Test Description

WARNING: This page is about a different car, the 2002 Buick Regal and 2002 Buick Century. However, it is still accessible from the selected car via links, so may be relevant.

The numbers below refer to the step numbers on the diagnostic table.

2. Listen for an audible click when the RAP relay operates. Command both the ON and OFF states. Repeat the command as necessary.
3. This step verifies that the Body Control Module (BCM) is providing ground to the RAP relay.

Fig 1: Identifying DTC B1478 Diagnostic Table

Courtesy of GENERAL MOTORS CORP.

Fig 2: Identifying DTC B1478 Diagnostic Table

Courtesy of GENERAL MOTORS CORP.