GM Service Manual Online
For 1990-2009 cars only

Courtesy Lamps Inoperative From Door Jamb Switch

Step

Action

Yes

No

Schematic Reference: Interior Lights Schematics

DEFINITION: Courtesy lamps are inoperative from the door jamb switch or switches only.

1

Did you perform the Lighting System 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. Open and close all of the vehicle's doors.
  3. Observe the courtesy lamps.

Do the courtesy lamps illuminate when each door is opened?

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

Go to Step 3

3

Are the courtesy lamps inoperative from the driver's door?

Go to Step 5

Go to Step 4

4

Are the courtesy lamps inoperative from all of the passenger doors?

Go to Step 7

Go to Step 6

5

  1. Close all of the vehicle's doors, except the driver's.
  2. Disconnect the driver's door jamb switch.
  3. Connect a 3 amp fused jumper wire between the door jamb switch signal wire and a good ground.

Do the courtesy lamps illuminate?

Go to Step 8

Go to Step 9

6

  1. Close all of the vehicle's doors, except the inoperative door.
  2. Disconnect the inoperative door jamb switch.
  3. Connect a 3 amp fused jumper wire between the door jamb switch signal wire and a good ground.

Do the courtesy lamps illuminate?

Go to Step 8

Go to Step 9

7

Test the passenger door jamb switch signal circuit for an open or high resistance between the body control module (BCM) and splice 290. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 14

Go to Step 11

8

Test the ground circuit of the inoperative door jamb switch for an open or high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 14

Go to Step 10

9

Test the inoperative door jamb switch signal circuit for an open or high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 14

Go to Step 11

10

Inspect for poor connections at the harness connector of the inoperative door jamb switch. 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 14

Go to Step 12

11

Inspect for poor connections at the harness connector 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 14

Go to Step 13

12

Replace the inoperative door jamb switch. Refer to Door Jamb Switch Replacement in Doors.

Did you complete the replacement?

Go to Step 14

--

13

Important: Perform the set up procedure for the body control module.

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

Did you complete the replacement?

Go to Step 14

--

14

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 3

Courtesy Lamps Inoperative From Instrument Panel Dimmer Switch

Step

Action

Yes

No

Schematic Reference: Interior Lights Schematics

DEFINITION: Courtesy lamps are inoperative from the instrument panel dimmer switch only.

1

Did you perform the Lighting System Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Lighting Systems

2

  1. Close all of the vehicle's doors.
  2. Wait 20 seconds.
  3. Place the instrument panel dimmer switch in the DOME position.

Do the courtesy lamps illuminate?

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

Go to Step 3

3

  1. Disconnect the instrument panel dimmer switch.
  2. Connect a 10 amp fused jumper wire between the courtesy lamp low control circuit of the instrument panel dimmer switch and a good ground.

Do the courtesy lamps illuminate?

Go to Step 4

Go to Step 5

4

Inspect for poor connections at the harness connector of the instrument panel dimmer switch. 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 7

Go to Step 6

5

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

Did you complete the repair?

Go to Step 7

--

6

Replace the instrument panel dimmer switch. Refer to Instrument Panel Lamp Dimmer Switch Replacement .

Did you complete the replacement?

Go to Step 7

--

7

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 3