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Bob
Bob, Auto Tech
Category: Chevy
Satisfied Customers: 4087
Experience:  Plus 40 years GM, over 30 certified with Chevrolet, ASE certified Master Tech. (Expired, Retired)
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2004 avalanche - dome lights do not come on when door..manually

This answer was rated:

2004 avalanche - dome lights do not come on when door opens, lights still operate manually

Unfortunately, this system does not work much like the old ones, with just power and grounds through the door switches. The lamps are also controlled by the driver door module and the passenger door module and the body control module. Most of the testing for the system requires the use of a class 2 scanner to run function tests on the system. The system still relies on grounds to turn on, but the grounding is now done through the control modules. I'm sending the diagnostic procedure, just in case you have access to a class 2 scanner. Wondering if the truck might still be covered by warranty?

Courtesy Lamps Inoperative

Step

Action

Yes

No

Schematic Reference: Interior Lights Schematics or Body Control System Schematics in Body Control System

Connector End View Reference: Lighting Systems Connector End Views , Body Control System Connector End Views in Body Control System or Master Electrical Component List in Wiring Systems

1

Did you perform the Lighting Systems Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Lighting Systems

2

Verify that the courtesy/dome lamps are inoperative.

Do the courtesy/dome lamps operate normally?

Go to Testing for Intermittent and Poor Connections in Wiring Systems

Go to Step 3

3

Are all courtesy lamps inoperative?

Go to Step 5

Go to Step 4

4

Test the voltage supply and ground circuits of the inoperative lamp 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 16

Go to Step 14

5

Are the courtesy lamps inoperative from a specific switch only?

Go to Step 6

Go to Step 11

6

Inspect the following related body control module (BCM), driver door module (DDM), passenger door module (PDM) data parameters, and check for a ground signal on the liftgate ajar signal circuit of the BCM with the liftgate open. Refer to Scan Tool Data List and Scan Tool Data Definitions for typical values and definitions:

  • The courtesy lamp switch
  • The interior lamp defeat switch
  • The door ajar switches

Was a problem found?

Go to Step 7

Go to Step 10

7

Disconnect and test the switch of the affected input circuit for proper continuity in the open and closed positions. Refer to Testing for Continuity in Wiring Systems.

Is continuity correct in both positions?

Go to Step 8

Go to Step 9

8

Test the signal and ground circuits of the affected input circuit for the following conditions:

Did you find and correct the condition?

Go to Step 16

Go to Step 10

9

Inspect for poor connections at the harness connector of the affected switch. Refer to Testing for Intermittent and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 16

Go to Step 12

10

Inspect for poor connections at the harness connector of the module in the affected circuit. Refer to Testing for Intermittent and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 16

Go to Step 13

11

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

Did you find and correct the condition?

Go to Step 16

Go to Step 15

12

Replace the switch in the affected circuit.

Did you complete the replacement?

Go to Step 16

--

13

Important

Perform the setup procedure for the replacement module as applicable.

 

Replace the module in the affected circuit. Refer to the appropriate replacement procedure:

Did you complete the replacement?

Go to Step 16

--

14

Replace the inoperative bulb.

Did you complete the repair?

Go to Step 16

--

15

Important

Perform the setup procedure for the BCM.

 

Replace the BCM. Refer to Body Control Module Replacement in Body Control System.

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

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