Powertrain Control Module (PCM)

U0121-LOST COMMUNICATION WITH ABS

For a complete wiring diagram, refer to the Wiring Information.

- When Monitored:
With the ignition on.

Battery voltage between 10.0 and 17.0 volts.

Body Control Module (BCM) is configured correctly.

- Set Condition:
This module has not received an ABS Bus message over the CAN C circuit for approximately two to five seconds. The circuit is continuously monitored. If the vehicle is equipped with the stop/start feature, the system will be disabled when this DTC is active.





Diagnostic Test
ACTIVE DTC

NOTE: For vehicle communication problems, use the scan tool to refer to the Network Review Screen. The screen depicts a high level view of the vehicle network. Fault and problem areas appear in red. Selecting any of the network components allows access to the source of the problem.

1. Ignition on, engine not running.
2. With the scan tool, select view DTCs.

Is the DTC Active at this time?

Yes

- U0121-00 and perform the U0121-Lost Communication with Anti-Lock Brake Module diagnostic procedure.

No

- Manufacturer Code Charts and perform the Stored Lost Communication DTCs diagnostic procedure.