GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2001 🢒 Cavalier 🢒 Body and Accessories 🢒 Wiring Systems 🢒 Diagnostic System Check - Retained Accessory Power

Test Description

The numbers below refer to the step numbers 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. This step tests for valid system power moding in all ignition switch positions.

    3.

  3. 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 BCM.

Does the scan tool communicate with the BCM?

Go to Step 3

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

3

Important: The engine may start during the following step. Turn OFF the engine as soon as you have observed the Crank power mode.

  1. Access the Class 2 Power Mode parameter in the Diagnostic Circuit Check menu on the scan tool.
  2. Rotate the ignition switch through all positions while observing the Class 2 Power Mode parameter.

Does the Class 2 Power Mode parameter reading match the ignition switch position for all switch positions?

Go to Step 4

Go to Power Mode Mismatch in Body Control System

4

Select the BCM display function on the scan tool.

Does the scan tool display any DTCs?

Go to Step 5

Go to Symptoms - Retained Accessory Power

5

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 6

6

Does the scan tool display any of the following DTCs?

    • B1000
    • B1001
    • B1372
    • B1382
    • B2965

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

Go to Step 7

7

Select the PCM display function on the scan tool.

Does the scan tool display DTC P0562?

Go to DTC P0562 in Engine Electrical

Go to Symptoms - Retained Accessory Power