GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

Schematic Reference: Exterior Lights Schematics

Connector End View Reference: Master Electrical Component List

1

Did you perform the Lighting Systems Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Lighting Systems

2

  1. Turn ON the ignition.
  2. Shift the gear selector lever to the REVERSE position and then to the PARK position.

Do the backup lamps turn ON in the REVERSE position and turn OFF in the PARK position?

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

Go to Step 3

3

  1. Turn the ignition to ON position with the engine off.
  2. Install a scan tool, display the output controls-light test information.
  3. Display the backup light request information.

Does the scan tool indicate the Backup Light Request is OFF?

Go to Step 4

Go to Step 8

4

Disconnect the backup lamp (manual) switch or the park/neutral position (auto) switch connector.

Do the backup lamps turn OFF?

Go to Step 9

Go to Step 5

5

Remove the BACKUP relay #38 from the underhood electrical center.

Do the backup lamps turn OFF?

Go to Step 6

Go to Step 7

6

Test the backup lamp switch circuit for a short to battery positive voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 11

Go to Step 10

7

Repair a short to battery positive voltage in the backup lamp voltage supply circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 11

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8

Important: Perform the set-up procedure for the BCM. Refer to Body Control Module (BCM) Programming/RPO Configuration in Body Control System.

Replace the BCM. Refer to Body Control Module Replacement in Body Control System.

Did you complete the replacement?

Go to Step 11

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9

Replace the backup lamp (manual) switch or the park/neutral position (auto) switch. Refer to Backup Lamp Switch Replacement in Manual Transmission or Park/Neutral Position Switch Replacement in Automatic Transaxle.

Did you complete the replacement?

Go to Step 11

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10

Replace the BACKUP relay #38. Refer to Relay Replacement in Wiring Systems.

Did you complete the replacement?

Go to Step 11

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11

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2