Courtesy Lamps Malfunction
Courtesy Lamps Malfunction
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (Diagnostic System Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Strategy Based Diagnosis) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Diagnostic Procedure Instructions) provides an overview of each diagnostic category.
Diagnostic Fault Information
Circuit/System Description
The body control module (BCM) applies battery voltage to the courtesy lamps through the courtesy lamps control circuit. When any door is opened, the door ajar switch contacts close and the BCM receives a door-open input. If the BCM receives a door lock or unlock input or a rear hatch open input, the BCM will activate the courtesy lamps control circuit, providing battery voltage to all of the dome lamps and reading lamps. The dome lamp switch consists of 3 positions, ON, DOOR, and OFF. When the dome lamp switch is placed in the DOOR position, the dome lamps will illuminate when a door is opened. The dome lamps are provided with battery voltage via the courtesy lamps control circuit and ground through the courtesy lamps low control circuit. In the event that any of these lamps were to remain illuminated for more than 20 minutes with the ignition switch in the OFF position, the BCM will deactivate the courtesy lamp high control circuit to prevent a total battery discharge condition.
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 (Circuit Testing)
* Connector Repairs (Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (Wiring Repairs)
Scan Tool Reference
Control Module References (Programming and Relearning) for scan tool information
Circuit/System Verification
1. Ignition ON, observe the scan tool Driver Door Ajar Sw. parameter while opening and closing the driver door. The reading should change between Door Ajar and Door Closed.
• If the Driver Door Ajar Sw. parameter does not change between Door Ajar and Door Closed, refer to Door Open Switch Malfunction.
2. Observe the scan tool Door Ajar Sw. parameter while opening and closing the front passenger door, left rear passenger door and right rear passenger door. The reading should change between Door Ajar and Door Closed.
• If the Door Ajar Sw. parameter does not change between Door Ajar and Door Closed, refer to Door Open Switch 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 when commanded, refer to Courtesy Lamp Malfunction.
4. Command the Inadvertent Power control 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 when commanded, refer to Courtesy Lamp Malfunction.
5. Turn the Rear Compartment Courtesy Lamp ON and OFF by opening and closing the trunk lid. The rear compartment courtesy lamp should turn ON and OFF when changing between the selected states.
• If the rear compartment courtesy lamp does not turn ON and OFF when selected, refer to Rear Compartment Courtesy Lamp Malfunction.
Circuit/System Testing
Door Open Switch Malfunction
1. Ignition OFF, disconnect the harness connector at the appropriate door jamb switch.
2. Ignition OFF and all vehicle systems OFF. It may take up to 2 minutes for all vehicle systems to power down. Test for less than 10 ohm between the low reference circuit terminal B and ground.
• If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the BCM.
3. Ignition ON, verify the appropriate scan tool Door Ajar Switch parameter is Door Ajar.
• If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the BCM.
4. Install a 3 A fused jumper wire between the signal circuit terminal A and the low reference circuit terminal B. Verify the appropriate scan tool Door Ajar Switch parameter is Door Closed.
• 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, replace the door jamb switch.
Courtesy Lamp Malfunction
1. Ignition OFF, disconnect the harness connector at the appropriate courtesy lamp.
2. Ignition OFF, scan tool OFF, doors CLOSED, interior lamps OFF, test for less than 5 ohm between the ground circuit listed below and ground.
* Dome lamp - terminal A
* Inside rearview mirror - terminal 8 (with UE1)
* Inside rearview mirror - terminal 2 (without UE1)
• 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.
* Dome lamp - terminal D
* Inside rearview mirror - terminal 6 (with UE1)
* Inside rearview mirror - terminal 7 (without UE1)
4. 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 OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.
• If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the BCM.
5. Connect a test lamp between B+ and the control circuit terminal listed below.
* Dome lamp - terminal B
* Inside rearview mirror low - terminal 1 (with UE1)
* Inside rearview mirror low - terminal 6 (without UE1)
6. Command the Inadvertent Power 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 OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the BCM.
• If the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the BCM.
7. If all circuits test normal, replace the courtesy lamp.
Rear Compartment Courtesy Lamp Malfunction
1. Ignition OFF, disconnect the harness connector at the rear compartment courtesy lamp.
2. Ignition OFF, trunk OPEN, verify that a test lamp illuminates between B+ and the control circuit terminal A.
• If the test lamp does not illuminate, test the control circuit for a short to voltage or an open/high resistance.
3. Ignition OFF, trunk OPEN, verify that a test lamp illuminates between the control circuit terminal B and ground.
• If the test lamp does not illuminate, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.
4. If all circuits test normal, replace the rear compartment courtesy lamp.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
* Front Side Door Jamb Switch Replacement (Front Side Door Jamb Switch Replacement)
* Rear Door Jamb Switch Replacement (Rear Door Jamb Switch Replacement)
* Cargo Lamp Replacement (Service and Repair)
* Dome Lamp Replacement (Service and Repair)
* Inside Rearview Mirror Replacement (Inside Rearview Mirror Replacement)
* Reading Lamp Replacement (Service and Repair)
* Control Module References (Programming and Relearning) for BCM replacement, setup, and programming