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U0121 - Lost Communication With Anti-Lock Brake System (Abs) Control Module A

DTC DESCRIPTION U0121 - LOST COMMUNICATION WITH ANTI-LOCK BRAKE SYSTEM (ABS) CONTROL MODULE A

Description:  The PCM continuously monitors the controller area network (CAN) for messages from the ABS. This DTC sets when the PCM fails to receive the ABS message within the defined amount of time.
Possible Causes: 
  • Communication error
Diagnostic Aids:  Check for other PCM DTCs or PCM related symptoms. Diagnose all other PCM DTCs or PCM related symptoms first.
Application  Key On Engine Off  Key On Engine Running  Continuous Memory 
All GO to Pinpoint Test QA.