Exterior Courtesy Lamps Malfunction

Exterior Courtesy Lamps Malfunction

Diagnostic Instructions

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

Circuit/System Description

The exterior courtesy lamps are supplied with the courtesy lamp supply voltage from the driver and passenger door lock and side window switches. The lamps are controlled by the driver and passenger door lock and side window switches through low side drive control circuits.

Circuit/System Verification

Ignition ON, command the Puddle/Courtesy Lamp ON and OFF with a scan tool. Verify the exterior courtesy lamps turn on and off.

Circuit/System Testing

1. Disconnect the harness connector at the affected courtesy lamp bulb.
2. Ignition ON, verify that a test lamp illuminates between the courtesy lamp supply circuit terminal and ground.

^ If the test lamp does not illuminate, test the courtesy lamp supply circuit for a short to ground or an open/high resistance.

3. Connect a test lamp between the low side control circuit terminal and the courtesy lamp supply circuit terminal.
4. Command the Puddle/Courtesy Lamp 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 ground. If the circuit tests normal, replace the door lock and side window switch.

^ If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the door lock and side window switch.

5. If all circuits test normal, test or replace the affected bulb.

Repair Instructions

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

* Outside Rearview Mirror Courtesy Lamp Replacement