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U0155-NO CLUSTER BUS MESSAGE
For a complete wiring diagramRefer to Section 8W.
When Monitored:
Ignition key on and battery voltage greater than 10.4 volts.
Set Condition:
No messages received from the MIC (Instrument Cluster) for more than 20 seconds. One Trip Fault. Three
good trips to turn off the MIL.
Possible Causes
BUS CIRCUIT OPEN OR SHORTED
INSTRUMENT CLUSTER
PCM
Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - DIAGNOSIS AND TESTING for diagnostic
procedures and for further possible causes.
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING).
Diagnostic Test
1.ACTIVE DTC
Ignition on, engine not running.
With the scan tool, erase DTCs.
Cycle the ignition key on and off several times.
With the scan tool, read DTCs.
Does the DTC reset?
Ye s>>
Go To 2
No>>
Refer to the INTERMITTENT CONDITIONSymptom (Diagnostic Procedure).
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
2.COMMUNICATE WITH CLUSTER
With the scan tool, attempt to communicate with the Instrument cluster.
Can communication be established with the Instrument Cluster?
Ye s>>
Go To 3
No>>
Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - DIAGNOSIS AND TESTING for diag-
nostic procedures and for further possible causes.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
3.INSTRUMENT CLUSTER OPERATION
Start the engine
Allow the engine to idle.
Is the correct engine speed display in the instrument cluster (Tach)?
Ye s>>
Replace and program the Powertrain Control Module per Service Information.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
No>>
Refer to the Instrument Category and perform the appropriate symptom.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
Page 402 of 5267
U0168-LOST COMMUNICATION WITH SKREEM
For a complete wiring diagramRefer to Section 8W.
Page 403 of 5267
When Monitored:
Ignition run time is greater than 1 second. Battery voltage between 9 and 16volts. Engine run time greater
than 3 seconds.
Set Condition:
The PCM doesn’t receive a SKREEM message over the CAN C circuit for 7 consecutive seconds. The circuit
is continuously monitored.
Possible Causes
CAN C BUS OPEN OR SHORTED CONDITION
SKREEM
TIPM
PCM
Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - DIAGNOSIS AND TESTING for diagnostic
procedures and for further possible causes.
Diagnostic Test
1.ACTIVE DTC
Ignition on, engine not running.
With a scan tool, read PCM DTCs.
Is the DTC active at this time?
Ye s>>
Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - DIAGNOSIS AND TESTING for diag-
nostic procedures and for further possible causes.
No>>
Refer to the INTERMITTENT CONDITION Diagnostic Procedure.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
Page 404 of 5267
U110C-NO FUEL LEVEL BUS MESSAGE RECEIVED
For a complete wiring diagramRefer to Section 8W.
Page 405 of 5267

When Monitored:
Ignition on.
Set Condition:
When the PCM does not receive a fuel level signal from the TIPM over the CAN C circuit. The circuit is con-
stantly monitored. One Trip fault.
Possible Causes
CAN C BUS CIRCUIT OPEN OR SHORTED
TOTALLY INTEGRATED POWER MODULE
PCM
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING) .
Theory of Operation
The fuel level signal is a direct input to the Cluster. The fuel level signalis sent to the TIPM over the CAN B bus
circuit. The NGC receives the fuel level signal from the TIPM over the CAN C bus circuit.
Diagnostic Test
1.ACTIVE DTC
Ignition on, engine not running.
With the scan tool read Powertrain DTCs.
Is the DTC active at this time?
Ye s>>
Go To 2
No>>
Refer to the INTERMITTENT CONDITION Diagnostic Procedure.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
2.U0141-LOST COMMUNICATION WITH FRONT CONTROL MODULE ALSO ACTIVE
With the scan tool read DTCs.
Is the U0141-LOST COMMUNICATION WITH FRONT CONTROL MODULE also set?
Ye s>>
Follow the diagnostics for U0141-LOST COMMUNICATION WITH FRONT CONTROL MODULE (TIPM)
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
No>>
Replace and program the Powertrain Control Module per Service Information.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
Page 406 of 5267
U110E-LOST AMBIENT TEMPERATURE MESSAGE
For a complete wiring diagramRefer to Section 8W.
Page 407 of 5267

When Monitored:
Ignition on.
Set Condition:
The PCM doesn’t receive the ambient temperature signal over the CAN C bus from the TIPM. The circuit is
continuously monitored. One Trip fault.
Possible Causes
CAN C BUS CIRCUIT OPEN OR SHORTED
TOTALLY INTEGRATED POWER MODULE
PCM
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING).
Theory of Operation
The ambient temperature sensor signal is a direct input to the TIPM. The TIPM sends the PCM the ambient tem-
perature signal over the CAN C bus.
Diagnostic Test
1.ACTIVE DTC
Ignition on, engine not running.
With the scan tool read Powertrain DTCs.
Is the DTC active at this time?
Ye s>>
Go To 2
No>>
Refer to the INTERMITTENT CONDITION Diagnostic Procedure.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
2.U0141-LOST COMMUNICATION WITH FRONT CONTROL MODULE (TIPM) ALSO ACTIVE
With the scan tool read DTCs.
Is the U0141-NO BUS MESSAGE RECEIVED FROM THE TIPM also set?
Ye s>>
Follow the diagnostics for U0141-LOST COMMUNICATION WITH FRONT CONTROL MODULE (TIPM)
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
No>>
Replace and program the Powertrain Control Module per Service Information.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
Page 408 of 5267
U1110-LOST VEHICLE SPEED MESSAGE
For a complete wiring diagramRefer to Section 8W.