GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

Schematic Reference: Interior Lights Schematics

Connector End View Reference: Master Electrical Component List in Wiring Systems.

1

Did you perform the Lighting Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Lighting Systems

2

  1. Turn ON the ignition with the engine OFF.
  2. Turn the interior lamp switch to the ON and then to the OFF position.
  3. Turn the courtesy lamps ON and then OFF by opening and closing the driver door.

Do the courtesy lamps function properly?

Go to Step 3

Go to Courtesy Lamps Inoperative

3

  1. Disconnect the cargo lamp.
  2. Using a test lamp connected to ground, probe the interior lamps switched voltage supply circuit.
  3. Turn the interior lamp switch to the ON position.

Does the test lamp illuminate?

Go to Step 4

Go to Step 6

4

  1. Using a test lamp connected to battery positive voltage, probe the courtesy lamps low control circuit.
  2. Turn the interior lamp switch to the ON position.

Does the test lamp illuminate?

Go to Step 5

Go to Step 7

5

Inspect for a poor connections at the harness connector of the cargo lamp. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 9

Go to Step 8

6

Repair an open or high resistance in the interior lamps switched voltage supply circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 9

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7

Repair an open or high resistance in the courtesy lamps low control circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 9

--

8

Replace the cargo lamp. Refer to Cargo Lamp Replacement .

Did you complete the repair?

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