Document ID: 2789567

Diagnostic Instructions

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

Diagnostic Fault Information

Circuit	Short to Ground	Open/High Resistance	Short to Voltage	Signal Performance
Dome Lamp Control	B2615 02	2	2	—
Reading Lamp Control	1	1	1	—
Dome Lamp Defeat Signal	2	2	2	—
Dome/Reading Lamps Ground	—	1, 2	—	—
Dome/Reading Lamps - Rear Ground	—	1, 2	—	—
1. Courtesy Lamps Malfunction 2. Dome Lamps Malfunction

Circuit/System Description

When any door is opened, the door ajar switch contacts close and the body control module (BCM) receives a door-open input. The BCM illuminates the dome lamp when any door is opened or a door lock/unlock request is activated with the key fob. After all doors have been closed, the dome lamp will remain illuminated approximately 3 seconds after the last door closes. In the event that the dome lamp were to remain illuminated for more than 10 minutes with the ignition switch in the OFF position and no doors opened, the BCM will deactivate the dome lamp control circuit to prevent total battery discharge.

Reference Information

Schematic Reference

Interior Lights Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Interior Lighting Systems Description and Operation

Electrical Information Reference

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

Ignition ON.
Verify the scan tool Door Ajar Switch parameter changes between Active and Inactive while opening and closing each vehicle door.

If the parameter does not change
Refer to Door Ajar Indicator Malfunction.

If the parameter changes

Verify the scan tool Interior/Courtesy Lighting Master Switch parameter changes between Active and Inactive while turning the dome lamp defeat switch ON and OFF.

If the parameter does not change
Refer to Dome Lamp Switch Malfunction.

If the parameter changes

Verify the dome lamp turns ON and OFF while commanding the Courtesy Lamps Duty Cycle Command ON and OFF with a scan tool.

If the dome lamp does not turn ON and OFF
Refer to Dome Lamp Malfunction.

If the dome lamp turns ON and OFF

All OK.

Circuit/System Testing

Dome Lamp Switch Malfunction

Ignition OFF, scan tool disconnected, all doors closed, all accessories OFF, disconnect the harness connector at the E37A dome/reading lamps. It may take up to 2 minutes for all vehicle systems to power down.
Test for less than 10 Ω between the ground circuit terminal 6 and ground.

If 10 Ω or greater

Ignition OFF.
Test for less than 2 Ω in the ground circuit end to end.

If 2 Ω or greater, repair the open/high resistance in the circuit.
If less than 2 Ω, repair the open/high resistance in the ground connection.

If less than 10 Ω

Ignition ON.
Verify the scan tool Interior/Courtesy Lighting Master Switch parameter is Inactive.

If Active

Ignition OFF, disconnect the X1 harness connector at the K9 body control module.
Test for infinite resistance between the signal circuit terminal 4 and ground.

If less than infinite resistance, repair the short to ground on the circuit.
If infinite resistance, replace the K9 body control module.

If Inactive

Install a 3 A fused jumper wire between the signal circuit terminal 4 and the ground circuit terminal 6.
Verify the scan tool Interior/Courtesy Lighting Master Switch parameter is Active.

If not Active

Ignition OFF, disconnect the X1 harness connector at the K9 body control module, ignition ON.
Test for less than 1 V between the signal circuit and ground.

If 1 V or greater, repair the short to voltage on the circuit.

If less than 1 V

Test for less than 2 Ω in the signal circuit end to end.

If 2 Ω or greater, repair the open/high resistance in the circuit.
If less than 2 Ω, replace the K9 body control module.

If Active

Test or replace the E37A dome/reading lamps.

Dome Lamp Malfunction

Ignition OFF, all doors closed, all accessories OFF, disconnect the harness connector at the E37A dome/reading lamps. It may take up to 2 minutes for all vehicle systems to power down.
Test for less than 10 Ω between the ground circuit terminal 6 and ground.

If 10 Ω or greater

Ignition OFF.
Test for less than 2 Ω in the ground circuit end to end.

If 2 Ω or greater, repair the open/high resistance in the circuit.
If less than 2 Ω, repair the open/high resistance in the ground connection.

If less than 10 Ω

Connect a test lamp between the control circuit terminal 2 and ground.
Verify the test lamp turns ON and OFF when commanding the Courtesy Lamps Duty Cycle Command ON and OFF with a scan tool.

If the test lamp is always OFF

Ignition OFF, disconnect the X7 harness connector at the K9 body control module.
Test for infinite resistance between the control circuit and ground.

If less than infinite resistance, repair the short to ground on the circuit.

If infinite resistance

Test for less than 2 Ω in the control circuit end to end.

If 2 Ω or greater, repair the open/high resistance in the circuit.
If less than 2 Ω, replace the K9 body control module.

If the test lamp is always ON

Ignition OFF, disconnect the X7 harness connector at the K9 body control module, ignition ON.
Test for less than 1 V between the control circuit terminal and ground.

If 1 V or greater, repair the short to voltage on the circuit.
If less than 1 V, replace the K9 body control module.

If the test lamp turns ON and OFF

Test or replace the inoperative E37A dome/reading lamps.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

Dome Lamp Bulb Replacement
Courtesy Lamp Replacement
Control Module References for BCM replacement, programming, and setup

Dome Lamp

Related components