Diagnostic Test

VERIFY THE DTC IS ACTIVE 

1. Turn the ignition on.
2. With the scan tool, read DTCs and record on vehicle work order.

   Is the DTC active at this time?

   Yes 

   • Refer to  DIAGNOSIS AND TESTING  and perform the U0121-00-Lost Communication with Anti-lock Brake System (ABS) Module diagnostic procedure.

   No 

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