U1120

U1120-LOST WHEEL DISTANCE MESSAGE





For a complete wiring diagram Consult Diagrams/Electrical.

- When Monitored:
Ignition on.

- Set Condition:
The PCM doesn't receive a wheel distance message from the Anti-lock brake Module or FCM (NON-ABS) over the CAN C bus. One trip fault.





Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Initial Inspection and Diagnostic Overview.

Theory of Operation

The PCM receives the vehicle speed signal over the CAN C bus from the Anti-lock Brake Module or FCM (NON-ABS).

Diagnostic Test

1. ACTIVE DTC
Ignition on, engine not running.
With the scan tool, select View PCM DTCs.
Is the DTC Active at this time?

Yes

- Go To 2

No

- Refer to the INTERMITTENT CONDITION Diagnostic Procedure. Intermittent Condition.

2. U0121-LOST COMMUNICATION WITH ABS MODULE/P0141-LOST COMMUNICATION WITH FCM ALSO SET
NOTE: If the vehicle is not equipped with ABS the VSS signal will come from the FCM.

With the scan tool, read the appropriate module for DTCs.
Is the U0121-LOST COMMUNICATION WITH ABS MODULE/P0141-Lost Communicate With FCM also set?

Yes

- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

No

- Replace and program the Powertrain Control Module.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.