Courtesy Lamps Malfunction

Courtesy Lamps Malfunction

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (Initial Inspection and Diagnostic Overview) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Initial Inspection and Diagnostic Overview) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Initial Inspection and Diagnostic Overview) provides an overview of each diagnostic category.

Circuit/System Description

When a courtesy lamp request is seen, ignition voltage is supplied to each of the courtesy lamps by the body control module (BCM) via the courtesy lamp supply voltage circuit. The courtesy lamp supply voltage circuit controls the following lamps:

* I/P Courtesy Lamp - Left and Right
* Dome/Reading Lamp - Left and Right
* Reading Lamps - Overhead Console

Reference Information
Schematic Reference

Interior Lights Schematics (Interior Lights Schematics)
Connector End View Reference

Component Connector End Views (Connector Views)
Description and Operation

Interior Lighting Systems Description and Operation (Interior Lighting Systems Description and Operation)
Electrical Information Reference

* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)

Scan Tool Reference

Control Module References (Programming and Relearning) for Scan Tool Information

Circuit/System Verification

Ignition ON, verify the door ajar indicator is illuminated when each of the vehicle doors are open.

1. Verify the door ajar indicator is illuminated when each of the vehicle doors are open.

• If opening any of the vehicle doors does not result in the door ajar indicator illuminating, refer to Symptoms - Vehicle Access (Symptoms - Vehicle Access).

2. Ignition ON, observe the scan tool Interior Light Switch parameter while cycling the dome lamp switch ON and OFF. The parameter should change between Off and On when changing between the commanded states.

• If the parameter does not cycle between the specified value, refer to Dome Lamp Switch Circuit Malfunction.

3. Command the Interior Lamps ON and OFF with a scan tool. The courtesy lamps should turn ON and OFF when changing between the commanded states.

• If the courtesy lamps do not turn ON and OFF, refer to Courtesy Lamp Circuit Malfunction.

4. With the driver door open, observe the courtesy lamps while cycling the dome lamp defeat switch ON and OFF. The courtesy lamps should turn ON and OFF when changing between the commanded states.

• If the courtesy lamps do not turn ON and OFF, refer to Dome Lamp Defeat Switch Circuit Malfunction.

Circuit/System Testing

Dome Lamp Switch Circuit Malfunction
1. Ignition OFF, disconnect the harness connector at the headlamp switch.
2. Test for less than 10 ohms between the ground circuit terminal 17 and ground.

• If greater than the specified range, test the ground circuit for an open/high resistance.

3. Ignition ON, verify the scan tool Interior Light Switch parameter is Off.

• If not the specified value, test the signal circuit terminal 2 for a short to ground. If the circuit tests normal, replace the BCM.

4. Install a 3A fused jumper wire between the signal circuit terminal 2 and ground. Verify the scan tool Interior Light Switch parameter is On.

• If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the BCM.

5. If all circuits test normal, test or replace the headlamp switch.

Courtesy Lamp Circuit Malfunction
1. Ignition OFF, disconnect the harness connector at the appropriate courtesy lamp.
2. Test for less than 10 ohms between the ground circuit terminal B and ground:

• If greater than the specified range, test the ground circuit for an open/high resistance.

3. Connect a test lamp between the control circuit terminal listed below and ground:

* I/P Courtesy Lamp - Terminal A
* Dome/Reading Lamp - Terminal C
* Reading Lamps - Terminal C

4. Ignition ON, command the Interior Lamps ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states.

• If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the BCM.
• If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.

5. If all circuits test normal, test or replace the appropriate courtesy lamp bulb.

Courtesy Lamp Circuit Malfunction
1. Driver door open, disconnect the harness connector at the headlamp switch. Verify the courtesy lamps are illuminated.

• If the courtesy lamps are not illuminated, test the signal circuit terminal 4 for a short to ground. If the circuit tests normal, replace the BCM.

2. Install a 3A jumper wire between the signal circuit terminal 4 and ground. Verify the courtesy lamps are not illuminated.

• If the courtesy lamps are illuminated, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the BCM.

3. If all circuits test normal, test or replace the headlamp switch.

Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.

* Headlamp Switch Replacement (Service and Repair)
* Door Courtesy Lamp and Reflector Replacement (Door Courtesy Lamp and Reflector Replacement)
* Instrument Panel Courtesy Lamp Bulb Replacement (Instrument Panel Courtesy Lamp Bulb Replacement)
* Overhead Console Courtesy Lamp Replacement (with Sunroof) (Overhead Console Courtesy Lamp Replacement (with Sunroof))Overhead Console Courtesy Lamp Replacement (without Sunroof) (Overhead Console Courtesy Lamp Replacement (without Sunroof))
* Control Module References (Programming and Relearning) for BCM replacement, setup, and programming