Schematic Reference: Interior Lights Dimming Schematics

Connector End View Reference: 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

1. Turn ON the ignition, with the engine OFF.
2. Turn ON the park lamps.
3. Rotate the I/P dimmer switch from maximum to minimum.

Does the interior backlighting operate properly?

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

Go to Step 3

1. Turn OFF the ignition.
2. Install a scan tool.
3. Turn ON the ignition, with the engine OFF.
4. Turn ON the park lamps.
5. With a scan tool, observe the Interior Dim Pot parameter in the instrument panel module (IPM) Open/Short data list.
6. Slowly move the I/P dimmer switch while observing the interior dim pot parameter.

Does the scan tool interior dim pot parameter change with the I/P dimmer switch movement?

Go to Step 4

Go to Step 10

Rotate the I/P dimmer switch from maximum to minimum.

Do all of the backlighting lamps decrease intensity with the I/P dimmer switch movement?

Go to Step 9

Go to Step 5

1. Turn OFF the ignition.
2. Disconnect the component with non dimming backlighting lamp.
3. Connect a test lamp between the backlight lamps control circuit and the backlight lamps ground circuit.
4. Turn ON the ignition, with the engine OFF.
5. Slowly rotate the I/P dimmer switch from maximum to minimum while observing the interior dim pot parameter.

Does the test lamp dim with the I/P dimmer switch rotation?

Go to Step 7

Go to Step 6

Test the backlight lamps control circuit for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 15

Go to Step 8

Inspect for poor connections at the harness connector of the component with non dimming backlighting lamp. 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 15

Go to Step 11

Inspect for poor connections at the harness connector of the dash integration module (DIM) or at the harness connector of the door module that controls the backlighting of the component with the non dimming backlighting. 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 15

Go to Step 13

Inspect for poor connections at the harness connector of the DIM. 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 15

Go to Step 12

Inspect for poor connections at the harness connector of the of the I/P 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 15

Go to Step 14

Replace the component with the non dimming backlighting lamp.

Did you complete the replacement?

Go to Step 15

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Important:: Perform the setup procedure for the DIM after replacement.

Replace the DIM. Refer to Dash Integration Module Replacement in Body Control System.

Did you complete the replacement?

Go to Step 15

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Important:: Perform the setup procedure for the DIM after replacement.

Replace the controlling module. Refer to Dash Integration Module Replacement in Body Control System and Door Control Module Replacement in Doors.

Did you complete the replacement?

Go to Step 15

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Replace the I/P dimmer switch. Refer to Headlamp Switch Replacement .

Did you complete the replacement?

Go to Step 15

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Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2