GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

2

Place the room lamp switch in the ON position.

Does the room lamp illuminate?

Go to Testing for Intermittent Conditions and Poor Connections

Go to Step 3

3

  1. Disconnect the room lamp assembly.
  2. Probe the courtesy lamp supply voltage circuit with a test lamp that is connected to a good ground.

Does the test lamp illuminate?

Go to Step 4

Go to Step 6

4

Connect the test lamp between the courtesy lamp supply voltage circuit and the courtesy lamp low control circuit.

Does the test lamp illuminate?

Go to Step 5

Go to Step 7

5

Inspect for poor connections at the harness connector of the room lamp assembly.

Did you find and correct the condition?

Go to Step 9

Go to Step 8

6

Repair an open, high resistance in the courtesy lamp supply voltage circuit.

Did you complete the repair?

Go to Step 9

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7

Repair an open or high resistance in the courtesy lamp low control circuit.

Did you complete the repair?

Go to Step 9

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8

Replace the room lamp assembly.

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