Diagnostic Test

ACTIVE DTC 

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

   Is the DTC Active at this time?

   Yes 

   • Refer to the DIAGNOSTIC CODE INDEX and perform the U0121-Lost Communication with Anti-Lock Brake Module diagnostic procedure.

   No 

   • Refer to  DIAGNOSIS AND TESTING  and perform the Stored Lost Communication DTCs diagnostic procedure.