U1120

U1120-LOST WHEEL DISTANCE MESSAGE

For a complete wiring diagram, refer to the wiring information .

Theory of Operation

The Powertrain Control Module (PCM) receives the vehicle speed signal over the CAN C bus from the Anti-lock Brake Module.

- When Monitored:
Ignition on.

- Set Condition:
The Powertrain Control Module (PCM) either doesn't receive a bus message or receives an implausible bus message from the Anti-lock brake Module.





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, select View 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

- Follow the diagnostics for U0121-LOST COMMUNICATION WITH ABS MODULE. U0121.

No

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