHORTED TO (D71) CAN C DIAGNOSTIC (-) CIRCUIT
Diagnostic Test

played.
Yes >> Go To 2
2. (D72) CAN C DIAGNOSTIC (+) CIRCUIT SHORTED TO (D71) CAN C DIAGNOSTIC (-) CIRCUIT
Measure the resistance between the (D72) CAN C Diagnostic (+) circuit
and the (D71) CAN C Diagnostic (-) circuit.
Yes >> Repair the (D72) CAN C Diagnostic (+) circuit for a short to
the (D71) CAN C Diagnostic (-) circuit.
*CAN C DIAGNOSTIC (-) CIRCUIT OPEN

• When Monitored:
• Set Condition:
The scan tool has detected an open condition on the (D71) CAN C Diagnostic (-) circuit.
Possible Causes
(D71) CAN C DIAGNOSTIC (-) CIRCUIT OPEN
Diagnostic Test

played.
Yes >> Go To 2
2. (D71) CAN C DIAGNOSTIC (-) CIRCUIT OPEN

Measure the resistance of the (D71) CAN C Diagnostic (-) circuit
between the FCM connector and the DLC.
Yes >> Inspect the wiring and connectors for damage or shorted
No >> Repair the (D71) CAN C Diagnostic (-) circuit for an open.
*CAN C DIAGNOSTIC (+) CIRCUIT OPEN

• When Monitored:
• Set Condition:
The scan tool has detected an open condition on the (D72) CAN C Diagnostic (+) circuit.
Possible Causes
(D72) CAN C DIAGNOSTIC (+) CIRCUIT OPEN
Diagnostic Test

played.
Yes >> Go To 2
2. (D72) CAN C DIAGNOSTIC (+) CIRCUIT OPEN

Measure the resistance of the (D72) CAN C Diagnostic (+) circuit
No >> Repair the (D72) CAN C Diagnostic (+) circuit for an open.
*BOTH CAN C DIAGNOSTIC (+) AND CAN C DIAGNOSTIC (-) CIRCUITS OPEN

• When Monitored:
• Set Condition:
The scan tool has detected an open condition on both CAN C Diagnostic circuits.
Possible Causes
(D72) CAN C DIAGNOSTIC (+) CIRCUIT OPEN

(D71) CAN C DIAGNOSTIC (-) CIRCUIT OPEN
Diagnostic Test

played.
Yes >> Go To 2
2. (D72) CAN C DIAGNOSTIC (+) CIRCUIT OPEN

NOTE: Check the connectors at both the DLC and the FCM.
Measure the resistance of the (D72) CAN C Diagnostic (+) circuit
Yes >> Go To 3
No >> Repair the (D72) CAN C Diagnostic (+) circuit for an open.
3. (D71) CAN C DIAGNOSTIC (-) CIRCUIT OPEN

Measure the resistance of the (D71) CAN C Diagnostic (-) circuit
No >> Repair the (D71) CAN C Diagnostic (-) circuit for an open.
*NO RESPONSE FROM ABS (ANTILOCK BRAKE MODULE)

Possible Causes
(A107) (A111) FUSED B(+) CIRCUIT OPEN OR SHORTED

(F202) FUSED IGNITION SW OUTPUT CIRCUIT OPEN OR SHORTED
(D65) CAN C BUS (+) CIRCUIT OPEN
(D64) CAN C BUS (-) CIRCUIT OPEN
Diagnostic Test

NOTE: Ensure the IOD fuse is installed and battery voltage is between 10.0 and 16.0 volts.
NOTE: Check the FCM for any active CAN C hardware DTCs, perform DTC before proceeding.
Does the scan tool display a red X next to the module?
Yes >> Go To 2
No >> The no response condition is not present at this time. Using the wiring diagram/schematic as a guide,
inspect the wiring for chafed, pierced, pinched, and partially broken wires and the wiring harness con-
nectors for broken, bent, pushed out, and corroded terminals.
2. (A107) (A111) FUSED B(+) CIRCUIT OPEN OR SHORTED

Using a 12-volt test light connected to ground, check each (A107) and
(A111) Fused B(+) circuit.
Does the test light illuminate brightly for each circuit?
Yes >> Go To 3
No >> Repair the Fused B(+) circuit for an open or short.
Perform ABS VERIFICATION TEST - VER 1.

ground circuit.
Yes >> Go To 4
4. (F202) FUSED IGNITION SWITCH OUTPUT CIRCUIT OPEN OR SHORTED

Using a 12-volt test light connected to ground, check the (F202) Fused
Ignition Switch Output circuit.
Yes >> Go To 5
No >> Repair the (F202) Fused Ignition Switch Output circuit for
an open or short.
5. (D65) CAN C BUS (+) CIRCUIT OPEN

Measure the resistance of the (D65) CAN C Bus (+) circuit between the
FCM connector and the Antilock Brake Module connector.
Is resistance below 5.0 ohms?
Yes >> Go To 6
No >> Repair the (D65) CAN C Bus (+) circuit for an open.
6. (D64) CAN C BUS (-) CIRCUIT OPEN

Measure the resistance of the (D64) CAN C Bus (-) circuit between the
FCM connector and the Antilock Brake Module connector.
Yes >> Replace the Antilock Brake Module in accordance with the
No >> Repair the (D64) CAN C Bus (-) circuit for an open.
*NO RESPONSE FROM AMP (AMPLIFIER)

Possible Causes
(X13) FUSED B (+) CIRCUIT OPEN OR SHORTED

(D55) AND (D54) CAN B BUS CIRCUITS OPEN
AMPLIFIER
Diagnostic Test

Yes >> Go To 2
2. (X13) FUSED B(+) CIRCUIT OPEN OR SHORTED

Disconnect the Radio Amplifier C2 harness connector.
Using a 12-volt test light connected to ground, check each (X13) Fused
B(+) circuit.
Yes >> Go To 3
No >> Repair the (X13) Fused B(+) circuit for an open or short.

Using a 12-volt test light connected to 12-volts, check each (Z910)
ground circuit.
Yes >> Go To 4

ground.
ground.
Yes >> Replace the Radio Amplifier in accordance with the service
information.
No >> Repair the (D55) and (D54) CAN B Bus circuits for an
open. Inspect the connector for damage.
*NO RESPONSE FROM CCN (CLUSTER)

Possible Causes
(A917) (A23) (A110) FUSED B(+) CIRCUITS OPEN OR SHORTED

(Z910) (Z210) GROUND CIRCUITS OPEN
(F202) FUSED IGNITION SWITCH OUTPUT CIRCUIT OPEN OR SHORTED
CLUSTER (CCN)
Diagnostic Test

Yes >> Go To 2
2. (A917) (A23) (A110) FUSED B(+) CIRCUITS OPEN OR SHORTED

Disconnect the Cluster harness connectors.
Using a 12-volt test light connected to ground, check each (A917) (A23)
(A110) Fused B(+) circuit.
Yes >> Go To 3
No >> Repair the (A917) (A23) (A110) Fused B(+) circuit for an
open or short.
3. (Z910) (Z210) GROUND CIRCUITS OPEN

(Z210) ground circuit.
Yes >> Go To 4
No >> Repair the (Z910) (Z210) ground circuit for an open.

Yes >> Go To 5
an open or short.

ground.
ground.
Yes >> Replace the Cluster in accordance with the service informa-
tion.
*NO RESPONSE FROM DDM (DRIVER DOOR MODULE)

Possible Causes
(A913) FUSED B (+) CIRCUIT OPEN OR SHORTED

DRIVER DOOR MODULE
Diagnostic Test

Yes >> Go To 2
2. (A913) FUSED B(+) CIRCUIT OPEN OR SHORTED

Disconnect the Driver Door Module harness connectors.
B(+) circuit.
Yes >> Go To 3

ground circuit.
Yes >> Go To 4

ground.
ground.
Yes >> Replace the Driver Door Module in accordance with the
*NO RESPONSE FROM ECM (ENGINE CONTROL MODULE) - DIESEL

Possible Causes
ENGINE CONTROL MODULE POWER AND GROUND

ENGINE CONTROL MODULE
Diagnostic Test

NOTE: Check the FCM for any active CAN C hardware and any ignition related DTCs, perform DTCs before
proceeding.
Yes >> Go To 2
2. CHECK ECM POWER AND GROUND

Check the ECM power and ground circuits. Refer to 9 - ENGINE ELECTRICAL DIAGNOSTICS - DIESEL for the
diagnostic test procedure.
Were any problems found?
Yes >> Repair as necessary.
No >> Go To 3

Disconnect the ECM C2 harness connector.
FCM connector and the ECM connector.
Yes >> Go To 4

FCM connector and the ECM connector.
Yes >> Replace and program the Engine Control Module in accor-
*NO RESPONSE FROM EOM (ELECTRONIC OVERHEAD MODULE)

Possible Causes

ELECTRONIC OVERHEAD MODULE
Diagnostic Test

Yes >> Go To 2

Disconnect the Electronic Overhead Module harness connector.
B(+) circuit.
Yes >> Go To 3

ground circuit.
Yes >> Go To 4

ground.
ground.
Yes >> Replace the Electronic Overhead Module (EOM) in accor-
*NO RESPONSE FROM ESM (ELECTRONIC SHIFT MODULE) (SHIFTER LEVER

ASSEMBLY) - NAG1
Possible Causes
(Z911) OR (Z912) GROUND CIRCUITS OPEN

(F902) IGNITION UNLOCK-RUN-START CIRCUIT OPEN OR SHORTED
SHIFTER LEVER ASSEMBLY (ELECTRONIC SHIFT MODULE)
Diagnostic Test

proceeding.
Yes >> Go To 2
2. CHECK THE (Z911) OR (Z912) GROUND CIRCUIT FOR AN OPEN

Disconnect the Shifter Lever Assembly harness connector.
Using a 12-volt test light connected to 12-volts, check the (Z911) or
Yes >> Go To 3
No >> Repair the (Z911) or (Z912) ground circuit for an open.
Perform NAG1 TRANSMISSION VERIFICATION TEST -
VER 1.
3. (F902) IGNITION UNLOCK–RUN–START CIRCUIT OPEN OR SHORTED

Using a 12-volt test light connected to ground, check the (F902) Ignition
Unlock–Run–Start circuit.
Yes >> Go To 4
No >> Repair the (F902) Ignition Unlock–Run–Start circuit for an
open or short.
VER 1.

FCM connector and the Shifter Lever Assembly connector.
Yes >> Go To 5
VER 1.

FCM connector and the Shifter Lever Assembly connector.
Yes >> Replace the Shifter Lever Assembly in accordance with the
VER 1.
VER 1.
*NO RESPONSE FROM ESM (ELECTRONIC SHIFT MODULE) - (COLUMN NAG1)

Possible Causes
(Z910) GROUND CIRCUITS OPEN

(F902) IGNITION UNLOCK-RUN-START CIRCUIT OPEN OR SHORTED
ELECTRONIC SHIFT MODULE
Diagnostic Test

proceeding.
Yes >> Go To 2
2. CHECK THE (Z910) GROUND CIRCUIT FOR AN OPEN

Disconnect the Electronic Shift Module harness connector.
ground circuit.
Yes >> Go To 3
VER 1.
3. (F902) IGNITION UNLOCK–RUN–START CIRCUIT OPEN OR SHORTED

Using a 12-volt test light connected to ground, check the (F902) Ignition
Unlock–Run–Start circuit.
Yes >> Go To 4
No >> Repair the (F902) Ignition Unlock–Run–Start circuit for an
open or short.
VER 1.

FCM connector and the Electronic Shift Module connector.
Yes >> Go To 5
VER 1.

FCM connector and the Electronic Shift Module connector.
Yes >> Replace the Electronic Shift Module in accordance with the
VER 1.
VER 1.
*NO RESPONSE FROM FCM (FRONT CONTROL MODULE)

Possible Causes
(A106) FUSED B (+) CIRCUIT OPEN AT DLC

(Z910) GROUND CIRCUIT OPEN AT DLC
GROUND CIRCUITS OPEN AT FCM
FUSED B+ CIRCUITS OPEN AT FCM
Diagnostic Test

NOTE: If the scan tool displays any error messages involving the CAN C Diagnostic circuits, diagnose and
repair the error message before proceeding. Refer to the Table of Contents.
NOTE: A loss of communication with the FCM can cause the ECU View button on the scan tool to be inop-
erative (not highlighted).
With the scan tool, attempt to select ECU View.
Can the scan tool communicate with the FCM?
Yes >> The no response condition is not present at this time. Using the wiring diagram/schematic as a guide,
No >> Go To 2
2. (A106) FUSED B(+) CIRCUIT OPEN AT DLC

B(+) circuit.
Yes >> Go To 3
3. (Z910) GROUND CIRCUIT OPEN AT DLC

ground circuit.
Yes >> Go To 4
4. GROUND CIRCUITS OPEN AT FCM C1 CONNECTOR

Using a 12-volt test light connected to 12-volts, check each ground cir-
cuit.
Yes >> Go To 5
No >> Repair the ground circuit for an open. Inspect the connector
for damage.
5. GROUND CIRCUITS OPEN AT FCM PDM CONNECTOR

Remove the FCM from the PDM.
Using a 12-volt test light connected to 12-volts, check each ground cir-
cuit.
Yes >> Go To 6
No >> Repair the ground circuit for an open. Inspect the connector
for damage.
6. FUSED B(+) CIRCUITS OPEN AT FCM PDM CONNECTOR

Using a 12-volt test light connected to ground, check each Fused B(+)
circuit.
Yes >> Replace and program the Front Control Module in accor-
No >> Repair the Fused B(+) circuit for an open. Inspect the con-
nector for damage.
*NO RESPONSE FROM HFM (HANDS FREE MODULE)

Possible Causes

HANDS FREE MODULE
Diagnostic Test

Yes >> Go To 2

Disconnect the Hands Free Module harness connector.
B(+) circuit.
Yes >> Go To 3

ground circuit.
Yes >> Go To 4

ground.
ground.
Yes >> Replace the Hands Free Module in accordance with the
*NO RESPONSE FROM HIDT (HEADLAMP LEVELING MODULE)

Possible Causes
(F500) FUSED RUN RELAY OUTPUT CIRCUIT OPEN OR SHORTED

HEADLAMP LEVELING MODULE
Diagnostic Test

Yes >> Go To 2
2. (F500) FUSED RUN RELAY OUTPUT CIRCUIT OPEN OR SHORTED

NOTE: Check the FCM for any ignition related DTCs before pro-
ceeding. If set (Refer to 8 - ELECTRICAL/IGNITION CONTROL -
DIAGNOSIS AND TESTING).
Disconnect the Headlamp Leveling Module harness connector.
Run Relay Output circuit.
Yes >> Go To 3
No >> Repair the (F500) Fused Run Relay Output circuit for an
open or short.

ground circuit.
Yes >> Go To 4

ground.
ground.
Yes >> Replace the Headlamp Leveling Module in accordance with
the service information.
*NO RESPONSE FROM HSM (HEATED SEAT MODULE)

Possible Causes

HEATED SEAT MODULE
Diagnostic Test

Yes >> Go To 2

Disconnect the Heated Seat Module harness connector.
B(+) circuit.
Yes >> Go To 3

ground circuit.
Yes >> Go To 4

ground.
ground.
Yes >> Replace the Heated Seat Module in accordance with the
*NO RESPONSE FROM HVAC (HEAT VENTILATION AND A/C) (ATC)

Possible Causes

HEAT VENTILATION AND A/C CONTROL (A/C HEATER CONTROL)
Diagnostic Test

Yes >> Go To 2

Disconnect the A/C Heater Control C1 harness connector.
B(+) circuit.
Yes >> Go To 3

ground circuit.
Yes >> Go To 4

ground.
ground.
Yes >> Replace the A/C Heater Control in accordance with the ser-
vice information.
*NO RESPONSE FROM ITM (INTRUSION TRANSCEIVER MODULE)

Possible Causes

INTRUSION TRANSCEIVER MODULE
Diagnostic Test

Yes >> Go To 2

Disconnect the Intrusion Transceiver Module harness connector.
B(+) circuit.
Yes >> Go To 3

ground circuit.
Yes >> Go To 4

ground.
ground.
Yes >> Replace the Intrusion Transceiver Module in accordance
with the service information.
*NO RESPONSE FROM LRSM (LIGHT/RAIN SENSOR MODULE)

Possible Causes
(F880) FUSED ACCESSORY DELAY RELAY OUTPUT CIRCUIT OPEN OR SHORTED

LIGHT/RAIN SENSOR MODULE
Diagnostic Test

Yes >> Go To 2
2. (F880) FUSED ACCESSORY DELAY RELAY OUTPUT CIRCUIT OPEN OR SHORTED

Disconnect the Light/Rain Sensor harness connector.
Accessory Delay Relay Output circuit.
Yes >> Go To 3
No >> Repair the (F880) Fused Accessory Delay Relay Output cir-
cuit for an open or short.

ground circuit.
Yes >> Go To 4

ground.
ground.
Yes >> Replace the Light/Rain Sensor in accordance with the ser-
vice information.
*NO RESPONSE FROM MULTI-PURPOSE MODULE (POLICE AND TAXI INTERFACE

MODULE-PTIM)
Possible Causes

MULTI-PURPOSE MODULE (POLICE AND TAXI INTERFACE MODULE-PTIM)
Diagnostic Test

Yes >> Go To 2

Disconnect the C1 Multi-Purpose Module (Police And Taxi Interface
Module-PTIM) harness connector.
B(+) circuit.
Yes >> Go To 3

ground circuit.
Yes >> Go To 4

ground.
ground.
Yes >> Replace the Multi-Purpose Module (Police And Taxi Inter-
face Module-PTIM) in accordance with the service informa-
tion.
*NO RESPONSE FROM MSMD (MEMORY SEAT MODULE)

Possible Causes

MEMORY SEAT MODULE
Diagnostic Test

Yes >> Go To 2

Disconnect the Memory Seat Module C1 harness connector.
B(+) circuit.
Yes >> Go To 3

ground circuit.
Yes >> Go To 4

ground.
ground.
Yes >> Replace the Memory Seat Module in accordance with the
*NO RESPONSE FROM OCM (OCCUPANT CLASSIFICATION MODULE)

Possible Causes

(R263) SEAT POSITION SENSOR VOLTAGE CIRCUIT FOR A SHORT TO GROUND
(R701) SEAT WEIGHT SENSOR 5 VOLTS CIRCUIT FOR A SHORT TO GROUND
OCCUPANT CLASSIFICATION MODULE
Diagnostic Test

Yes >> Go To 2

WARNING: To avoid personal injury or death, turn the ignition off,
disconnect the battery and wait two minutes before proceeding.
Disconnect the Occupant Classification Module C1 harness connector.
WARNING: To avoid personal injury or death, turn the ignition on,
then reconnect the battery.
B(+) circuit.
Yes >> Go To 3
Perform the OCS VERIFICATION TEST-VER 1.

ground circuit.
Yes >> Go To 4

Yes >> Go To 5
an open or short.

WARNING: If the Occupant Classification Module is dropped at
any time, it must be replaced. Failure to take the proper precau-
tions could result in accidental airbag deployment and personal
injury or death.
ground.
ground.
Yes >> Go To 6
6. CHECK (R263) SEAT POSITION SENSOR VOLTAGE CIRCUIT FOR A SHORT TO GROUND
Measure the resistance between ground and the (R263) Seat Position Sensor Voltage circuit.
Is the resistance below 10k ohms?
Yes >>
NOTE: Do not attempt to repair the Seat Harness. Replace the Seat Harness if the condition inspecting or
testing for is present in the Seat Harness.
Replace the OCM and Driver Seat Position Sensor Harness in accordance with the service information.
No >> Go To 7
7. CHECK (R701) SEAT WEIGHT SENSOR 5 VOLTS CIRCUIT FOR A SHORT TO GROUND
Disconnect the Occupant Classification Module C2 harness connector.
Measure the resistance between ground and the (R701) Seat Weight Sensor 5 volt circuit.
Is the resistance below 10k ohms?
Yes >>
NOTE: Do not attempt to repair the Seat Harness. Replace the Seat Harness if the condition inspecting or
testing for is present in the Seat Harness.
Replace the OCM and Driver Seat Position Sensor Harness in accordance with the service information.
No >> Replace the Occupant Classification Module in accordance with the service information.
*NO RESPONSE FROM ORC (OCCUPANT RESTRAINT CONTROLLER MODULE)

Possible Causes

(F201) FUSED IGNITION SWITCH OUTPUT (RUN/START) CIRCUIT OPEN OR SHORTED
OCCUPANT RESTRAINT CONTROLLER MODULE
Diagnostic Test

Yes >> Go To 2

WARNING: To avoid personal injury or death, turn the ignition off,
disconnect the battery and wait two minutes before proceeding.
Disconnect the Occupant Restraint Controller Module harness connec-
tors.
Connect the appropriate Load Tool ACM Adaptor to the ORC connector.
ground circuit.
Yes >> Go To 3
Perform AIRBAG VERIFICATION TEST - VER 1.

WARNING: To avoid personal injury or death, turn the ignition on,
then reconnect the battery.
Yes >> Go To 4
open or short.
4. (F201) FUSED IGNITION SWITCH OUTPUT (RUN/START) CIRCUIT OPEN OR SHORTED

Ignition Switch Output (RUN/START) circuit.
Yes >> Go To 5
No >> Repair the (F201) Fused Ignition Switch Output (RUN/
START) circuit for an open or short.

WARNING: If the Occupant Restraint Controller is dropped at any
time, it must be replaced. Failure to take the proper precautions
could result in accidental airbag deployment and personal injury
or death.
ground.
Measure the voltage between the (D55) CAN B Bus (+) circuit and ground.
Yes >> Replace the Occupant Restraint Controller Module in accordance with the service information.
No >> Repair the (D55) and (D54) CAN B Bus circuits for an open. Inspect the connector for damage.
*NO RESPONSE FROM PCM (POWERTRAIN CONTROL MODULE)

Possible Causes

Diagnostic Test

Yes >> Go To 2

Disconnect the PCM C1 harness connector.
CAUTION: Do not probe the PCM harness connectors. Probing the
PCM harness connectors will damage the PCM terminals resulting
in poor terminal to pin connection. Install Miller Special Tool #8815
to perform diagnosis.
B(+) circuit.
Yes >> Go To 3
Perform (NGC) POWERTRAIN VERIFICATION TEST VER
- 5.

ground circuit.
Yes >> Go To 4
- 5.

Yes >> Go To 5
an open or short.
- 5.

FCM connector and the appropriate terminal of the special tool #8815.
Yes >> Go To 6
- 5.

FCM connector and the appropriate terminal of the special tool #8815.
Yes >> Replace and program the Powertrain Control Module in
accordance with the service information.
- 5.
- 5.
*NO RESPONSE FROM PDM (PASSENGER DOOR MODULE)

Possible Causes

PASSENGER DOOR MODULE
Diagnostic Test

Yes >> Go To 2

Disconnect the Passenger Door Module harness connectors.
B(+) circuit.
Yes >> Go To 3

ground circuit.
Yes >> Go To 4

ground.
ground.
Yes >> Replace the Passenger Door Module in accordance with
*NO RESPONSE FROM PTS (PARK ASSIST MODULE)

Possible Causes

PARK ASSIST MODULE
Diagnostic Test

Yes >> Go To 2

Disconnect the Park Assist Module harness connector.
Yes >> Go To 3
open or short.

ground circuit.
Yes >> Go To 4

ground.
ground.
Yes >> Replace the Park Assist Module in accordance with the ser-
vice information.
*NO RESPONSE FROM RADIO

Possible Causes

RADIO
Diagnostic Test

Yes >> Go To 2

Disconnect the Radio C1 harness connector.
Using a 12-volt test light connected to ground, check each (A300)
Fused B(+) circuit.
Yes >> Go To 3

ground circuit.
Yes >> Go To 4

ground.
ground.
Yes >> Replace the Radio in accordance with the service informa-
tion.
*NO RESPONSE FROM SDAR (SATELLITE RECEIVER)

Possible Causes

SATELLITE RECEIVER
Diagnostic Test

Yes >> Go To 2

Disconnect the Satellite Receiver harness connector.
B(+) circuit.
Yes >> Go To 3

ground circuit.
Yes >> Go To 4

ground.
ground.
Yes >> Replace the Satellite Receiver in accordance with the ser-
vice information.
*NO RESPONSE FROM SCM (STEERING CONTROL MODULE)

Possible Causes

Diagnostic Test

Yes >> Go To 2

Disconnect/remove the Steering Control Module harness connector.
B(+) circuit.
Yes >> Go To 3

ground circuit.
Yes >> Go To 4

ground.
ground.
Yes >> Replace the Steering Control Module in accordance with
*NO RESPONSE FROM SUNR (SUNROOF MOTOR/MODULE)

Possible Causes
(X13) FUSED B (+) CIRCUIT OPEN OR SHORTED

SUNROOF MOTOR/MODULE
Diagnostic Test

Yes >> Go To 2
2. (X13) FUSED B(+) CIRCUIT OPEN OR SHORTED

Disconnect the Sunroof Motor/Module harness connector.
Using a 12-volt test light connected to ground, check the (X13) Fused
B(+) circuit.
Yes >> Go To 3
No >> Repair the (X13) Fused B(+) circuit for an open or short.

ground circuit.
Yes >> Go To 4

ground.
ground.
Yes >> Replace the Sunroof Motor/Module in accordance with the
*NO RESPONSE FROM TCM (TRANSMISSION CONTROL MODULE) - NAG1

Possible Causes
(Z910) or (Z912) GROUND CIRCUIT OPEN

(F942) FUSED TRANSMISSION RELAY OUTPUT CIRCUIT OPEN OR SHORT
TRANSMISSION CONTROL MODULE
Diagnostic Test

proceeding.
Yes >> Go To 2
2. CHECK THE (Z910) OR (Z912) GROUND CIRCUIT FOR AN OPEN

Using a 12-volt test light connected to 12-volts, check the (Z910) or
Yes >> Go To 3
No >> Repair the (Z910) or (Z912) ground circuit for an open.
VER 1.
3. (F942) FUSED TRANSMISSION RELAY OUTPUT CIRCUIT OPEN OR SHORTED

Transmission Relay Output circuit.
Yes >> Go To 4
No >> Repair the (F942) Fused Transmission Relay Output circuit
for an open or short.
VER 1.

Disconnect the TCM C2 harness connector.
FCM connector and the TCM connector.
Yes >> Go To 5
VER 1.

FCM connector and the TCM connector.
Yes >> Replace the Transmission Control Module in accordance
with the service information.
VER 1.
VER 1.
*NO RESPONSE FROM TCM (TRANSMISSION CONTROL MODULE) – NGC

Possible Causes

Diagnostic Test

Yes >> Go To 2
2. ATTEMPT TO COMMUNICATE WITH THE PCM

With the scan tool in ECU view, observe the status of the PCM.
Does the scan tool display a red X next to the PCM?
Yes >> Refer to the No Response From PCM test procedure. Refer to the table of contents in this section.
No >> Go To 3

Disconnect the PCM C4 harness connector.
CAUTION: Do not probe the PCM harness connectors. Probing the
PCM harness connectors will damage the PCM terminals resulting
in poor terminal to pin connection. Install Miller Special Tool #8815
to perform diagnosis.
ground circuit.
Yes >> Replace and program the Powertrain Control Module in
accordance with the service information.
Perform the appropriate TRANSMISSION VERIFICATION
TEST.
*NO RESPONSE FROM VES (MONITOR/DVD MEDIA SYSTEM)

Possible Causes

MONITOR/DVD MEDIA SYSTEM
Diagnostic Test

Yes >> Go To 2

Disconnect the Monitor/DVD Media System harness connector.
B(+) circuit.
Yes >> Go To 3

ground circuit.
Yes >> Go To 4

ground.
ground.
Yes >> Replace the Monitor/DVD Media System in accordance with
*NO RESPONSE FROM WCM (WIRELESS CONTROL MODULE) – (SENTRY KEY

REMOTE ENTRY MODULE)
Possible Causes
(A23), OR (A917) (RHD) FUSED B(+) CIRCUIT OPEN OR SHORTED

SENTRY KEY REMOTE ENTRY MODULE
Diagnostic Test

Yes >> Go To 2

Disconnect the Sentry Key Remote Entry Module harness connector.
Using a 12-volt test light connected to ground, check the (A23) or
(A917) (RHD) Fused B(+) circuit.
Yes >> Go To 3
No >> Repair the (A23) or (A917) (RHD) Fused B(+) circuit for an
open or short.
Perform SKREEM VERIFICATION TEST.

ground circuit.
Yes >> Go To 4

Yes >> Go To 5
an open or short.

ground.
ground.
Yes >> Replace the Sentry Key Remote Entry Module in accor-
8E - 242 ELECTRONIC CONTROL MODULES - SERVICE INFORMATION LX
ELECTRONIC CONTROL MODULES - SERVICE

INFORMATION
TABLE OF CONTENTS
page page
ELECTRONIC CONTROL MODULES - SERVICE OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 277

INFORMATION MODULE-POWERTRAIN CONTROL
STANDARD PROCEDURE DESCRIPTION
PCM/SKREEM PROGRAMMING . . . . . . . . . . . . . 243 DESCRIPTION - PCM . . . . . . . . . . . . . . . . . . . . . . 278
MODULE-ANTILOCK BRAKE - MK25 MODES OF OPERATION . . . . . . . . . . . . . . . . . . . 278
DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 245 5 VOLT SUPPLIES . . . . . . . . . . . . . . . . . . . . . . . . . 281
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 245 IGNITION CIRCUIT SENSE . . . . . . . . . . . . . . . . . 281
REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 246 POWER GROUNDS . . . . . . . . . . . . . . . . . . . . . . . . 281
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 248 SENSOR RETURN . . . . . . . . . . . . . . . . . . . . . . . . . 282
MODULE-ANTILOCK BRAKE - MK25E OPERATION
DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 250 OPERATION - PCM . . . . . . . . . . . . . . . . . . . . . . . . 282
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 250 5 VOLT SUPPLIES . . . . . . . . . . . . . . . . . . . . . . . . . 283
REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 251 OPERATION - IGNITION CIRCUIT SENSE . . . . 284
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 254 DIAGNOSIS AND TESTING
COMMUNICATION NGC POWERTRAIN VERIFICATION TEST
DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 258 VER - 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 285
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 258 NGC POWERTRAIN VERIFICATION TEST
MODULE-DOOR VER - 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 286
DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 261 NGC POWERTRAIN VERIFICATION TEST
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 261 VER - 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 287
REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 262 NGC POWERTRAIN VERIFICATION TEST
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 262 VER - 4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 288
MODULE-ENGINE CONTROL NGC POWERTRAIN VERIFICATION TEST
DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 263 VER - 5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 290
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 264 NGC POWERTRAIN VERIFICATION TEST
STANDARD PROCEDURE - ECM/SKIM VER - 6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 291
PROGRAMMING - DIESEL . . . . . . . . . . . . . . . . . 266 STANDARD PROCEDURE
REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 268 TCM QUICK LEARN - 42RLE Only . . . . . . . . . . . 291
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 269 TCM ADAPTATION - NAG1 Only . . . . . . . . . . . . . 292
MODULE-FRONT CONTROL REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 292
DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 270 INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 294
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 270 MODULE-TRANSMISSION CONTROL
DIAGNOSIS AND TESTING DESCRIPTION
BODY VERIFICATION TEST – VER 1 . . . . . . . . 272 TRANSMISSION CONTROL MODULE -
REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 273 42RLE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 296
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 273 TRANSMISSION CONTROL MODULE -
MODULE-SEAT MEMORY NAG1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 296
DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 274 OPERATION
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 274 TRANSMISSION CONTROL MODULE -
DIAGNOSIS AND TESTING 42RLE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 297
MEMORY SEAT MODULE . . . . . . . . . . . . . . . . . . 275 TRANSMISSION CONTROL MODULE -
REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 276 NAG1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 299
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 276 STANDARD PROCEDURE
MODULE-STEERING CONTROL TCM QUICK LEARN - 42RLE Only . . . . . . . . . . . 303
DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 277 TCM ADAPTATION - NAG1 Only . . . . . . . . . . . . . 303
LX ELECTRONIC CONTROL MODULES - SERVICE INFORMATION 8E - 243
ELECTRONIC CONTROL MODULES - SERVICE INFORMATION

STANDARD PROCEDURE
PCM/SKREEM PROGRAMMING
NOTE: Before replacing the Powertrain Control Module (PCM), be certain to check the related component/
circuit integrity for failures not detected due to a double fault in the circuit. Most PCM driver/control circuit
failures are caused by internal component failures (i.e. relays and solenoids) and shorted circuits (i.e. pull-
ups, drivers, and switched circuits). These failures are difficult to detect when a double fault has occurred
and only one Diagnostic Trouble Code (DTC) has been set.
NOTE: After a SKREEM/WCM is replaced, the ignition/transponder keys need to be programmed to the new
SKREEM/WCM. Follow the directions on the diagnostic scan tool. The transponder key for the SKREES/
SKIM and the RKE will both be programmed during this operation. There is no need to program the fob of
the key for RKE functionality once the transponder key is programmed to the new SKREEM/WCM.
NOTE: When a PCM and the SKREEM/WCM are replaced at the same time, perform the following steps in
order:
• Program the new PCM.

• Program the new SKREEM/WCM.
• Program all ignition/transponder keys to the new SKREEM/WCM.
(Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - STANDARD PROCEDURE - PCM/SKREEM
PROGRAMMING).
PROGRAMMING THE PCM/SKREEM

The SKIS Secret Key is an ID code that is unique to each SKREEM/WCM. This code is programmed and stored in
the SKREEM/WCM, the PCM, and each ignition key transponder chip. When the PCM or SKREEM/WCM is
replaced, it is necessary to program the Secret Key into the new module using a diagnostic scan tool. Follow the
programming steps outlined in the diagnostic scan tool for “PCM Replaced” or “WCM Replaced” under “Miscella-
neous Functions” for the “WCM/Wireless Control Module” menu item as appropriate.
NOTE: Be certain to enter the correct country code for the SKREEM/WCM. If the incorrect country code is
programmed into the SKREEM/WCM, it cannot be changed and the SKREEM/WCM must be replaced.
NOTE: If the PCM and the SKREEM/WCM are replaced at the same time, all vehicle ignition keys will need
to be programmed into the new SKREEM/WCM.
NOTE: Programming the PCM or SKREEM/WCM is done using a diagnostic scan tool and a PIN to enter
secure access mode. If three attempts are made to enter secure access mode using an incorrect PIN,
secure access mode will be locked out for one hour. To exit this lockout mode, turn the ignition to the RUN
position for one hour then enter the correct PIN. (Ensure all accessories are turned OFF. Also monitor the
battery state and connect a battery charger if necessary).
PROGRAMMING IGNITION KEYS TO THE SKREEM/WCM

Each ignition key transponder also has a unique ID code that is assigned at the time the key is manufactured.
When a key is programmed into the SKREEM/WCM, the transponder ID code is learned by the module and the
transponder acquires the unique Secret Key ID code from the SKREEM/WCM. To program ignition keys into the
SKREEM/WCM, follow the programming steps outlined in the diagnostic scan tool for “Program Ignition Keys or Key
FOBs” under “Miscellaneous Functions” for the “WCM/Wireless Control Module” menu item.
NOTE: A maximum of eight keys can be learned to each SKREEM/WCM. Once a key is learned to a
SKREEM/WCM, that key has acquired the Secret Key for that SKREEM/WCM and cannot be used on any
other vehicle at the same time.
If ignition key programming is unsuccessful, the scan tool will display one of the following error messages:
• Programming Not Attempted - The scan tool attempts to read the programmed key status and there are no
keys programmed into SKREEM memory.
• Programming Key Failed (Possible Used Key From Wrong Vehicle) - SKREEM/WCM is unable to program
an ignition key transponder due to one of the following:
− The ignition key transponder is faulty.
− The ignition key transponder is or has been already programmed to another vehicle.
• 8 Keys Already Learned, Programming Not Done - The SKREEM/FCM transponder ID memory is full.
• Learned Key In Ignition - The ID for the ignition key transponder currently in the ignition lock cylinder is
already programmed into SKREEM/WCM memory.
MODULE-ANTILOCK BRAKE - MK25

DESCRIPTION
The Antilock Brake Module (ABM) is a microproces-
sor-based device which monitors the Antilock Brake
System (ABS) during normal braking and controls it
when the vehicle is in an ABS stop. The ABM also
monitors the Electronic Stability Program (ESP) if so
equipped.
The ABM (3) is mounted to the HCU (2) as part of the
Integrated Control Unit (ICU). The ABM uses a
47-Way connector on the vehicle wiring harness. The
power source for the ABM is through the ignition
switch in the RUN or ON position. The ABM is on the
CAN-C bus.
OPERATION
The primary functions of the Antilock Brake Module (ABM) are to:
• Monitor the Antilock Brake System (ABS) and Electronic Stability Program (ESP) for proper operation.
• Detect wheel locking or wheel slipping tendencies by monitoring the speed of all four wheels of the vehicle.
• Control fluid modulation to the wheel brakes while the system is in ABS or traction control mode.
• Modulates fluid pressure to the wheel brakes to control vehicle yaw rate in ESP mode.
• Store diagnostic information.
• Provide communication to the scan tool while in diagnostic mode.
• Illuminate the amber TCS/ESP indicator in the instrument cluster.
The ABM constantly monitors the ABS and ESP (if equipped) for proper operation. If the ABM detects a fault, it will
turn on the amber TCS/ESP indicator and disable the ABS or ESP if so equipped. The normal base braking system
will remain operational at that time.
The ABM continuously monitors the speed of each wheel through the signals generated by the wheel speed sensors
to determine if any wheel is beginning to lock. When a wheel locking tendency is detected, the ABM commands the
ABM solenoid coils to actuate. The coils then open and close the valves in the HCU that modulate brake fluid
pressure in some or all of the hydraulic circuits. The ABM continues to control pressure in individual hydraulic cir-
cuits until a locking tendency is no longer present.
REMOVAL
1. Disconnect negative (-) battery cable (2) from bat-
tery post and isolate.
2. Disconnect 47-Way wiring connector (5) at ABM

(6).
3. Unclip brake tubes (1, 2 and 10) from two routing

clips (6) along upper radiator support.
4. Unclip brake tube (3) from routing clip (4) below
Fuse And Relay Center.
5. Lift up on entire assembly (5) from mounting grom-
mets (8) and move inboard allowing access to ABM
attaching screws. Do not force brake tubes.
Move assembly just enough to access mount-
ing screws.
6. Remove three screws (2) attaching ABM (1).
7. Slide ABM (1) off HCU (3).

INSTALLATION
1. Align ABM solenoids and pump/motor wiring con-
nector (4) with HCU valves (2) and connector pas-
sage. Slide ABM (1) onto HCU (3).
2. Install three screws (2) attaching ABM (1) to HCU.

Tighten screws to 2 N·m (17 in. lbs.) torque.
3. Position assembly (5) above mounting grommets

(8) and press mounting bracket into place.
4. Clip brake tube (3) to routing clip (4) below Fuse
And Relay Center.
5. Clip brake tubes (1, 2 and 10) to two routing clips
(6) along upper radiator support.
6. Connect 47-way wiring connector (5) at ABM (6).
7. Connect battery negative cable (2) to battery post.

It is important that this is performed properly. (Refer
to 8 - ELECTRICAL/BATTERY SYSTEM - STAN-
DARD PROCEDURE)
8. Perform Diagnostic Verification Test and clear any
faults. (Refer to 5 - BRAKES - DIAGNOSIS AND
TESTING)
MODULE-ANTILOCK BRAKE - MK25E

DESCRIPTION
The Antilock Brake Module (ABM) is a microproces-
sor-based device which monitors the Antilock Brake
System (ABS) during normal braking and controls it
when the vehicle is in an ABS stop. The ABM also
monitors the Electronic Stability Program (ESP) if so
equipped.
The ABM (1) is mounted to the HCU (2) as part of the
Integrated Control Unit (ICU). The ABM uses a
47-Way connector on the vehicle wiring harness. The
power source for the ABM is through the ignition
switch in the RUN or ON position. The ABM is on the
CAN-C bus.
OPERATION
The primary functions of the Antilock Brake Module (ABM) are to:
• Monitor the Antilock Brake System (ABS) and Electronic Stability Program (ESP) for proper operation.
• Detect wheel locking or wheel slipping tendencies by monitoring the speed of all four wheels of the vehicle.
• Control fluid modulation to the wheel brakes while the system is in ABS or traction control mode.
• Modulates fluid pressure to the wheel brakes to control vehicle yaw rate in ESP mode.
• Store diagnostic information.
• Provide communication to the scan tool while in diagnostic mode.
• Illuminate the amber TCS/ESP indicator in the instrument cluster.
The ABM constantly monitors the ABS and ESP (if equipped) for proper operation. If the ABM detects a fault, it will
turn on the amber TCS/ESP indicator and disable the ABS or ESP if so equipped. The normal base braking system
will remain operational at that time.
The ABM continuously monitors the speed of each wheel through the signals generated by the wheel speed sensors
to determine if any wheel is beginning to lock. When a wheel locking tendency is detected, the ABM commands the
ABM solenoid coils to actuate. The coils then open and close the valves in the HCU that modulate brake fluid
pressure in some or all of the hydraulic circuits. The ABM continues to control pressure in individual hydraulic cir-
cuits until a locking tendency is no longer present.
REMOVAL
1. Disconnect negative (-) battery cable (2) from bat-
tery post and isolate.
NOTE: Use this figure in the following step to

release the ABM harness connector cover. It
shows the location of the release tabs.
2. Disconnect ABM harness connector from antilock

brake module (ABM). To do so:
a. Depress tabs on each side of connector cover,
then
b. Pull outward and upward on lower half of cover
until it locks into position pointing straight out-
ward (2). Connector can then be pulled straight
outward off ABM (1).
3. Unclip all brake tubes from two routing clips (1)

along upper radiator support.
4. Unclip right front brake tube (3) from routing clip on
bracket below Fuse And Relay Center.
5. Unclip rear brake tubes (1, 2) from routing clip (3)

on bracket below Fuse And Relay Center.
6. Lift ICU (1) from mounting grommets (2) and move

inboard allowing access to ABM attaching screws.
Do not force brake tubes. Move assembly just
enough to access mounting screws.
7. Remove four screws (1) attaching ABM (2) to HCU.
8. Slide ABM (1) off HCU (2).

INSTALLATION
1. Clean any debris off the mating surfaces of the HCU and ABM.
CAUTION: When installing new O-rings or solenoid valve stem seals, do not use any type of lubricant.
2. If the seals (1) on the solenoid valve stems (2) are

not new, replace them all. Each of the solenoid
valve stem seals must be new to keep out moisture
and debris; do not reuse solenoid valve stem
seals.
3. Replace the pump/motor connector O-ring (1) if it is

not new. Be sure the O-ring is properly seated in
the mounting groove (2).
4. Align components and install the ABM (1) on the

HCU (2).
5. Install the four screws (1) attaching the ABM (2) to

the HCU. Tighten the mounting screws to 2 N·m
(17 in. lbs.).
6. Position ICU (1) above mounting grommets (2)

located in body side rail and press mounting
bracket into place.
7. Clip rear brake tubes (1, 2) to routing clip (3) on

8. Clip right front brake tube (3) to routing clip on

9. Clip brake tubes to two routing clips (1) along
upper radiator support.
CAUTION: Before installing the ABM harness con-

nector (2) on the ABM (1), be sure the seal is prop-
erly installed in the connector.
10. Insert ABM harness connector (2) into socket of

ABM (1) and close cover, locking connector in
place.
11. Connect battery negative cable (2) to battery post.

It is important that this is performed properly.
(Refer to 8 - ELECTRICAL/BATTERY SYSTEM -
STANDARD PROCEDURE)
12. Perform Diagnostic Verification Test and clear any
faults. (Refer to 5 - BRAKES - DIAGNOSIS AND
TESTING)
COMMUNICATION
DESCRIPTION
The primary on-board communication network between microprocessor-based electronic control modules in this
vehicle is the Controller Area Network (CAN) data bus system. A data bus network minimizes redundant wiring con-
nections; and, at the same time, reduces wire harness complexity, sensor current loads and controller hardware by
allowing each sensing device to be connected to only one module (also referred to as a node). Each node reads,
then broadcasts its sensor data over the bus for use by all other nodes requiring that data. Each node ignores the
messages on the bus that it cannot use.
The CAN bus is a two-wire multiplex system. Multiplexing is any system that enables the transmission of multiple
messages over a single channel or circuit. The CAN bus is used for communication between all vehicle nodes.
However, in addition to the CAN bus network, certain nodes may also be equipped with a dedicated Serial Con-
troller Interface (SCI) or a K-Line serial link bus to provide direct communication between that node and certain
sensor inputs.
There are actually three separate CAN bus systems used in the vehicle. They are designated: the CAN-B, the
CAN-C and the Diagnostic CAN-C. The CAN-B and CAN-C systems provide on-board communication between all
nodes in the vehicle. The CAN-C is the faster of the two systems providing near real-time communication (500
Kbps), but is less fault tolerant than the CAN-B system. The CAN-C is used exclusively for communications
between critical powertrain and chassis nodes. The slower (83.3 Kbps), but more fault tolerant CAN-B system is
used for communications between body and interior nodes. The CAN-B fault tolerance comes from its ability to
revert to a single wire communication mode if there is a fault in the bus wiring.
The added speed of the CAN data bus is many times faster than previous data bus systems. This added speed
facilitates the addition of more electronic control modules or nodes and the incorporation of many new electrical and
electronic features in the vehicle. The Diagnostic CAN-C bus is also capable of 500 Kbps communication, and is
sometimes informally referred to as the CAN-D system to differentiate it from the other high speed CAN-C bus. The
Diagnostic CAN-C is used exclusively for the transmission of diagnostic information between the Front Control Mod-
ule/Central GateWay (FCM or FCMCGW) and a diagnostic scan tool connected to the industry-standard 16-way
Data Link Connector (DLC) located beneath the instrument panel on the driver side of the vehicle.
The FCM is located on the Integrated Power Module (IPM), which is located in the engine compartment near the
battery. The central CAN gateway or hub module integral to the FCM is connected to all three CAN buses. This
gateway physically and electrically isolates the CAN buses from each other and coordinates the bi-directional trans-
fer of messages between them.
OPERATION
The Controller Area Network (CAN) data bus allows all electronic modules or nodes connected to the bus to share
information with each other. Regardless of whether a message originates from a module on the low speed CAN-B
bus or on the high speed CAN-C or CAN-D bus, the message structure and layout is similar, which allows the Front
Control Module/Central GateWay (FCM or FCMCGW) to process and transfer messages between the buses. The
FCM also stores a Diagnostic Trouble Code (DTC) for certain bus network faults.
All modules (also referred to as nodes) transmit and receive messages over one of these buses. Data exchange
between nodes is achieved by serial transmission of encoded data messages. Each node can both send and
receive serial data simultaneously. Bus messages are carried over the data bus in the form of Variable Pulse Width
Modulated (VPWM) signals which, when the high and low voltage pulses are strung together, form a message. Each
node uses arbitration to sort the message priority if two competing messages are attempting to be broadcast at the
same time.
The voltage network used to transmit messages requires biasing and termination. Each module on the bus network
provides its own biasing and termination. Each node terminates the bus through a terminating resistor and a ter-
minating capacitor. There are two types of nodes on the bus. The dominant node terminates the bus through a 1
KW resistor and a 3300 pF capacitor, typically resulting in about a 3300 ohm termination resistance. However, this
resistance value may vary somewhat by application. The FCM (or FCMCGW) is the only dominant node in this
network. A non-dominant (or recessive) node terminates the bus through an 11 KW resistor and a 330 pF capacitor,
typically resulting in about a 10800 ohm termination resistance.
The communication protocol being used for the CAN data bus is a non-proprietary, open standard adopted from the
Bosch CAN Specification 2.0b. The CAN-C is the faster of the two primary buses in the CAN bus system, providing
near real-time communication (500 Kbps).
The CAN bus nodes are connected in parallel to the two-wire bus using a twisted pair, where the wires are wrapped
around each other to provide shielding from unwanted electromagnetic induction, thus preventing interference with
the relatively low voltage signals being carried through them. The twisted pairs have between 33 and 50 twists per
meter. While the CAN bus is operating (active), one of the bus wires will carry a higher voltage and is referred to as
the CAN High or CAN bus (+) wire, while the other bus wire will carry a lower voltage and is referred to as the CAN
Low or CAN bus (–) wire. Refer to the CAN Bus Voltages table.
CAN Bus Voltages (Normal Operation)

Recessive Dominant CAN-L CAN-H CAN-L CAN-H CAN-H
CAN-C Bus
Sleep (Bus (Bus Short to Short to Short to Short to Short to
Circuits
Idle) Active) Ground Ground Battery Battery CAN-L
Battery
2.4 - 2.5 1.3 - 2.3 0.3 - Battery Voltage
CAN-L (–) 0V 0V 2.45 V
V V 0.5V Voltage Less 0.75
V
Battery
2.4 - 2.5 2.6 - 3.5 Voltage Battery
CAN-H (+) 0V 0.02 V 0V 2.45 V
V V Less 0.75 Voltage
V
Key-On CAN-L CAN-H CAN-L CAN-H CAN-H
CAN-B Bus
Key-Off (Bus Asleep) (Bus Short to Short to Short to Short to Short to
Circuits
Active) Ground Ground Battery Battery CAN-L
4.65 - 4.5 - 4.7 Battery 4.5 - 4.7 0.3 - 0.7
CAN-L (–) 10.99 V 0V
4.98 V V Voltage V V
0.39 - 0.3 - 0.7 0.3 - 0.7 Battery 0.3 - 0.7
CAN-H (+) 0.0 V 0V
0.46 V V V Voltage V
Notes
All measurements taken between node ground and CAN terminal with a standard DVOM.
DVOM will display average network voltage.
Total resistance of CAN-C network can also be measured (60 ohms). Cannot measure total resistance of CAN-B
network.
In order to minimize the potential effects of Ignition-Off Draw (IOD), the CAN-B network employs a sleep strategy.
However, a network sleep strategy should not be confused with the sleep strategy of the individual nodes on that
network, as they may differ. For example: The CAN-C bus network is awake only when the ignition switch is in the
ON or START positions; however, the FCM, which is on the CAN-C bus, may still be awake with the ignition switch
in the ACCESSORY or UNLOCK positions. The integrated circuitry of an individual node may be capable of pro-
cessing certain sensor inputs and outputs without the need to utilize network resources.
The CAN-B bus network remains active until all nodes on that network are ready for sleep. This is determined by
the network using tokens in a manner similar to polling. When the last node that is active on the network is ready
for sleep, and it has already received a token indicating that all other nodes on the bus are ready for sleep, it
broadcasts a bus sleep acknowledgment message that causes the network to sleep. Once the CAN-B bus net-
work is asleep, any node on the bus can awaken it by transmitting a message on the network. The FCM will keep
either the CAN-B or the CAN-C bus awake for a timed interval after it receives a diagnostic message for that bus
over the Diagnostic CAN-C bus.
In the CAN system, available options are configured into the FCM at the assembly plant, but additional options can
be added in the field using the diagnostic scan tool. The configuration settings are stored in non-volatile memory.
The FCM also has two 64-bit registers, which track each of the as-built and currently responding nodes on the
CAN-B and CAN-C buses. The FCM stores a Diagnostic Trouble Code (DTC) in one of two caches for any detected
active or stored faults in the order in which they occur. One cache stores powertrain (P-Code), chassis (C-Code)
and body (B-Code) DTCs, while the second cache is dedicated to storing network (U-Code) DTCs.
If there are intermittent or active faults in the CAN network, a diagnostic scan tool connected to the Diagnostic
CAN-C bus through the 16-way Data Link Connector (DLC) may only be able to communicate with the FCM. To aid
in CAN network diagnosis, the FCM will provide CAN-B and CAN-C network status information to the scan tool
using certain diagnostic signals. In addition, the transceiver in each node on the CAN-C bus will identify a bus off
hardware failure, while the transceiver in each node on the CAN-B bus will identify a general bus hardware fail-
ure. The transceivers for some CAN-B nodes will also identify certain failures for both CAN-B bus signal wires.
MODULE-DOOR
DESCRIPTION
The door modules control the express up and down
feature as well as normal window functions. It is used
only on vehicles equipped with the express up feature.
If equipped with memory system, the door module
controls the memory mirror. The modules are attached
to each front door trim panel.
OPERATION
If the vehicle is equipped with the Express Up power window feature there will be a door module on each front door
trim panel. The power window switches and motors are directly wired to the modules. If the vehicle is equipped with
the Memory System, the exterior power mirrors and switches are also directly wired to the modules along with the
rear door window switches. The modules are wired to the accessory delay relay which allows the operation of the
windows and mirrors for a given period of time after the ignition is turned off and providing the doors are not
opened. The modules communicate with each other and other modules on the vehicle via the CAN-B bus circuit.
There are several Diagnostic Trouble Codes (DTC’s) the modules will store if there are problems with the power
window system or the memory power mirror system.
ANTI-PINCH
The 9Anti-Pinch9 function is a safety feature that senses obstacles at the top of the glass and anywhere on the seal
where it meets the glass to close during the window closing operation. When a front window switch is pressed to
the 9Auto-Up9 position and the closing window traps an object and the sense current passes its limit, the module will
stop the motor and drive the window down approximately 200 millimeters. The pinch force is speed dependent
which means that if the vehicle is going over 2km per hour the pinch force will be higher than if the vehicle is
stopped.
PANIC MODE
If the window switch is held in the 9Auto-Up9 position and the closing window traps an object, the module will stop
the motor and when the switch is released will drive the window in the opposite direction approximately 10 millime-
ters. If within 8 seconds after the switch was released to the neutral position, the switch is held again to the 9Auto-
Up9 position, the module will enter the second panic mode. During the second panic mode, the module will drive the
motor with full (stall) force and stop. If within 8 seconds after the switch is released again to the neutral position, the
switch is held again to the 9Auto-Up9 position, the module will drive the motor again with full (stall) force and stop.
REMOVAL
NOTE: A battery reconnect procedure must be per-
formed anytime the battery has been discon-
nected. (Refer to 8 - ELECTRICAL/BATTERY
SYSTEM - STANDARD PROCEDURE).
1. Disconnect and isolate the battery negative cable.

2. Remove front door trim panel (Refer to 23 - BODY/
DOOR - FRONT/TRIM PANEL - REMOVAL).
3. Disconnect electrical harness connectors.
4. Remove mounting fasteners and module.
INSTALLATION
formed anytime the battery has been discon-
nected. (Refer to 8 - ELECTRICAL/BATTERY
SYSTEM - STANDARD PROCEDURE).
1. Position module.
2. Install and tighten mounting fasteners.
3. Connect electrical harness connectors.
4. Install door trim panel (Refer to 23 - BODY/DOOR
- FRONT/TRIM PANEL - INSTALLATION).
5. Connect battery negative cable.
MODULE-ENGINE CONTROL
DESCRIPTION
The ECM is located in the left side of engine compart-
ment attached to the left inner fender behind the bat-
tery.
The electrical circuits at the ECM are split into two
separate wiring harnesses (vehicle and engine wiring
harness). The 58-pin connector is used for the vehicle
wiring harness. The 96-pin connector is for the engine
wiring harness.
The ECM connectors use slide locks. To remove the
ECM connectors, pull the slide locks sideways to the
end of their travel and lift the connectors.
A 32-bit microprocessor uses control algorithms to process the input signals and calculates the injected fuel based
on stored maps. The microprocessor triggers the driver stages for switching the output components. The ECM con-
tains the following data storage elements:
1. Flash EPROM—stores engine-specific curves, engine-management maps, and variant coding (engine and equip-
ment options).
2. EEPROM—stores immobilizer data, calibration and manufacturing data, adaptation values, operational faults and
variant coding.
3. RAM—stores variable data such as calculations data and input values.
OPERATION
The ECM has been programmed to monitor different
circuits of the diesel fuel injection system. This moni-
toring is called on-board diagnostics. Certain criteria
must be met for a diagnostic trouble code to be
entered into the ECM memory. The criteria may be a
range of: engine rpm, engine temperature, time or
other input signals to the ECM. If all of the criteria for
monitoring a system or circuit are met, and a problem
is sensed, then a DTC will be stored in the ECM
memory. It is possible that a DTC for a monitored cir-
cuit may not be entered into the ECM memory, even
though a malfunction has occurred. This may happen
when the monitoring criteria have not been met. The
ECM compares input signal voltages from each input
device with specifications (the established high and
low limits of the input range) that are programmed into
it for that device. If the input voltage is not within the
specifications and other trouble code criteria are met,
a DTC will be stored in the ECM memory.
ECM OPERATING MODES

As input signals to the ECM change, the ECM adjusts its response to the output devices. For example, the ECM
must calculate a different fuel quantity and fuel timing for engine idle condition than it would for a wide open throttle
condition. There are several different modes of operation that determine how the ECM responds to the various input
signals.
Ignition Switch On (Engine Off)
When the ignition is turned on, the ECM activates the glow plug relay for a time period that is determined by engine
coolant temperature, atmospheric temperature and battery voltage.
Engine Start-Up Mode
The ECM uses the engine temperature sensor and the crankshaft position sensor (engine speed) inputs to deter-
mine fuel injection quantity.
Normal Driving Modes
Engine idle, warm-up, acceleration, deceleration and wide open throttle modes are controlled based on all of the
sensor inputs to the ECM. The ECM uses these sensor inputs to adjust fuel quantity and fuel injector timing.
Limp-In Mode
If there is a fault detected with the accelerator pedal position sensor, the ECM will set the engine speed at 1100
RPM.
Overspeed Detection Mode
If the ECM detects engine RPM that exceeds 5200 RPM, the ECM will set a DTC in memory and illuminate the MIL
until the DTC is cleared.
After-Run Mode
The ECM transfers RAM information to ROM and performs an Input/Output state check.
MONITORED CIRCUITS
The ECM is able to monitor and identify most driveability related trouble conditions. Some circuits are directly mon-
itored through ECM feedback circuitry. In addition, the ECM monitors the voltage state of some circuits and com-
pares those states with expected values. Other systems are monitored indirectly when the ECM conducts a
rationality test to identify problems. Although most subsytems of the engine control module are either directly or
indirectly monitored, there may be occasions when diagnostic trouble codes are not immediately identified. For a
trouble code to set, a specific set of conditions must occur and unless these conditions occur, a DTC will not set.
DIAGNOSTIC TROUBLE CODES

Each diagnostic trouble code (DTC) is diagnosed by following a specific procedure. The diagnostic test procedure
contains step-by-step instruction for determining the cause of the DTC as well as no trouble code problems. Refer
to the appropriate Diesel Powertrain Diagnostic Manual for more information.
HARD CODE
A DTC that comes back within one cycle of the ignition key is a hard code. This means that the problem is current
every time the ECM/SKIM checks that circuit or function. Procedures in this manual verify if the DTC is a hard code
at the beginning of each test. When the fault is not a hard code, an intermittent test must be performed. NOTE: If
the DRBIIIT displays faults for multiple components (i.e. ECT, VSS, IAT sensors) identify and check the shared cir-
cuits for possible problems before continuing (i.e. sensor grounds or 5-volt supply circuits). Refer to the appropriate
schematic to identify shared circuits. Refer to the appropriate Diesel Powertrain Diagnostic Manual for more infor-
mation.
INTERMITTENT CODE
A DTC that is not current every time the ECM/SKIM checks the circuit or function is an intermittent code. Most
intermittent DTCs are caused by wiring or connector problems. Problems that come and go like this are the most
difficult to diagnose; they must be looked for under specific conditions that cause them. NOTE: Electromagnetic
(radio) interference can cause an intermittent system malfunction. This interference can interrupt communica-
tion between the ignition key transponder and the SKIM. The following checks may assist you in identifying a pos-
sible intermittent problem:
• Visually inspect the related wire harness connectors. Look for broken, bent, pushed out or corroded terminals.
• Visually inspect the related wire harness. Look for chafed, pierced or partially broken wire.
• Refer to hotlines or technical service bulletins that may apply.
Refer to the appropriate Diesel Powertrain Diagnostic Manual for more information.
ECM DIAGNOSTIC TROUBLE CODES
IMPORTANT NOTE: Before replacing the ECM for a failed driver, control circuit or ground circuit, be sure to check
the related component/circuit integrity for failures not detected due to a double fault in the circuit. Most ECM driver/
control circuit failures are caused by internal failures to components (i.e. relays and solenoids) and shorted circuits
(i.e. sensor pull-ups, drivers and ground circuits). These faults are difficult to detect when a double fault has
occurred and only one DTC has set. If the DRBIIIT displays faults for multiple components (i.e.VSS, ECT, Batt
Temp, etc.) identify and check the shared circuits for possible problems before continuing (i.e. sensor grounds or
5-volt supply circuits). Refer to the appropriate wiring diagrams to identify shared circuits. Refer to the appropriate
Diesel Powertrain Diagnostic Manual for more information.
STANDARD PROCEDURE - ECM/SKIM PROGRAMMING - DIESEL

NOTE: Before replacing the ECM for a failed driver, control circuit or ground circuit, be sure to check the
related component/circuit integrity for failures not detected due to a double fault in the circuit. Most ECM
driver/control circuit failures are caused by internal component failures (i.e. relay and solenoids) and
shorted circuits (i.e. pull-ups, drivers and switched circuits). These failures are difficult to detect when a
double fault has occurred and only one DTC has set.
ECM/SKIM PROGRAMMING
When a ECM and the SKIM are replaced at the same time perform the following steps in order:
1. Program the new ECM.
2. Program the new SKIM.
3. Replace all ignition keys and program them to the new SKIM.
ECM/SKIM PROGRAMMING
When an ECM and the SKIM are replaced at the same time perform the following steps in order:
1. Program the new SKIM.
2. Program the new ECM.
PROGRAMMING THE ECM (Bosch)

1. To program the VIN, connect the scan tool and turn the ignition on.
2. Select Engine from the main menu. The scan tool will require the VIN to be entered before continuing.
3. Select ENTER to update the VIN. The scan tool will display the updated VIN.
4. If the engine is equipped with air conditioning, the ECM A/C function must be enabled. Enable the ECM A/C
function as follows:
• Using the scan tool select ENGINE, MISCELLANEOUS, then ENABLE/DISABLE A/C
• Push 1 to enable A/C, the scan tool screen should display A/C Activated.
PROGRAMMING THE SKIM

1. Turn the ignition switch on (transmission in park/neutral).
2. Use the scan tool and select THEFT ALARM, SKIM then MISCELLANEOUS.
3. Select ECM REPLACED (DIESEL ENGINE).
4. Program the vehicle four-digit PIN into SKIM.
5. Select COUNTRY CODE and enter the correct country.
NOTE: Be sure to enter the correct country code. If the incorrect country code is programmed into SKIM,
the SKIM must be replaced.
6. Select YES to update VIN (the SKIM will learn the VIN from the PCM).
7. Press ENTER to transfer the secret key (the PCM will send the secret key to the SKIM).
8. Program ignition keys to SKIM.
NOTE: If the ECM and the SKIM are replaced at the same time, all vehicle keys will need to be replaced and
programmed to the new SKIM.
PROGRAMMING IGNITION KEYS TO THE SKIM

1. Turn the ignition switch on (transmission in park/neutral).
2. Use the scan tool and select THEFT ALARM, SKIM then MISCELLANEOUS.
3. Select PROGRAM IGNITION KEY’S.
4. Enter secured access mode by entering the vehicle four-digit PIN.
NOTE: A maximum of eight keys can be learned to each SKIM. Once a key is learned to a SKIM it (the key)
cannot be transferred to another vehicle.
If ignition key programming is unsuccessful, the scan tool will display one of the following messages:
Programming Not Attempted - The scan tool attempts to read the programmed key status and there are no keys
programmed into SKIM memory.
Programming Key Failed (Possible Used Key From Wrong Vehicle) - SKIM is unable to program key due to one of
the following:
• faulty ignition key transponder
• ignition key is programmed to another vehicle.
8 Keys Already Learned, Programming Not Done - SKIM transponder ID memory is full.
5. Obtain ignition keys to be programmed from customer (8 keys maximum).
6. Using the scan tool, erase all ignition keys by selecting MISCELLANEOUS and ERASE ALL CURRENT IGN.
KEYS.
7. Program all ignition keys.
Learned Key In Ignition - Ignition key transponder ID is currently programmed in SKIM memory.
REMOVAL
1. Disconnect negative battery cable.
2. Disconnect ECM electrical connectors (1).
3. Remove ECM bracket to inner fender retaining nuts
(5).
4. Remove ECM and bracket assembly from vehicle.
5. Separate ECM from bracket.
INSTALLATION
1. Install ECM on bracket (3).
2. Position ECM and bracket assembly in vehicle.
3. Install ECM bracket to inner fender retaining nuts
(5).
4. Connect ECM electrical connectors (1).
5. Connect negative battery cable.
MODULE-FRONT CONTROL
DESCRIPTION
The Front Control Module (FCM) is a micro controller
based module located in the right front corner of the
engine compartment. The front control module mates
to the power distribution center to form the Integrated
Power Module (IPM). The IPM connects directly to the
battery and provides the primary means of circuit pro-
tection and power distribution for all vehicle electrical
systems. The FCM controls power to some of these
vehicle systems electrical and electromechanical loads
based on inputs received from hard wired switch
inputs and data received on the CAN bus circuit.
OPERATION
As messages are sent over the CAN bus circuit, the Front Control Module (FCM) reads these messages and con-
trols power to some of the vehicles electrical systems by completing the circuit to ground (low side driver) or com-
pleting the circuit to 12 volt power (high side driver). The following functions are controlled by the FCM:
• Air conditioning condenser cooling fan
• Daytime running lamps - if equipped
• Fog Lamps
• Front and rear hazard warning lamps
• Front turn signals
• Headlamps
• Horn
• Radiator fans
• Rear window defroster power and timing
• Stop, turn signal and tail lamps
• Windshield and liftgate wiper and washer systems
The FCM provides the following features for the above function:
• Acts as a link between the CAN bus network for critical powertrain, anti-lock brake systems, electronic stability
program systems and the network for body and interior modules.
• Controls the wipers based on messages on the CAN B bus from the rain sensor module (if equipped).
• Controls the adjustable pedal motor on non-memory equipped vehicles.
• Controls back-up lamps.
• Flashes lamps in response to turn signal, Remote Keyless Entry (RKE) and Vehicle Theft Security System
(VTSS) inputs.
• Illuminated approach feature that turns the headlamps on when the vehicle is unlocked with the Remote Key-
less Entry (RKE) transmitter.
• Minimizes voltage variations to the headlamps to extend bulb life and to equalize the light output from the
lamps, which might otherwise differ due to variations in wiring resistance.
• Monitors battery voltage and turns off non-essential functions such as the fog lamps, rear window defogger,
and heated seats if necessary to conserve battery power.
• Operates the high-beam headlamps at reduced intensity by pulse-width modulation of the power supply to pro-
vide the daytime running lamps.
• Protects the battery from discharge if the headlamps are left on, by automatically turning them off after eight
minutes.
• Provides ambient temperature sensor information.

• Provides A/C pressure transducer information.
• Provides brake fluid level information.
• Provides washer fluid level information.
• Provides the variable delay intermittent windshield and liftgate wiper time delay features, and the vehicle speed
sensitive windshield wiper delay variation.
• Sounds the horn in response to RKE and VTSS inputs.
• Turns off the horn in the event of excessively long operation that could otherwise damage the horn.
• Turns off the windshield washer motor after 10 seconds of continuous operation to protect the motor.
• Controls headlamp washers (if equipped).
• Provides wheel speed information on non-ABS equipped vehicles.
• Stores vehicle configuration data.

BODY VERIFICATION TEST – VER 1

Diagnostic Test
1. Perform Body Verification Test

1. Disconnect all jumper wires and reconnect all previously disconnected components and connectors.
2. Ensure that all accessories are turned off.
3. Ensure that the battery is fully charged. If the battery was disconnected for any reason, refer to (Refer to 8 -
ELECTRICAL/BATTERY SYSTEM - STANDARD PROCEDURE - BATTERY RECONNECTION) for accessory cal-
ibration procedures.
4. If the FCM has been replaced, the Pinion Factor MUST be programmed into the FCM. Refer to the scan tool
for program procedure.
5. Turn the ignition on.
6. With the scan tool, record and erase DTCs from all modules.
7. (Export only) If the Intrusion Transceiver Module (ITM) and/or Siren was replaced, select ITM from the from
the scan tool ECU view menu then “Misc. Functions” and perform the applicable replacement procedure.
8. Perform this step only if diagnosing faults related to the HVAC system.
• The Manual Temperature Control (MTC) is not on the Bus and not addressable with a scan tool.
Perform the following to clear DTCs from the MTC: 1. Turn the blower control on. 2. Press the A/C
mode switch down, turn the blower control to off, wait until both LEDs illuminate (approximately 5
seconds) and then release the A/C mode switch. 3. When the A/C status indicator begins flashing
DTCs, set the Mode switch to the floor position, simultaneously press the A/C mode switch and the
EBL mode switch down until both LEDs start flashing (approximately 5 seconds) and then release the
mode switches.
• For vehicles equipped with Automatic Temperature Control (ATC), if repairs were made to any of the
HVAC doors, linkage, door actuators, or door actuator circuits, run the actuator calibration function by
selecting the following from the scan tool menu: select HVAC, More Options, System Tests, Actuator
Calibration Test, and Start. Follow the directions displayed by the scan tool. Allow the test to run to
completion before proceeding.
• For vehicles equipped with MTC, if repairs were made to any of the HVAC doors, linkage, door actua-
tors, or door actuator circuits, run the door calibration function by performing the following: 1. Turn the
ignition on. 2. Turn the blower control to off. 3. Press the EBL mode switch down, turn the blower
control on, wait until the EBL LED starts flashing (approximately 5 seconds) and then release the
mode switch. Wait approximately 90 seconds for the calibration process to run to completion before
proceeding.
9. Turn the ignition off, wait 10 seconds, and then turn the ignition on.
10. Operate all functions of the system that caused the original concern. If a repair or module replacement was
done to the power windows, operate the motor fully down and then to the full up position and stall it for 2 sec-
onds.
11. With the scan tool, select ECU View and check for DTCs in the modules.
12. Perform this step only if diagnosing faults related to the MTC HVAC system.
NOTE: The A/C status indicator displays active DTCs when the EBL status indictor is not illuminated and
stored DTCs when the EBL status indicator is illuminated.
• Perform the following to read DTCs from the MTC: 1. Turn the blower control on. 2. Press the A/C
mode switch down, turn the blower control to off, wait until both LEDs illuminate (approximately 5
seconds) and then release the A/C mode switch. 3. Read the DTCs from the flashing A/C status
indicator.
Are DTCs present in any of the modules or is the original condition still present?
Yes >> The repair is not complete. Refer to the related category for the DTC or symptom that is still present.
No >> The repair is complete.
REMOVAL
formed anytime the battery has been disconnected.
STANDARD PROCEDURE).
2. Remove mounting fasteners.
3. Disconnect electrical connectors and remove Front
Control Module (FCM).
INSTALLATION
formed anytime the battery has been disconnected.
STANDARD PROCEDURE).
1. Position Front Control Module (FCM) and connect
electrical connectors.
2. Install and tighten mounting fasteners.
3. Connect battery negative cable.
MODULE-SEAT MEMORY
DESCRIPTION
NOTE: The scan tool standardization process
must be performed on the Memory Seat Module
(MSM) any time a new module is installed or the
existing module is reflashed.
The Memory Seat Module (MSM) is located under-

neath the driver seat, towards the front and on the
outboard side. It is used in conjunction with the other
modules in the memory system to recall the driver
seat to one of two preset seat positions (horizontal,
vertical, and recliner). The switch for the memory seat
programming and selection mounts on the driver door
trim panel. The memory system is able to store and
recall all driver side power seat positions, outside mir-
ror positions, power tilt/telescopic steering column
positions and power adjustable pedal position. The
system can be set for two different drivers. On vehi-
cles with a factory installed radio connected to the
Controller Area Network (CAN) data bus network, the memory system is also able to store and recall up to twelve
radio station presets (six AM and six FM), also for two drivers. The memory system will also store and recall the last
station listened to for each driver, even if it is not one of the twelve preset stations.
The memory system will automatically recall all of these settings when a button of the memory switch is depressed,
or when the doors are unlocked using the Remote Keyless Entry (RKE) transmitter (if the “RKE Linked to Memory”
feature is enabled). If the vehicle has more than two drivers the RKE transmitter recall of memory features can be
disabled. This is a customer programmable feature of the Electronic Vehicle Information Center (EVIC).
OPERATION
The Memory Seat Module (MSM) receives battery current through a 25 amp circuit breaker in the Power Distribution
Center (PDC) so that the memory system remains operational, regardless of the ignition switch position. When the
driver memory switch button is pushed, a resistance signal is sent to the MSM via the Controller Area Network
(CAN) bus circuit. The MSM is responsible for the 12v battery feed and ground path to the power seat adjuster
motor and other memory system components.
The MSM receives memory set/position switch input through the CAN bus circuit. The MSM also receives hard
wired input from the hall effect sensors, mounted on each of the driver power seat adjuster motors and the driver
side view mirror motor. The programmed software in the module allows it to know where the seat, adjustable ped-
als, and steering column tilt/telescope are located in its designed travel by a pulse count generated from the hall
effect sensors. This way, when the memory switch is depressed the module will power these components until the
correct preset location is achieved. The module will prevent the seat memory recall function from being initiated, if
the transmission gear selector lever is not in the Park position, or if the vehicle is moving. These inputs are mon-
itored over the Controller Area Network (CAN) bus circuit by the MSM.
A memory setting is saved by pressing the “set” button, then pressing either the memory “1” or “2” button within 5
seconds of pressing the “set” button.
A memory setting is recalled by pressing either the memory “1” or “2” button, or by pressing the unlock button on
a “linked” Remote Keyless Entry (RKE) transmitter.
For driver safety, memorized settings can not be recalled if the transmission is in a position other than Park or the
seat belt is latched.
The MSM performs the following functions:
• Positions the driver power seat (vertical, horizontal, and recliner positions).
• Positions the power adjustable pedals.
• Positions the power tilt/telescopic steering column positions.
• Sends the memory save or recall (#1 or #2) command over the CAN data bus circuit to the other memory
system components, radio station pre-sets and power mirror positions.
• Provides for “linking” the key FOBs to memory.
• Provides for the easy entry/exit feature.
• Provides the tilt mirrors in reverse feature.
When a memory button is pressed (#1 or #2) on the memory switch, the Driver Door Module (DDM) sends a recall
message to the MSM. The MSM will then position the memory system components to the preprogrammed location/
setting. When the Remote Keyless Entry (RKE) Transmitter button is pressed, depending on which transmitter (#1
or #2), the SKREEM (RKE Receiver) sends the recall request and FOB number (#1 or #2) data message. This RKE
transmitter function depends on if the MSM is programmed to trigger the recall (linked FOBs).
A memory setting is saved by pressing the “set “ button, then pressing either the memory “1” or “2” button within 5
seconds of pressing the “set” button.
A memory setting is recalled by pressing either the memory “1” or “2” button, or by pressing the unlock button on
a “linked” Remote Keyless Entry (RKE) transmitter.
For driver safety, memorized settings can not be recalled if the transmission is in any position other than park or the
seat belt is latched.
A key FOB is “linked” to a memory setting by pressing the “set” button and then pressing either the memory “1” or
“2” button within 5 seconds of pressing the set button, and then, with the key removed from the cylinder, pressing
the “lock” button on the selected key FOB.
The memory system “Easy Entry and Exit” feature provides the driver with more room to enter or exit the vehicle.
This is a customer programmable feature of the overhead console. When the seat is in a memorized position, it will
move rearward 55 millimeters or to the end of its travel, whichever occurs first, when the key is removed from the
ignition switch lock cylinder. A lock out zone of 60 millimeters has been established to protect rear passengers from
injury. If the memorized seat position is within the lock out zone the Easy Exit/Entry seat glide feature is disabled.
The seat will return to the memory position when the driver turns the vehicle’s ignition switch out of the LOCK
position.
The memory system 9Tilt in Reverse9 feature tilts the outside mirrors down a fixed, incremental angle when the
vehicle is shifted into REVERSE with the ignition switch in the RUN position. This feature provides the customer
with a better view of the ground and vehicle in the area of the rear tires when backing up. The mirrors move back
to their previous position when the vehicle is shifted out of REVERSE.
The memory system “learns” the seat and adjustable pedal motor maximum end positions when the motor reaches
the limit of travel in any direction and stalls. Subsequently, movement will stop just short of that position to avoid
extra stress on the motors and mechanisms. If the system learned a maximum position as a result of an obstruction,
as for instance if a large object was placed on the floor behind the seat, the system can relearn the “true” maximum
position through manually operating the power seat after the obstruction is removed.
NOTE: It is normal for the power accessories contained in the memory system to stop at the maximum
“learned” position and then continue to the “true” maximum position when the control switch is released
and then applied in the same direction a second time.
Certain functions and features of the memory system rely upon resources shared with other electronic modules in
the vehicle over the Controller Area Network (CAN) bus. The CAN bus allows the sharing of sensor information.
This helps to reduce wire harness complexity, internal controller hardware, and component sensor current loads. At
the same time, this system provides increased reliability, enhanced diagnostics, and allows the addition of many
new feature capabilities. For diagnosis of these electronic modules or of the CAN bus, the use of a scan tool and
the proper diagnostic information are needed.

MEMORY SEAT MODULE
In order to obtain conclusive testing of the memory system, the Controller Area Network (CAN) data bus, and all of
the electronic modules that provide inputs to, or receive outputs from the memory system components must be
checked. Any diagnosis of the memory system/module should begin with, the use of a scan tool and the
appropriate diagnostic service information.
Refer to the appropriate wiring information for complete circuit schematic or connector pin-out information.
NOTE: Vehicles equipped with the memory/heated seat option utilize a low voltage cut-off feature. This fea-
ture turns off the 12v power to the power seat system anytime vehicle voltage is below 11.7v. Be certain to
check the vehicle electrical system for proper voltage anytime the power seat system appears inoperative.
Before any testing of the power seat system is attempted, the battery should be fully-charged.
REMOVAL
2. Remove the driver seat cushion/cover (2) (Refer to
23 - BODY/SEATS/SEAT CUSHION COVER -
REMOVAL).
3. Pivot the module upward and disconnect the elec-
trical connectors (1).
4. Unsnap the memory seat module (4) from the side
brackets.
5. Pull the module rearward to remove it from the
front of the seat frame (3).
INSTALLATION
CAUTION: The Memory Seat Module (MSM) mounting tabs can be damaged during module installation. Use
care to properly align tabs to prevent binding that could result in tab breakage.
1. Place the Memory Seat Module (MSM) (4) into

position making sure the mounting tabs are prop-
erly aligned with the front bracket.
2. Push down on the rear of the MSM (4) snapping
the retaining clips into place in the side brackets.
3. Connect the MSM rear harness connectors (1).
4. Connect the MSM front harness connectors.
5. Install the driver seat cushion/cover (2) (Refer to 23
- BODY/SEATS/SEAT CUSHION COVER -
INSTALLATION).
6. Connect the battery negative cable.
7. Using an appropriate scan tool go to the MSM mis-
cellaneous functions and perform the standardiza-
tion routine.
8. Verify system and vehicle operation.
MODULE-STEERING CONTROL
DESCRIPTION
The Steering Control Module (SCM) is the module
located in the bottom of the Steering Column Control
Module (SCCM), retained by three screws, and is the
mating point for all the switches (remote radio
switches, horn, speed control, steering angle sensor,
tilt/telescopic switch, multi-function switch, clockspring)
located in the SCCM. The SCM is screwed directly to
the bottom of the multi-function switch. All the other
switches are mounted on top of the multi-function
switch.
OPERATION
The Steering Control Module (SCM) communicates via the Local Interconnect Network (LIN) serial data bus. This is
an ultra-low voltage serial data bus that allows the following components to communicate with the Controller Area
Network (CAN) B and C data buses.
• Steering Wheel Switches
• Horn
• Speed Control Switch
• Multi-function Switch
• Tilt/Telescoping Switch (if equipped)
• Steering Angle Sensor (if equipped with Electronic Stability Program (ESP))
• Steering Control Module (SCM)
The SCM changes the LIN communication to CAN communication and also stores Diagnostic Trouble Codes
(DTC’s) for the switches within the SCCM.
For removal and installation, disassembly and assembly of the SCCM, refer to the following:
NOTE: For Steering Column Module (SCM) removal and installation, refer to the disassembly and assembly
procedures for the Steering Column Control Module (SCCM).
• Removal of SCCM (Refer to 19 - STEERING/COLUMN/STEERING COLUMN CONTROL MODULE -

REMOVAL).
• Disassembly of SCCM (Refer to 19 - STEERING/COLUMN/STEERING COLUMN CONTROL MODULE - DIS-
ASSEMBLY).
• Assembly of SCCM (Refer to 19 - STEERING/COLUMN/STEERING COLUMN CONTROL MODULE - ASSEM-
BLY).
• Installation of the SCCM (Refer to 19 - STEERING/COLUMN/STEERING COLUMN CONTROL MODULE -
INSTALLATION).
The SCM is not serviceable and if found faulty, it must be replaced as a unit.
MODULE-POWERTRAIN CONTROL
DESCRIPTION
DESCRIPTION - PCM
The Powertrain Control Module (PCM) is located in
the engine compartment. The PCM is referred to as
NGC.
MODES OF OPERATION
As input signals to the Powertrain Control Module (PCM) change, the PCM adjusts its response to the output
devices. For example, the PCM must calculate different injector pulse width and ignition timing for idle than it does
for wide open throttle (WOT).
The PCM will operate in two different modes: Open Loop and Closed Loop.
During Open Loop modes, the PCM receives input signals and responds only according to preset PCM program-
ming. Input from the oxygen (O2S) sensors is not monitored during Open Loop modes.
During Closed Loop modes, the PCM will monitor the oxygen (O2S) sensors input. This input indicates to the PCM
whether or not the calculated injector pulse width results in the ideal air-fuel ratio. This ratio is 14.7 parts air-to-1
part fuel. By monitoring the exhaust oxygen content through the O2S sensor, the PCM can fine tune the injector
pulse width. This is done to achieve optimum fuel economy combined with low emission engine performance.
The fuel injection system has the following modes of operation:
• Ignition switch ON
• Engine start-up (crank)
• Engine warm-up
• Idle
• Cruise
• Acceleration
• Deceleration
• Wide open throttle (WOT)
• Ignition switch OFF
The ignition switch On, engine start-up (crank), engine warm-up, acceleration, deceleration and wide open throttle
modes are Open Loop modes. The idle and cruise modes, (with the engine at operating temperature) are Closed
Loop modes.
IGNITION SWITCH (KEY-ON) MODE

This is an Open Loop mode. When the fuel system is activated by the ignition switch, the following actions occur:
• The PCM determines atmospheric air pressure from the MAP sensor input to determine basic fuel strategy.
• The PCM monitors the engine coolant temperature sensor input. The PCM modifies fuel strategy based on this
input.
• Intake manifold air temperature sensor input is monitored.
• Throttle position sensor (TPS) is monitored.
• The auto shutdown (ASD) relay is energized by the PCM for approximately three seconds.
• The fuel pump is energized through the fuel pump relay by the PCM. The fuel pump will operate for approx-
imately three seconds unless the engine is operating or the starter motor is engaged.
• The O2S sensor heater element is energized via the O2S relays. The O2S sensor input is not used by the
PCM to calibrate air-fuel ratio during this mode of operation.
ENGINE START-UP MODE

This is an Open Loop mode. The following actions occur when the starter motor is engaged.
The PCM receives inputs from:
• Battery voltage
• Engine coolant temperature sensor
• Crankshaft position sensor
• Intake manifold air temperature sensor
• Manifold absolute pressure (MAP) sensor
• Throttle position sensor (TPS)
• Starter motor relay
• Camshaft position sensor signal
The PCM monitors the crankshaft position sensor. If the PCM does not receive a crankshaft position sensor signal
within approximately 3 seconds of cranking the engine, it will shut down the fuel injection system.
The fuel pump is activated by the PCM through the fuel pump relay.
Voltage is applied to the fuel injectors with the ASD relay via the PCM. The PCM will then control the injection
sequence and injector pulse width by turning the ground circuit to each individual injector on and off.
The PCM determines the proper ignition timing according to input received from the crankshaft position sensor.
ENGINE WARM-UP MODE

This is an Open Loop mode. During engine warm-up, the PCM receives inputs from:
• Battery voltage
• Park/neutral switch (gear indicator signal—auto. trans. only)
• Air conditioning select signal (if equipped)
• Air conditioning request signal (if equipped)
Based on these inputs the following occurs:
• Voltage is applied to the fuel injectors with the ASD relay via the PCM. The PCM will then control the injection
• The PCM adjusts engine idle speed through the idle air control (IAC) motor and adjusts ignition timing.
• The PCM operates the A/C compressor clutch through the clutch relay. This is done if A/C has been selected
by the vehicle operator and requested by the A/C thermostat.
• When engine has reached operating temperature, the PCM will begin monitoring O2S sensor input. The sys-
tem will then leave the warm-up mode and go into closed loop operation.
IDLE MODE
When the engine is at operating temperature, this is a Closed Loop mode. At idle speed, the PCM receives inputs
from:
• Battery voltage
• Battery voltage
• Oxygen sensors
Based on these inputs, the following occurs:
• Voltage is applied to the fuel injectors with the ASD relay via the PCM. The PCM will then control injection
• The PCM monitors the O2S sensor input and adjusts air-fuel ratio by varying injector pulse width. It also
adjusts engine idle speed through the idle air control (IAC) motor.
• The PCM adjusts ignition timing by increasing and decreasing spark advance.
• The PCM operates the A/C compressor clutch through the clutch relay. This happens if A/C has been selected
CRUISE MODE
When the engine is at operating temperature, this is a Closed Loop mode. At cruising speed, the PCM receives
inputs from:
• Battery voltage
• Oxygen (O2S) sensors
Based on these inputs, the following occurs:
• Voltage is applied to the fuel injectors with the ASD relay via the PCM. The PCM will then adjust the injector
pulse width by turning the ground circuit to each individual injector on and off.
• The PCM monitors the O2S sensor input and adjusts air-fuel ratio.
• The PCM adjusts ignition timing by turning the ground path to the coils on and off.
• The PCM operates the A/C compressor clutch through the clutch relay. This happens if A/C has been selected
ACCELERATION MODE
This is an Open Loop mode. The PCM recognizes an abrupt increase in throttle position or MAP pressure as a
demand for increased engine output and vehicle acceleration. The PCM increases injector pulse width in response
to increased throttle opening.
DECELERATION MODE
When the engine is at operating temperature, this is an Open Loop mode. During hard deceleration, the PCM
receives the following inputs.
• Battery voltage
• Vehicle speed
If the vehicle is under hard deceleration with the proper rpm and closed throttle conditions, the PCM will ignore the
oxygen sensor input signal. The PCM will enter a fuel cut-off strategy in which it will not supply a ground to the
injectors. If a hard deceleration does not exist, the PCM will determine the proper injector pulse width and continue
injection.
The PCM adjusts ignition timing by turning the ground path to the coils on and off.
WIDE OPEN THROTTLE MODE

This is an Open Loop mode. During wide open throttle operation, the PCM receives the following inputs.
• Battery voltage
During wide open throttle conditions, the following occurs:
• Voltage is applied to the fuel injectors with the ASD relay via the PCM. The PCM will then control the injection
sequence and injector pulse width by turning the ground circuit to each individual injector on and off. The PCM
ignores the oxygen sensor input signal and provides a predetermined amount of additional fuel. This is done
by adjusting injector pulse width.
• The PCM adjusts ignition timing by turning the ground path to the coil on and off.
IGNITION SWITCH OFF MODE

When ignition switch is turned to OFF position, the PCM stops operating the injectors, ignition coil, ASD relay and
fuel pump relay.
5 VOLT SUPPLIES
Two different Powertrain Control Module (PCM) five volt supply circuits are used; primary and secondary.
IGNITION CIRCUIT SENSE

This circuit ties the ignition switch to the Powertrain Control Module (PCM).
POWER GROUNDS
The Powertrain Control Module (PCM) has 2 main grounds. Both of these grounds are referred to as power
grounds. All of the high-current, noisy, electrical devices are connected to these grounds as well as all of the sensor
returns. The sensor return comes into the sensor return circuit, passes through noise suppression, and is then con-
nected to the power ground.
The power ground is used to control ground circuits for the following PCM loads:
• Generator field winding
• Fuel injectors
• Ignition coil(s)
• Certain relays/solenoids
• Certain sensors
SENSOR RETURN
The Sensor Return circuits are internal to the Powertrain Control Module (PCM).
Sensor Return provides a low–noise ground reference for all engine control system sensors. Refer to Power
Grounds for more information.
OPERATION
OPERATION - PCM
1. Also refer to Modes of Operation.
The PCM operates the fuel system. The PCM is a pre-programmed, triple microprocessor digital computer. It reg-
ulates ignition timing, air-fuel ratio, emission control devices, charging system, certain transmission features, speed
control, air conditioning compressor clutch engagement and idle speed. The PCM can adapt its programming to
meet changing operating conditions.
The PCM receives input signals from various switches and sensors. Based on these inputs, the PCM regulates
various engine and vehicle operations through different system components. These components are referred to as
Powertrain Control Module (PCM) Outputs. The sensors and switches that provide inputs to the PCM are consid-
ered Powertrain Control Module (PCM) Inputs.
The PCM adjusts ignition timing based upon inputs it receives from sensors that react to: engine rpm, manifold
absolute pressure, engine coolant temperature, throttle position, transmission gear selection (automatic transmis-
sion), vehicle speed and the brake switch.
The PCM adjusts idle speed based on inputs it receives from sensors that react to: throttle position, vehicle speed,
transmission gear selection, engine coolant temperature and from inputs it receives from the air conditioning clutch
switch and brake switch.
Based on inputs that it receives, the PCM adjusts ignition coil dwell. The PCM also adjusts the generator charge
rate through control of the generator field and provides speed control operation.
NOTE: PCM Inputs:
• A/C request
• Auto shutdown (ASD) sense
• Battery temperature
• Battery voltage
• Brake switch
• J1850 bus circuits
• Data link connections for scan tool
• Five volts (primary)
• Five volts (secondary)
• Fuel level
• Generator (battery voltage) output
• Ignition circuit sense (ignition switch in on/off/crank/run position)
• Leak detection pump (switch) sense (if equipped)

• Oil pressure
• Overdrive/override switch
• Oxygen sensors
• Park/neutral switch (auto. trans. only)
• Power ground
• Sensor return
• Signal ground
• Speed control multiplexed single wire input
• Throttle position sensor
• Transmission governor pressure sensor
• Transmission temperature sensor
• Vehicle speed (from ABS module)
NOTE: PCM Outputs:
• A/C clutch relay

• Auto shutdown (ASD) relay
• J1850 (+/-) circuits for: speedometer, voltmeter, fuel gauge, oil pressure gauge/lamp, engine temp. gauge and
speed control warn. lamp
• Data link connection for scan tool
• EGR valve control solenoid (if equipped)
• EVAP canister purge solenoid
• Fuel injectors
• Fuel pump relay
• Generator field driver (-)
• Generator field driver (+)
• Generator lamp (if equipped)
• Ignition coil
• Natural Vacuum Leak detection Switch
• Malfunction indicator lamp (Check engine lamp). Driven through J1850 circuits.
• Overdrive indicator lamp (if equipped). Driven through J1850 circuits.
• Oxygen sensor heater relays (if equipped).
• Radiator cooling fan relay (pulse width modulated)
• Speed control source
• Speed control vacuum solenoid
• Speed control vent solenoid
• Tachometer (if equipped). Driven through J1850 circuits.
• Transmission convertor clutch circuit
• Transmission 3–4 shift solenoid
• Transmission relay
• Transmission temperature lamp (if equipped)
• Transmission variable force solenoid
5 VOLT SUPPLIES
Primary 5-volt supply:
• supplies the required 5 volt power source to the Crankshaft Position (CKP) sensor.
• supplies the required 5 volt power source to the Camshaft Position (CMP) sensor.
• supplies a reference voltage for the Manifold Absolute Pressure (MAP) sensor.
• supplies a reference voltage for the Throttle Position Sensor (TPS) sensor.
Secondary 5-volt supply:
• supplies the required 5 volt power source to the oil pressure sensor.
• supplies the required 5 volt power source for the Vehicle Speed Sensor (VSS) (if equipped).
• supplies the 5 volt power source to the transmission pressure sensor (if equipped with an RE automatic trans-
mission).
OPERATION - IGNITION CIRCUIT SENSE

The ignition circuit sense input tells the PCM the ignition switch has energized the ignition circuit.
Battery voltage is also supplied to the PCM through the ignition switch when the ignition is in the RUN or START
position. This is referred to as the 9ignition sense9 circuit and is used to 9wake up9 the PCM.

NGC POWERTRAIN VERIFICATION TEST VER - 1

For the Engine circuit diagram (Refer to 9 - ENGINE - SCHEMATICS AND DIAGRAMS).
Diagnostic Test
1. NGC POWERTRAIN VERIFICATION TEST VER - 1

NOTE: 1. If this vehicle is equipped with an Electron Throttle Control system, and the APP Sensors, PCM, or
Throttle Body Assembly have been replaced, use a scan tool to perform the ETC RELEARN function.
NOTE: 2. If the PCM or FCM have been replaced, the Pinion Factor MUST be programmed into the FCM.
While programming the Pinion Factor into the FCM the scan tool will send the Pinion Factor information to
the PCM at the same time. Refer to the scan tool for program procedure.
NOTE: 3. If the PCM has been replaced and the correct VIN and mileage have not been programmed, a DTC
will set in the ABS Module, Airbag Module and the SKIM.
NOTE: 4. If the vehicle is equipped with a Sentry Key Immobilizer System, Secret Key data must be updated.
Refer to the Service Information for the PCM, SKIM and the Transponder (ignition key) for programming
information.
5. Inspect the vehicle to ensure that all components related to the repair are properly installed and connected.
6. Inspect the engine oil for fuel contamination. Replace the oil and filter as necessary.
7. Attempt to start the engine.
8. If the No Start condition is still present, refer to the Engine Electrical Diagnostic list and perform the diagnostic
testing as necessary, refer to any Technical Service Bulletins that may apply.
9. Run the engine for one warm-up cycle to verify operation.
10. With the scan tool, confirm that no DTCs are present and that all components are functioning properly.
NOTE: The PCM can detect and compensate for variances in the engine and its components. To learn these
variations, the PCM uses the input of the actual crankshaft rotation pattern and ideal crankshaft rotation
pattern that has been calibrated into the PCM. The PCM then compares the two patterns. The variation
between the two values is the Adaptive Numerator. If the Adaptive Numerator is not learned by the PCM, the
misfire monitor will not run and the Multi-Cylinder Displacement System (MDS) will not operate. Without
MDS operation, the customer will experience decreased fuel economy. If the customer experiences decrease
fuel economy or after any repair use the scan tool to ensure that the Adaptive Numerator is learned.
Are any DTCs or symptoms remaining?
Yes >> Check for any related Technical Service Bulletins and/or refer to the appropriate Diagnostic Procedure.

Diagnostic Test

NOTE: 1. If this vehicle is equipped with a Electronic Throttle Control system, and the APP Sensors, PCM,
or Throttle Body Assembly have been replaced, use a scan tool to perform the ETC RELEARN function.
NOTE: 2. If the PCM or FCM have been replaced, the Pinion Factor MUST be programmed into the FCM.
While programming the Pinion Factor into the FCM the scan tool will send the Pinion Factor information to
the PCM at the same time. Refer to the scan tool for program procedure.
information.
5. Inspect the vehicle to make sure that all components related to the repair are properly installed and connected.
6. With a scan tool, clear DTCs and Reset Memory all engine values.
7. Run the engine for one warm-up cycle to verify proper operation.
8. Road test the vehicle. Use all accessories that may be related to this repair.
9. With the scan tool, confirm that no DTC’s are present and that all components are functioning properly.
10. If this test is being performed after a No Trouble Code test, verify the symptom is no longer present.
Yes >> Check for any related Technical Service Bulletins and/or refer to the appropriate Diagnostic Procedure.

Diagnostic Test

1. If this vehicle is equipped with an Electronic Throttle Control system, and the APP Sensors, PCM, or Throttle
Body Assembly has been replaced use a scan tool to perform the ETC RELEARN function.
NOTE: 2. After completing the Powertrain Verification Test the Transmission Verification Test must be per-
formed.
information.
5. Inspect the vehicle to make sure that all components related to the repair are properly installed and connected.
6. With the scan tool, clear DTCs.
7. Perform generator output test. Refer to the appropriate service information as necessary.
8. Start the engine and set engine speed to 2000 RPM for at least thirty seconds.
9. Cycle the ignition key off and on.
10. With the scan tool, read the DTCs.
Yes >> Check for any Technical Service Bulletins and/or refer to the appropriate Diagnostic Procedure.

Diagnostic Test

NOTE: If this vehicle is equipped with an Electronic Throttle Control system, and the APP Sensors, PCM, or
Throttle Body Assembly have been replaced, use the scan tool to perform the ETC RELEARN function.
formed.
information.
5. Inspect the vehicle to make sure that all engine components are properly installed and connected.
6. Connect the scan tool to the data link connector and erase all codes.
7. Turn the speed control ON (if equipped, cruise light will be on).
8. Depress and release the SET Switch when the vehicle speed is greater than 35 MPH. The speed control should
engage and hold the selected speed.
9. Press and hold the RESUME/ACCEL Switch. The vehicle speed should increase by at least 2 MPH.
10. Press and hold the COAST switch. The vehicle speed should decrease.
11. Using caution, press and release the brake pedal. The speed control should disengage.
12. Bring the vehicle speed back up to 35 MPH.
13. Press the RESUME/ACCEL switch. The speed control should resume the previously set speed.
14. Hold down the SET switch. The vehicle should decelerate.
15. Make sure vehicle speed is greater than 35 mph and release the SET Switch. The vehicle should adjust and set
a new vehicle speed.
16. Press and release the CANCEL switch. The speed control should disengage.
17. Bring the vehicle speed back up above 35 mph and engage speed control.
18. Turn the Speed Control Off. (Cruise light will be off). The speed control should disengage.
NOTE: OVERSHOOT/UNDERSHOOT FOLLOWING SPEED CONTROL SET.
20. If the vehicle operator repeatedly presses and releases the SET button with their foot off of the accelerator
(referred to as 9lift foot set9), the vehicle may accelerate and exceed the desired set speed by up to 5 mph (8 km/h).
21. It may also decelerate to less than the desired set speed, before finally achieving the desired set speed.
22. The Speed Control System has an adaptive strategy that compensates for vehicle-to-vehicle variations in speed
control cable lengths.
23. When the speed control is set with the vehicles operators foot off of the accelerator pedal, the speed control
thinks there is excessive speed control cable slack and adapts accordingly.
24. If the 9lift foot sets9 are continually used, a speed control overshoot/undershoot condition will develop.
25. To 9unlearn9 the overshoot/undershoot condition, the vehicle operator has to press and release the set button
while maintaining the desired set speed using the accelerator pedal (not decelerating or accelerating).
26. Then turn the cruise control switch to the OFF position (or press the CANCEL button if equipped) after waiting
10 seconds.
27. This procedure must be performed approximately 10-15 times to completely unlearn the overshoot/undershoot
condition.
Did the Speed Control pass the above test?
Yes >> Repair is complete.
No >> Check for any related Technical Service Bulletins and/or refer to the appropriate Diagnostic Procedure.

Diagnostic Test

formed.
information.
NOTE: 4. If this vehicle is equipped with an Electronic Throttle Control system, and the APP Sensors, PCM,
or Throttle Body Assembly have been replaced, use the scan tool to perform the ETC RELEARN function.
NOTE: 5. When replacing an O2 Sensor, the PCM RAM memory must be cleared, either by disconnecting the
PCM C-1 connector or momentarily disconnecting the Battery negative terminal.
6. The NGC learns the characteristics of each O2 heater element and these old values should be cleared when
installing a new O2 sensor. The customer may experience driveability issues if this is not performed.
7. Inspect the vehicle to ensure that all engine components are properly installed and connected. Reassemble and
reconnect components as necessary.
8. Connect the scan tool to the data link connector.
9. Make sure the fuel tank has at least a quarter tank of fuel. Turn off all accessories.
10. If the Catalyst was replaced, with the scan tool go to the Miscellaneous Menu Option 9Catalyst Replaced9 and
press enter.
11. If a Comprehensive Component DTC was repaired, perform steps 12 - 14. If a Major OBDII Monitor DTC was
repaired skip those steps and continue verification.
12. After the ignition has been off for at least 10 seconds, restart the vehicle and run 2 minutes.
13. With the scan tool, monitor the appropriate pre-test enabling conditions until all conditions have been met. Once
the conditions have been met, switch screen to the appropriate OBDII monitor, (Audible beeps when the monitor is
running).
14. If the repaired OBDII trouble code has reset or was seen in the monitor while on the road test, the repair is not
complete. Check for any related technical service bulletins or flash updates and return to Engine Electrical Diag-
nostic List.
15. If the conditions cannot be duplicated, erase all DTCs with the Scan Tool.
16. If another DTC has set, return to the Engine Electrical Diagnostic List and follow the path specified for that DTC.
Did the OBDII Monitor run successfully and has the Good Trip Counter changed to one or more?
Yes >> Repair is complete.
No >> Check for any related Technical Service Bulletins and/or refer to the appropriate Diagnostic Procedure.

Diagnostic Test

1. Install the Miller Tool #8404 Evaporative Emission Leak Detector (EELD) according to the instructions in the pre-
vious DTC table.
2. Set the smoke/air control switch to AIR.
3. Insert the tester’s AIR supply tip (clear hose) into the appropriate calibration orifice on the tester’s control panel
(based on DTC leak size).
4. Press the remote smoke/air start button.
5. Position the red flag on the air flow meter so it is aligned with the indicator ball.
6. When the calibration is complete, release the remote button. The EELD flow meter is now calibrated in liters per
minute to the size of leak indicated by the DTC set in the PCM.
7. Install the service port adapter #8404-14 on the vehicle’s service port.
8. Connect the Air supply hose from the EELD to the vehicle.
9. Press the remote button to activate AIR flow.
NOTE: 10. Larger volume fuel tanks, lower fuel levels or if the vehicle is equipped with a Flow Management
Valve may indicate high flow and will require 4 to 5 minutes to fill.
11. Compare the flow meter indicator ball reading to the red flag.
12. ABOVE the red flag indicates a leak present.
13. BELOW the red flag indicates a sealed system.
NOTE: If this vehicle is equipped with an Electronic Throttle Control system, and the APP Sensors, PCM, or
Throttle Body Assembly have been replaced, use the scan tool to perform the ETC RELEARN function.
15. If the indicator ball shows a leak present, perform the smoke test indicated in the previous test and identify the
leak and repair. Perform this verification test when the repair is complete.
Did the indicator ball indicate the a leak is present?
Yes >> Repeat the DTC test to identify the leak and repair.
STANDARD PROCEDURE
TCM QUICK LEARN - 42RLE Only
The quick learn procedure requires the use of the appropriate scan tool.
This program allows the electronic transmission system to recalibrate itself. This will provide the proper transmission
operation. The quick learn procedure should be performed if any of the following procedures are performed:
• Transmission Assembly Replacement
• Transmission Control Module Replacement
• Solenoid Pack Replacement
• Clutch Plate and/or Seal Replacement
• Valve Body Replacement or Recondition
To perform the Quick Learn Procedure, the following conditions must be met:
• The brakes must be applied

• The engine speed must be above 500 rpm
• The throttle angle (TPS) must be less than 3 degrees
• The shift lever position must stay in PARK until prompted to shift to overdrive
• The shift lever position must stay in overdrive after the Shift to Overdrive prompt until the scan tool indicates
the procedure is complete.
• The calculated oil temperature must be above 60° and below 200°
TCM ADAPTATION - NAG1 Only

The adaptation procedure requires the use of the appropriate scan tool. This program allows the electronic trans-
mission system to re-calibrate itself. This will provide the proper baseline transmission operation. The adaptation
procedure should be performed if any of the following procedures are performed:
• Electrohydraulic Unit Replacement or Recondition
1. With the scan tool, reset the Transmission adaptives. Resetting the adaptives will set the adaptives to factory
settings.
NOTE: Perform the Coast Down Adaptations first. The Transmission Temperature must be greater than 60°C
(140°F) and less than 70°C (158°F). Failure to stay within these temperature ranges will void the procedure.
2. Drive the vehicle until the transmission temperature is in the specified range.
3. Perform 4 to 5 coast downs from 5th to 4th gear and then 4th to 3rd gear.
NOTE: For Upshift adaptation, the Transmission temperature must be greater than 60°C (140°F) and less
than 100°C (212°F). Failure to stay within these temperature ranges will void this procedure.
4. From a stop, moderately accelerate the vehicle and obtain all forward gear ranges while keeping the Engine
RPM below 1800 RPM. Repeat this procedure 4 to 5 times.
5. Obtaining 5th gear may be difficult at 1800 RPM. Allow the transmission to shift into 5th gear at a higher RPM
then lower the RPM to 1800 and perform manual shifts between 4th and 5th gears using the shift lever.
6. The TCM will store the adaptives every 10 minutes. After completion of the adaptation procedure make sure the
vehicle stays running for at least 10 minutes.
7. It is possible to manually store the adaptives under the 10 minute time frame using the scan tool Store Adaptives
procedure.
REMOVAL
USE THE SCAN TOOL TO REPROGRAM THE NEW POWERTRAIN CONTROL MODULE (PCM) WITH THE
VEHICLES ORIGINAL IDENTIFICATION NUMBER (VIN) AND THE VEHICLES ORIGINAL MILEAGE. IF THIS
STEP IS NOT DONE, A DIAGNOSTIC TROUBLE CODE (DTC) MAY BE SET.
To avoid possible voltage spike damage to PCM, ignition key must be off, and negative battery cable must be dis-
connected before unplugging PCM connectors.
1. Disconnect negative battery cable.
2. Remove PCM bracket-to-body mounting bolt.

3. Remove assembly from vehicle.
4. Unlock and disconnect the electrical connectors
from PCM.
5. Remove bracket from PCM.

6. Remove the rubber bumper from PCM.
INSTALLATION
USE THE SCAN TOOL TO REPROGRAM THE NEW POWERTRAIN CONTROL MODULE (PCM) WITH THE
VEHICLES ORIGINAL IDENTIFICATION NUMBER (VIN) AND THE VEHICLES ORIGINAL MILEAGE. IF THIS
STEP IS NOT DONE, A DIAGNOSTIC TROUBLE CODE (DTC) MAY BE SET.
1. Install rubber bumper to PCM back.
2. Check pins in electrical connectors for damage.
Repair as necessary.
3. Install electrical connectors to PCM.
4. Install mounting bracket to PCM.
5. Install assembly to body. Install bolt and tighten 9

N·m (80 in. lbs.) torque.
6. Connect negative cable to battery.

7. Use the scan tool to reprogram new PCM with vehicles original Identification Number (VIN) and original vehicle
mileage.
MODULE-TRANSMISSION CONTROL
DESCRIPTION
TRANSMISSION CONTROL MODULE - 42RLE
The Transmission Control Module (TCM) is a sub-
module within the Powertrain Control Module (PCM).
The Powertrain Control Module (PCM) is located in
the right rear of the engine compartment, just in front
of the windshield.
TRANSMISSION CONTROL MODULE - NAG1

The electronic control system consists of various com-
ponents providing inputs to the transmission control
module (TCM). The TCM monitors transmission sen-
sors, shift lever position, and bus messages to deter-
mine transmission shift strategy. After shift strategies
are determined, the TCM controls the actuation of
transmission solenoids, which controls the routing of
hydraulic fluid within the transmission, by moving a
sequence of four valves to make a shift occur.
The NAG1 electronic transmission has a fully adaptive
control system. The system performs its functions
based on continuous real-time sensor feedback infor-
mation. In addition the TCM receives information from
the PCM (engine management) and ABS (chassis sys-
tems) controllers over the CAN bus. The CAN bus is a
high-speed communication bus that allows real time
control capability between various controllers. Most
messages are sent every 20 milliseconds. This means
critical information can be shared between the trans-
mission, engine, and ABS controllers. The CAN bus is
a two wire bus with a CAN Bus (+) circuit and a CAN
Bus (-) circuit. These circuits are twisted pairs in the
harness to reduce the potential of radio and noise interference.
The transmission control system automatically adapts to changes in engine performance, vehicle speed, and trans-
mission temperature variations to provide consistent shift quality. The control system ensures that clutch operation
during up-shifting and downshifting is more responsive without increased harshness. The TCM activates the sole-
noid valves and moves valves in the valve body to achieve the necessary gear changes. The required pressure
level is calculated from the load condition, engine speed. Vehicle speed (from ABS module) and transmission oil
temperature, matched to the torque to be transmitted. The TCM is located under the left side of the instrument panel
for left hand drive vehicles. For right hand drive vehicles, the TCM is located in the mirrored location under the right
side of the instrument panel.
OPERATION
TRANSMISSION CONTROL MODULE - 42RLE
The Transmission Control Module (TCM) controls all electronic operations of the transmission. The TCM receives
information regarding vehicle operation from both direct and indirect inputs, and selects the operational mode of the
transmission. Direct inputs are hard wired to, and used specifically by the TCM. Indirect inputs are shared with the
TCM via the vehicle communication bus.
Some examples of direct inputs to the TCM are:
• Battery (B+) voltage
• Ignition “ON” voltage
• Transmission Control Relay (Switched B+)
• Throttle Position Sensor
• Crankshaft Position Sensor
• Transmission Range Sensor
• Pressure Switches
• Transmission Temperature Sensor
• Input Shaft Speed Sensor
• Output Shaft Speed Sensor
• Line Pressure Sensor
Some examples of indirect inputs to the TCM are:
• Engine/Body Identification
• Manifold Pressure
• Target Idle
• Torque Reduction Confirmation
• Engine Coolant Temperature
• Ambient/Battery Temperature
• Scan Tool Communication
Based on the information received from these various inputs, the TCM determines the appropriate shift schedule
and shift points, depending on the present operating conditions and driver demand. This is possible through the
control of various direct and indirect outputs.
Some examples of TCM direct outputs are:
• Transmission Control Relay
• Solenoids
• Torque Reduction Request
Some examples of TCM indirect outputs are:
• Transmission Temperature (to PCM)
• PRNDL Position (to cluster/CCN)
In addition to monitoring inputs and controlling outputs, the TCM has other important responsibilities and functions:
• Storing and maintaining Clutch Volume Indexes (CVI)
• Storing and selecting appropriate Shift Schedules
• System self-diagnostics
• Diagnostic capabilities (with scan tool)
NOTE: If the TCM has been replaced, the “Quick Learn Procedure” must be performed. (Refer to 8 - ELEC-
TRICAL/ELECTRONIC CONTROL MODULES/TRANSMISSION CONTROL MODULE - STANDARD PROCE-
DURE)
BATTERY FEED
A fused, direct battery feed to the TCM is used for continuous power. This battery voltage is necessary to retain
memory in the TCM. When the battery (B+) is disconnected, this memory is lost. When the battery (B+) is restored,
this memory loss is detected by the TCM and a Diagnostic Trouble Code (DTC) is set.
CLUTCH VOLUME INDEXES (CVI)

An important function of the TCM is to monitor Clutch
Volume Indexes (CVI). CVIs represent the volume of
fluid needed to compress a clutch pack.
The TCM monitors gear ratio changes by monitoring
the Input and Output Speed Sensors. The Input, or
Turbine Speed Sensor sends an electrical signal to
the TCM that represents input shaft rpm. The Output
Speed Sensor provides the TCM with output shaft
speed information.
By comparing the two inputs, the TCM can determine
transmission gear position. This is important to the
CVI calculation because the TCM determines CVIs by
monitoring how long it takes for a gear change to
occur.
Gear ratios can be determined by using the Scan Tool
and reading the Input/Output Speed Sensor values in
the “Monitors” display. Gear ratio can be obtained by
dividing the Input Speed Sensor value by the Output
Speed Sensor value.
For example, if the input shaft is rotating at 1000 rpm
and the output shaft is rotating at 500 rpm, then the
TCM can determine that the gear ratio is 2:1. In direct drive (3rd gear), the gear ratio changes to 1:1. The gear ratio
changes as clutches are applied and released. By monitoring the length of time it takes for the gear ratio to change
following a shift request, the TCM can determine the volume of fluid used to apply or release a friction element.
The volume of transmission fluid needed to apply the friction elements are continuously updated for adaptive con-
trols. As friction material wears, the volume of fluid need to apply the element increases.
Certain mechanical problems within the input clutch assembly can cause inadequate or out-of-range element vol-
umes. Also, defective Input/Output Speed Sensors and wiring can cause these conditions. The following chart iden-
tifies the appropriate clutch volumes and when they are monitored/updated:
CLUTCH VOLUMES
Clutch When Updated Proper Clutch Volume
L/R 2-1 or 3-1 downshift 45 to 134
2C 3-2 kickdown shift 25 to 85
OD 2-3 upshift 30 to 100
4C 3-4 upshift 30 to 85
UD 4-3 kickdown shift 30 to 100
SHIFT SCHEDULES
As mentioned earlier, the TCM has programming that allows it to select a variety of shift schedules. Shift schedule
selection is dependent on the following:
• Shift lever position
• Throttle position
• Engine load
• Fluid temperature
• Software level
As driving conditions change, the TCM appropriately adjusts the shift schedule. Refer to the following chart to deter-
mine the appropriate operation expected, depending on driving conditions.
Schedule Condition Expected Operation

Extreme Cold Oil temperature below -16° F -Park, Reverse, Neutral and 1st and
3rd gear only in D position, 2nd
gear only in Manual 2 or L
-No EMCC
Super Cold Oil temperature between -12° F and - Delayed 2-3 upshift
10° F - Delayed 3-4 upshift
- Early 4-3 coastdown shift
- High speed 4-2, 3-2, 2-1 kickdown
shifts are prevented
-Shifts at high throttle openings willl
be early.
- No EMCC
Cold Oil temperature between 10° F and -Shift schedule is the same as
36° F Super Cold except that the 2-3
upshifts are not delayed.
Warm Oil temperature between 40° F and - Normal operation (upshift,
80° F kickdowns, and coastdowns)
- No EMCC
Hot Oil temperature between 80° F and - Normal operation (upshift,
240° F kickdowns, and coastdowns)
- Normal EMCC operation
Overheat Oil temperature above 240° F or - Delayed 2-3 upshift
engine coolant temperature above - Delayed 3-4 upshift
244° F
- 3rd gear FEMCC from 30-48 mph
- 3rd gear PEMCC above 35 mph
- Above 25 mph the torque
converter will not unlock unless the
throttle is closed or if a wide open
throttle 2nd PEMCC to 1 kickdown
is made
TRANSMISSION CONTROL MODULE - NAG1

The transmission control module (TCM) determines the current operating conditions of the vehicle and controls the
shifting process for shift comfort and driving situations. It receives this operating data from sensors and broadcast
messages from other modules.
The TCM uses inputs from several sensors that are directly hardwired to the controller and it uses several indirect
inputs that are used to control shifts. This information is used to actuate the proper solenoids in the valve body to
achieve the desired gear.
The shift lever assembly (SLA) has sensors that are monitored by the TCM to calculate shift lever position. The
reverse light switch, an integral part of the SLA, controls the reverse light relay control circuit. The Brake/Transmis-
sion Shift Interlock (BTSI) solenoid and the park lockout solenoid (also part of the SLA) are controlled by the TCM.
The PCM and ABS broadcast messages over the controller area network (CAN) bus for use by the TCM. The TCM
uses this information, with other inputs, to determine the transmission operating conditions.
The TCM:
• determines the momentary operating conditions of the vehicle.
• controls all shift processes.
• considers shift comfort and the driving situation.

The TCM controls the solenoid valves for modulating shift pressures and gear changes. Relative to the torque being
transmitted, the required pressures are calculated from load conditions, engine rpm, vehicle speed, and ATF tem-
perature.
The following functions are contained in the TCM:
• Shift Program
• Downshift Safety
• Torque Converter Lock-Up Clutch.
• Adaptation.
The TCM continuously checks for electrical problems, mechanical problems, and some hydraulic problems. When a
problem is sensed, the TCM stores a diagnostic trouble code (DTC). Some of these codes cause the transmission
to go into 9Limp-In9 or 9default9 mode. Some DTCs cause permanent Limp-In and others cause temporary Limp-In.
The NAG1 defaults in the current gear position if a DTC is detected, then after a key cycle the transmission will go
into Limp-in, which is mechanical 2nd gear. Some DTCs may allow the transmission to resume normal operation
(recover) if the detected problem goes away. A permanent Limp-In DTC will recover when the key is cycled, but if
the same DTC is detected for three key cycles the system will not recover and the DTC must be cleared from the
TCM with the appropriate scan tool.
NOTE: If the TCM has been replaced, the “TCM Adaptation Procedure” must be performed. (Refer to 8 -
ELECTRICAL/ELECTRONIC CONTROL MODULES/TRANSMISSION CONTROL MODULE - STANDARD PRO-
CEDURE)
TCM SIGNALS
The TCM registers one part of the input signals by direct inputs, the other part by CAN bus. In addition to the direct
control of the actuators, the TCM sends various output signals by CAN bus to other control modules.
Selector Lever Position
A series of sensors in the SLA inform the TCM of the position of the selector lever.
The TCM monitors the SLA for all shift lever positions through five position circuits. The SLA provides a low-current
12-volt signal to the TCM. The TCM compares the on/off signals to programmed combinations to determine the
exact position of the shift lever.
ATF Temperature Sensor
The ATF temperature sensor is a positive temperature co-efficient (PTC) thermistor. It measures the temperature of
the transmission fluid and is a direct input signal for the TCM. The temperature of the ATF has an influence on the
shifttime and resulting shift quality. As the temperature rises, resistance rises, and therefore, the probing voltage is
decreasing. Because of its registration, the shifting process can be optimized in all temperature ranges.
The ATF temperature sensor is wired in series with the park/neutral contact. The temperature signal is transmitted
to the TCM only when the reed contact of the park/neutral contact is closed because the TCM only reads ATF
temperature while in any forward gear, or REVERSE. When the transmission is in PARK or NEUTRAL, the TCM will
substitute the engine temperature for the ATF temperature.
Starter Interlock
The TCM monitors a contact switch wired in series with the transmission temperature sensor to determine PARK
and NEUTRAL positions. The contact switch is open in PARK and NEUTRAL. The TCM senses transmission tem-
perature as high (switch supply voltage), confirming switch status as open. The TCM then broadcasts a message
over CAN bus to confirm switch status. The PCM receives this information and allows operation of the starter circuit.
N2 and N3 Speed Sensors
The N2 and N3 Input Speed Sensors are two Hall-effect speed sensors that are mounted internally in the trans-
mission and are used by the TCM to calculate the transmission’s input speed. Since the input speed cannot be
measured directly, two of the drive elements are measured. Two input speed sensors were required because both
drive elements are not active in all gears.
CAN Bus Indirect Input Signals
A 2.5-volt bias (operating voltage) is present on the CAN bus any time the ignition switch is in the RUN position.
Both the TCM and the ABS apply this bias. On this vehicle, the CAN bus is used for module data exchange only.
The indirect inputs used on the NAG1 electronic control system are:
• Wheel Speed Sensors.
• Transfer Case Switch Status.
• Brake Switch.
• Engine RPM.
• Engine Temperature.
• Cruise Control Status.
• Gear Limit Request.
• Throttle Position - 0% at idle, 100% at WOT. If open, TCM assumes idle (0% throttle opening).
• Odometer Mileage
• Maximum Effective Torque.
• Engine in Limp-In Mode/Mileage Where DTC Was Set.
BRAKE TRANSMISSION SHIFT INTERLOCK (BTSI)

The BTSI solenoid prevents shifting out of the PARK position until the ignition key is in the RUN position and the
brake pedal is pressed. The TCM controls the ground while the ignition switch supplies power to the BTSI solenoid.
The PCM monitors the brake switch and broadcasts brake switch status messages over the CAN C bus. If the park
brake is depressed and there is power (Run/Start) to SLA, the BTSI solenoid deactivates. The TCM monitors this for
the SLA because the SLA does not communicate on the CAN bus.
SHIFT SCHEDULES
The basic shift schedule includes up and downshifts for all five gears. The TCM adapts the shift program according
to driving style, accelerator pedal position and deviation of vehicle speed. Influencing factors are:
• Road Conditions.
• Incline, Decline and Altitude.
• Trailer Operation, Loading.
• Engine Coolant Temperature.
• Cruise Control Operation.
• Sporty Driving Style.
• Low and High ATF Temperature.
Upshift To: 1-2 2-3 3-4 4-5

Activated By 1-2/4-5 2-3 3-4 1-2/4-5
Solenoid:
Shift Point (at 29 km/h (18 mph) 48 km/h (30 mph) 68 km/h (42 mph) 85 km/h (53 mph)
35.2% of throttle)
Downshift From: 5-4 4-3 3-2 2-1

Activated By 1-2/4-5 3-4 2-3 1-2/4-5
Solenoid:
Shift Point 55.7 km/h (34.61 40.5 km/h (25.17 24.4 km/h (15.16 15.1 km/h (9.38
mph) mph) mph) mph)
DOWNSHIFT SAFETY
Selector lever downshifts are not performed if inadmissible high engine rpm is sensed.
ADAPTATION
To equalize tolerances and wear, an automatic adaptation takes place for:
• Shift Time.
• Clutch Filling Time.
• Clutch Filling Pressure.
• Torque Converter Lock-Up Control.
Adaptation data may be stored permanently and to some extent, can be diagnosed.
Driving Style Adaptation
The shift point is modified in steps based on the information from the inputs. The control module looks at inputs
such as:
• vehicle acceleration and deceleration (calculated by the TCM).
• rate of change as well as the position of the throttle pedal (fuel injection information from the PCM).
• lateral acceleration (calculated by the TCM).
• gear change frequency (how often the shift occurs).
Based on how aggressive the driver is, the TCM moves up the shift so that the present gear is held a little longer
before the next upshift. If the driving style is still aggressive, the shift point is modified up to ten steps. If the driving
returns to normal, then the shift point modification also returns to the base position.
This adaptation has no memory. The adaptation to driving style is nothing more than a shift point modification meant
to assist an aggressive driver. The shift points are adjusted for the moment and return to base position as soon as
the inputs are controlled in a more normal manner.
CONTROLLER MODES OF OPERATION

Permanent Limp-In Mode
When the TCM determines there is a non-recoverable condition present that does not allow proper transmission
operation, it places the transmission in permanent Limp-In Mode. When the condition occurs the TCM turns off all
solenoids as well as the solenoid supply output circuit. If this occurs while the vehicle is moving, the transmission
remains in the current gear position until the ignition is turned off or the shifter is placed in the 9P9 position. When
the shifter has been placed in 9P,9 the transmission only allows 2nd gear operation. If this occurs while the vehicle
is not moving, the transmission only allows operation in 2nd gear.
Temporary Limp-In Mode
This mode is the same as the permanent Limp-In Mode except if the condition is no longer present, the system
resumes normal operation.
Under Voltage Limp-In Mode
When the TCM detects that system voltage has dropped below 8.5 volts, it disables voltage-dependant diagnostics
and places the transmission in the temporary Limp-In Mode. When the TCM senses that the voltage has risen
above 9.0 volts, normal transmission operation is resumed.
Hardware Error Mode
When the TCM detects a major internal error, the transmission is placed in the permanent Limp-In Mode and
ceases all communication over the CAN bus. When the TCM has entered this mode normal transmission operation
does not resume until all DTCs are cleared from the TCM.
Loss of Drive
If the TCM detects a situation that has resulted or may result in a catastrophic engine or transmission problem, the
transmission is placed in the neutral position. Improper Ratio, Input Sensor Overspeed or Engine Overspeed DTCs
cause the loss of drive.
Controlled Limp-in Mode
When a failure does not require the TCM to shut down the solenoid supply, but the failure is severe enough that the
TCM places the transmission into a predefined gear, there are several shift performance concerns. For instance, if
the transmission is slipping, the controller tries to place the transmission into 3rd gear and maintain 3rd gear for all
forward drive conditions.
STANDARD PROCEDURE
TCM QUICK LEARN - 42RLE Only
The quick learn procedure requires the use of the appropriate scan tool.
This program allows the electronic transmission system to recalibrate itself. This will provide the proper transmission
operation. The quick learn procedure should be performed if any of the following procedures are performed:
• Solenoid Pack Replacement
• Valve Body Replacement or Recondition
To perform the Quick Learn Procedure, the following conditions must be met:
• The brakes must be applied
• The engine speed must be above 500 rpm
• The throttle angle (TPS) must be less than 3 degrees
• The shift lever position must stay in PARK until prompted to shift to overdrive
• The shift lever position must stay in overdrive after the Shift to Overdrive prompt until the scan tool indicates
the procedure is complete.
• The calculated oil temperature must be above 60° and below 200°
TCM ADAPTATION - NAG1 Only

The adaptation procedure requires the use of the appropriate scan tool. This program allows the electronic trans-
mission system to re-calibrate itself. This will provide the proper baseline transmission operation. The adaptation
procedure should be performed if any of the following procedures are performed:
• Electrohydraulic Unit Replacement or Recondition
1. With the scan tool, reset the Transmission adaptives. Resetting the adaptives will set the adaptives to factory
settings.
NOTE: Perform the Coast Down Adaptations first. The Transmission Temperature must be greater than 60°C
(140°F) and less than 70°C (158°F). Failure to stay within these temperature ranges will void the procedure.
2. Drive the vehicle until the transmission temperature is in the specified range.
3. Perform 4 to 5 coast downs from 5th to 4th gear and then 4th to 3rd gear.
NOTE: For Upshift adaptation, the Transmission temperature must be greater than 60°C (140°F) and less
than 100°C (212°F). Failure to stay within these temperature ranges will void this procedure.
4. From a stop, moderately accelerate the vehicle and obtain all forward gear ranges while keeping the Engine
RPM below 1800 RPM. Repeat this procedure 4 to 5 times.
5. Obtaining 5th gear may be difficult at 1800 RPM. Allow the transmission to shift into 5th gear at a higher RPM
then lower the RPM to 1800 and perform manual shifts between 4th and 5th gears using the shift lever.
6. The TCM will store the adaptives every 10 minutes. After completion of the adaptation procedure make sure the
vehicle stays running for at least 10 minutes.
7. It is possible to manually store the adaptives under the 10 minute time frame using the scan tool Store Adaptives
procedure.

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LX ELECTRONIC CONTROL MODULES 8E - 1

ELECTRONIC CONTROL MODULES

ELECTRONIC CONTROL MODULES - ELECTRONIC CONTROL MODULES - SERVICE

ELECTRONIC CONTROL MODULES - ELECTRICAL

ELECTRONIC CONTROL MODULES - U0159-LOST COMMUNICATION WITH PARK

U0209-LOST COMMUNICATION WITH *NO RESPONSE FROM HSM (HEATED

ELECTRONIC CONTROL MODULES - ELECTRICAL DIAGNOSTICS

B210D-BATTERY VOLTAGE LOW

RESISTANCE IN THE BATTERY POSITIVE CIRCUIT

1. CHECK FOR ANY POWERTRAIN CONTROL MODULES DTCS

B210E-BATTERY VOLTAGE HIGH

(K20) GENERATOR FIELD CONTROL CIRCUIT SHORTED TO BATTERY VOLTAGE

1. CHECK FOR ANY POWERTRAIN CONTROL MODULES DTCS

B2112-5 VOLT SUPPLY CIRCUIT LOW

For a complete wiring diagram Refer to Section 8W.

(F891) 5 VOLT SUPPLY CIRCUIT SHORTED TO GROUND

1. CHECK FOR ACTIVE DTC

2. A/C PRESSURE TRANSDUCER

3. (F891) 5 VOLT SUPPLY CIRCUIT SHORTED TO GROUND

B2113-5 VOLT SUPPLY CIRCUIT HIGH

For a complete wiring diagram Refer to Section 8W.

(F891) 5 VOLT SUPPLY CIRCUIT SHORTED TO VOLTAGE

1. CHECK FOR ACTIVE DTC

2. A/C PRESSURE TRANSDUCER

3. (F891) 5 VOLT SUPPLY CIRCUIT SHORTED TO VOLTAGE

B2206-CURRENT VIN MISSING/MISMATCH

1. CHECK FOR ACTIVE DTC

2. CHECK VIN IN PCM

B2215-FRONT CONTROL MODULE INTERNAL

1. REPLACE THE FRONT CONTROL MODULE IF DTC IS ACTIVE

B222C-VEHICLE CONFIGURATION NOT PROGRAMMED

1. CHECK FOR ACTIVE DTC

2. CONFIGURE THE FCM TO THE VEHICLE

For a complete wiring diagram Refer to Section 8W.

(D65) CAN C BUS (+) CIRCUIT SHORTED TO GROUND

1. TEST FOR INTERMITTENT CONDITION

2. ANTILOCK BRAKE MODULE — INTERNAL SHORT

3. POWERTRAIN CONTROL MODULE — INTERNAL SHORT

4. SHIFTER LEVER ASSEMBLY (NAG1 ONLY)— INTERNAL SHORT

5. ELECTRONIC SHIFT MODULE (COLUMN NAG1)— INTERNAL SHORT

6. TRANSMISSION CONTROL MODULE (NAG1 ONLY)— INTERNAL SHORT

7. ENGINE CONTROL MODULE (DIESEL)— INTERNAL SHORT

8. STEERING CONTROL MODULE — INTERNAL SHORT

9. (D65) CAN C BUS (+) CIRCUIT SHORTED TO VOLTAGE

10. (D64) CAN C BUS (-) CIRCUIT SHORTED TO VOLTAGE

11. (D65) CAN C BUS (+) CIRCUIT SHORTED TO GROUND

12. (D64) CAN C BUS (-) CIRCUIT SHORTED TO GROUND

For a complete wiring diagram Refer to Section 8W.

(D55) CAN B BUS (+) CIRCUIT OPEN

1. TEST FOR INTERMITTENT CONDITION

2. MEASURE VOLTAGE AT FCM

3. (D55) CAN B BUS (+) CIRCUIT OPEN

4. (D54) CAN B BUS (-) CIRCUIT OPEN

5. (D55) CAN B BUS (+) CIRCUIT FOR A SHORT TO VOLTAGE

6. (D54) CAN B BUS (-) CIRCUIT FOR A SHORT TO VOLTAGE

7. (D55) CAN B BUS (+) CIRCUIT FOR A SHORT TO GROUND

8. (D54) CAN B BUS (-) CIRCUIT FOR A SHORT TO GROUND

U0100-LOST COMMUNICATION WITH ECM/PCM