U1120
U1120-LOST WHEEL DISTANCE MESSAGE
For a complete wiring diagram, refer to the Wiring Information.
Theory of Operation
The PCM receives the vehicle speed signal over the CAN C bus from the Anti-lock Brake Module.
- When Monitored:
Ignition on.
- Set Condition:
The PCM doesn't receive a vehicle speed signal from the Anti-lock brake Module over the CAN C bus. One Trip fault.
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Pre-Diagnostic Troubleshooting Procedure.
1. ACTIVE DTC
1. Ignition on, engine not running.
2. With the scan tool, view PCM DTCs.
Is the DTC Active at this time?
Yes
- Go To 2
No
- Perform the INTERMITTENT CONDITION diagnostic procedure. Intermittent Condition Test.
2. U0121-LOST COMMUNICATION WITH ABS MODULE ALSO SET
1. With the scan tool continue reading DTCs.
Is the U0121-LOST COMMUNICATION WITH ABS MODULE also set?
Yes
- Perform the U0121-Lost Communication with ABS Module diagnostic procedure. U0121
No
- Replace and program the Powertrain Control Module.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test