GM Service Manual Online
For 1990-2009 cars only

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Action

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Schematic Reference: Interior Lights Schematics

Connector End View Reference: Master Electrical Component List in Wiring 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

  1. On the headlamp switch, turn the door switch to the ON position.
  2. Turn ON the instrument panel (I/P) dimmer switch or open one of the doors.

Do all of the courtesy lamps illuminate?

Go to Step 3

Go to Step 4

3

Open and close each door and the lift gate.

Do the courtesy lamps turn ON when you open each door and the lift gate?

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

Go to Step 5

4

Are all of the courtesy lamps inoperative?

Go to Step 7

Go to Step 12

5

Test the door open circuits for a high resistance, an open, or a short to battery positive voltage. 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 16

Go to Step 6

6

Test the ground circuit of the door latch assembly for a high resistance or an open. 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 16

Go to Step 11

7

  1. Disconnect the headlamp switch.
  2. Connect a jumper between the switched dome circuit and the ground circuit.

Do the dome lamps illuminate?

Go to Step 13

Go to Step 8

8

Inspect for an open or a short to battery positive voltage in the switched dome circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 16

Go to Step 9

9

Test for an open, short to ground or a short to battery positive voltage in the courtesy lamps control circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 16

Go to Step 10

10

Inspect for a poor connection at the harness connection of the body control module (BCM). 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 16

Go to Step 15

11

Inspect for a poor connection at the harness connection of the inoperative door latch assembly. 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 16

Go to Step 14

12

Repair the open in the inoperative courtesy lamp power supply voltage circuit or courtesy lamps control circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 16

--

13

Replace the headlamp switch. Refer to Headlamp Switch Replacement .

Did you complete the replacement?

Go to Step 16

--

14

Important: Perform the setup procedures for the BCM. Refer to Body Control Module (BCM) Programming/RPO Configuration in Computer/Integrating Systems.

Replace the inoperative door latch assembly. Refer to the following:

         in Doors
    •  Rear Door Lock Replacement in Doors
    •  Liftgate Latch Replacement in Body Rear End

Did you complete the replacement?

Go to Step 16

--

15

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 16

--

16

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 3