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 Data Communication Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

2

Turn ON the underhood lamp.

Does the system operate normally?

Go to Testing for Intermittent Conditions and Poor Connections

Go to Step 3

3

Are all of the reading, visor, and the underhood lamp inoperative?

Go to Step 4

Go to Step 5

4

Test the inadvertent power supply voltage circuit of the body control module (BCM) for a high resistance or an open. Refer to Circuit Testing and Wiring Repairs.

Did you find and correct the condition?

Go to Step 12

Go to Step 8

5

Test the inadvertent power supply voltage circuit of the underhood lamp for a high resistance or an open. Refer to Circuit Testing and Wiring Repairs.

Did you find and correct the condition?

Go to Step 12

Go to Step 6

6

Test the ground circuit of the underhood lamp for high resistance or an open. Refer to Circuit Testing and Wiring Repairs.

Did you find and correct the condition?

Go to Step 12

Go to Step 7

7

Inspect the inoperative bulb for an open filament.

Is the bulb OK?

Go to Step 10

Go to Step 9

8

Inspect for poor connections at the harness connector of the BCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs.

Did you find and correct the condition?

Go to Step 12

Go to Step 11

9

Replace the inoperative bulb.

Did you complete the replacement?

Go to Step 12

--

10

Replace the underhood lamp. Refer to Underhood Lamp Replacement .

Did you complete the replacement?

Go to Step 12

--

11

Replace the BCM. Refer to Control Module References for replacement, setup, and programming.

Did you complete the replacement?

Go to Step 12

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12

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 3