Diagnostic Aids

If the DTC B2742 is a history DTC, the fault may be intermittent. Refer to TESTING FOR INTERMITTENT AND POOR CONNECTIONS .
An intermittent short to ground in the following locations may cause an intermittent malfunction to occur:
- The signal circuit of the fog lamp switch
- The fog lamp switch
- The BCM
Fig 1: DTC B2742 Diagnosis
Courtesy of GENERAL MOTORS CORP.