GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

Schematic Reference: Interior Lights Schematics

Connector End View Reference: Lighting Systems Connector End Views or Computer/Integrating Systems Connector End Views in Computer/Integrating Systems

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

2

Verify that the courtesy lamps are inoperative.

Do the courtesy lamps operate normally?

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

Go to Step 3

3

Is only one lamp inoperative?

Go to Step 4

Go to Step 5

4

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

Did you find and correct the condition?

Go to Step 13

Go to Step 11

5

Inspect both door ajar switch input data parameters for the body control module (BCM). Refer to Scan Tool Data List and Scan Tool Data Definitions for typical values and definitions.

Was a problem found?

Go to Step 6

Go to Step 8

6

Disconnect and test the switch of the affected input circuit for proper continuity in the open and closed positions. Refer to Circuit Testing in Wiring Systems.

Is continuity present?

Go to Step 7

Go to Step 10

7

Test the signal and ground circuits of the affected input circuit for an open or high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 13

Go to Step 9

8

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

Did you find and correct the condition?

Go to Step 13

Go to Step 9

9

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

Did you find and correct the condition?

Go to Step 13

Go to Step 12

10

Replace the switch in the affected circuit. Refer to Door Latch Replacement in Doors.

Did you complete the replacement?

Go to Step 13

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11

Replace the inoperative bulb.

Did you complete the repair?

Go to Step 13

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12

Replace the BCM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.

Did you complete the replacement?

Go to Step 13

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13

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 3