GM Service Manual Online
For 1990-2009 cars only

Test Description

The number(s) below refer to the step number(s) on the diagnostic table.

  1. The inability of the body control module (BCM) to enter the diagnostic mode may be due to a BCM malfunction.

  2. The symptoms list in Symptoms will determine the correct diagnostic procedure to use.

Step

Action

Yes

No

1

Is the vehicle equipped with content theft deterrent (UA6)?

Go to Step 2

Go to Symptoms - Horns

2

Attempt to enter the body control module (BCM) diagnostic mode. Refer to On-Board Diagnostic Features in Body Control System.

Does the BCM enter the diagnostic mode?

Go to Step 3

Go to Diagnostic System Check - Body Control System in Body Control System

3

Does the BCM display any DTCs?

Go to Step 4

Go to Symptoms - Horns

4

Does the BCM display DTC 7?

Go to Diagnostic Trouble Code (DTC) List

Go to Diagnostic Trouble Code (DTC) List in Body Control System