GM Service Manual Online
For 1990-2009 cars only

Diagnostic Aids

The radio is enabled/disabled by class 2 messages from the body control module (BCM). The BCM contains an audio delay power timer which allows the radio to operate for up to 10 minutes after the ignition is turned off. The radio is deactivated when one of the following occurs:

  1. The driver door is open.
  2. The 10 minutes timer has elapsed.
  3. Loss of state of health message from the BCM.

If class 2 communication between the radio, BCM and data link connector is functioning properly, and the door ajar switches are working properly, replace the BCM.

Step

Action

Yes

No

Schematic Reference: Radio/Audio System Schematics

1

Did you perform a Diagnostic System Check - Radio/Audio System?

Go to Step 2

Go to Diagnostic System Check - Radio/Audio System

2

Verify that the doors are closed and perform the following:

  1. Turn ON the ignition, engine OFF for 5 seconds.
  2. Turn OFF the ignition.

Does the radio turn off after 10 minutes or upon opening the driver door?

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

Go to Step 3

3

  1. Install a scan tool.
  2. Open driver door.
  3. With the scan tool, verify the Driver Door Ajar Switch input indicates Open.

Does the switch input indicate Open?

Go to Step 4

Go to Interior Lights Schematics in Wiring Systems

4

Important:: Perform the set up procedure for the control module after replacement if needed.

Replace the Body Control Module. Refer to Body Control Module Replacement .

Did you complete the replacement?

System OK

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