GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

Schematic Reference: Interior Lights Schematics

1

Did you perform the Lighting Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Lighting Systems

2

Verify the fault is present.

Does the system operate normally?

Go to Testing for Electrical Intermittents in Wiring Systems

Go to Step 3

3

  1. Ensure the dome lamp override switch is in the OFF position.
  2. With the Scan Tool , read the dome override switch status.

Does the scan tool display the switch status as OFF?

Go to Step 5

Go to Step 4

4

  1. Disconnect the headlamp and panel dimmer switch.
  2. With the scan tool, read the dome override switch status.

Does the scan tool display the switch status as OFF?

Go to Step 12

Go to Step 9

5

  1. Open the driver's door.
  2. With the scan tool, read the driver door jamb switch status.

Does the scan tool display the switch status as Active?

Go to Step 8

Go to Step 6

6

  1. Disconnect the LH mini wedge (door jamb switch).
  2. Connect a fused jumper wire between the door jamb switch signal circuit and the ground circuit of the door jamb switch.
  3. With the scan tool, read the driver door jamb switch status.

Does the scan tool display the switch status as Active?

Go to Step 13

Go to Step 7

7

  1. Connect a fused jumper wire between the door jamb switch signal circuit and a good ground.
  2. With the scan tool, read the driver door jamb switch status.

Does the scan tool display the switch status as Active?

Go to Step 10

Go to Step 11

8

  1. Remove the courtesy lamp relay.
  2. Using J 35616 , connect a fused jumper wire between the courtesy lamp output circuit and the ground circuit at the courtesy lamp relay.
  3. Open the drivers door.

Do the courtesy lamps light?

Go to Step 14

Go to Step 16

9

Repair the short to ground in the interior lamp defeat switch output circuit. Refer to Wiring Repairs in Wiring Systems.

If no short is found, replace the BCM. Refer to Body Control Module Replacement in Body Control System.

Did you complete the replacement?

Go to Step 18

--

10

Repair the open in the ground circuit. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 18

--

11

Repair the open in the door latch switch signal circuit between the LH mini wedge and the body control module (BCM). Refer to Wiring Repairs in Wiring Systems.

If no open is found, replace the BCM. Refer to Body Control Module Replacement in Body Control System.

Did you complete the repair?

Go to Step 18

--

12

Replace the headlamp and panel dimmer switch. Refer to Headlamp Switch Replacement .

Is the repair complete?

Go to Step 18

--

13

Replace the LH mini wedge (door jamb switch). Refer to Front Side Door Lock Actuator Replacement in Doors.

Did you complete the replacement?

Go to Step 18

--

14

Replace the courtesy lamp relay. Did you complete the replacement?

Go to Step 18

--

15

Replace the inadvert power relay.

Did you complete the replacement?

Go to Step 18

--

16

  1. Reinstall the courtesy lamp relay.
  2. Remove the inadvert power relay.
  3. Using J 35616 , connect a fused jumper wire between the fused battery positive circuit and the inadvertent power relay output circuit at the relay socket.
  4. Open drivers door.

Do the courtesy lamps light?

Go to Step 15

Go to Step 17

17

Replace the body control module. Refer to Body Control Module Replacement in Body Control System.

Did you complete the replacement?

Go to Step 18

--

18

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 3