GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

Schematic Reference: Exterior Lights Schematics

Connector End View Reference: Lighting Systems Connector End Views or Body Control System Connector End Views in Body Control System

1

Did you perform the Lighting Systems Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Lighting Systems

2

Verify that the backup lamps are inoperative.

Do the backup lamps operate normally?

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

Go to Step 3

3

Is only one backup lamp inoperative?

Go to Step 5

Go to Step 4

4

Use the scan tool to check if there are any codes set in the current or history Powertrain DTC Information.

Are any codes present?

Go to Diagnostic System Check - Automatic Transmission in Automatic Transmission - 4L60-E/4L65-E

Go to Step 6

5

Test the backup lamp supply voltage and ground circuit for an open or high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct a condition?

Go to Step 9

Go to Step 7

6

Inspect for poor connections at the harness connector of the body control module (BCM). Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 9

Go to Step 8

7

Replace the affected backup lamp bulb. Refer to Backup Lamp Bulb Replacement .

Did you complete the replacement?

Go to Step 9

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8

Important: Perform the setup procedure for the BCM.

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

Did you complete the replacement?

Go to Step 9

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9

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 3