GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2000 🢒 Trans Sport (Export) 🢒 Body and Accessories 🢒 Retained Accessory Power 🢒 Diagnostic System Check - Retained Accessory Power

Test Description

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

  1. Lack of communication may be due to a partial malfunction of the class 2 serial data circuit or due to a total malfunction of the class 2 serial data circuit. The specified procedure will determine the particular condition.

    2.

  2. The presence of DTCs which begin with U indicate some other module is not communicating. The specified procedure will compile all the available information before tests are performed.

Step

Action

Yes

No

1

Install a scan tool.

Does the scan tool power up?

Go to Step 2

Go to Scan Tool Does Not Power Up in Data Link Communications

2

  1. Turn ON the ignition, with the engine OFF.
  2. Attempt to establish communication with the radio.

Does the scan tool communicate with the radio?

Go to Step 3

Go to Scan Tool Does Not Communicate with Class 2 Device in Data Link Communication

3

Does the scan tool display any DTCs which begin with a U?

Go to Scan Tool Does Not Communicate with Class 2 Device in Data Link Communications

Go to Step 4

4

Enter the BCM Diagnostic Mode. Refer to On-Board Diagnostic Features in Body Control Systems.

Does the BCM enter the Diagnostic Mode?

Go to Symptoms

Go to Body Control Module Inoperative