Rear Compartment Lamp Malfunction

Rear Compartment Lamp 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 rear cargo courtesy lamp through the rear cargo lamp control circuit. When the BCM receives a rear liftgate open input from the rear liftgate latch, the BCM applies battery voltage to the rear cargo lamp control circuit illuminating the rear cargo courtesy lamp. In the event that the rear cargo 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 rear cargo lamp control circuit to prevent total battery discharge.

Reference Information
Schematic Reference

* Interior Lights Schematics Interior Lights Schematics
* Body Control System Schematics [1][2]Body Control Systems

Connector End View Reference

Component Connector End Views Hybrid/EV Battery Pack X1
Description and Operation

Interior Lighting Systems Description and Operation Interior Lighting Systems
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 Testing

1. Vehicle OFF, disconnect the harness connector at the E33 cargo lamp.
2. Vehicle OFF, exterior lamps OFF, test for less than 5 ohm between the ground circuit terminal 2 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 1 and ground.
4. Vehicle in Service Mode, command the Cargo 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 voltage. If the circuit tests normal, replace the K9 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 K9 BCM.

5. If all circuits test normal, replace the E33 cargo lamp.

Repair Instructions

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

* Rear Compartment Courtesy Lamp Replacement Rear Compartment Courtesy Lamp Replacement
* Control Module References Programming and Relearning for BCM replacement, setup, and programming