Chevrolet Trax: Courtesy lamps malfunction

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/System Description

The body control module (BCM) supplies battery voltage to the reading lamps and sunshade mirror lamps via the courtesy lamp control circuit. The front reading lamps are controlled by an individual switch that is activated by the operator when additional cabin lighting is required. In the event that the reading lamps or sunshade lamps 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 courtesy lamp control circuit to prevent total battery discharge.

Reference Information

Schematic Reference

• Interior Lights Schematics (Encore) , Interior Lights Schematics (Trax)
• Body Control System Schematics (Encore) , Body Control System Schematics (Trax)

Connector End View Reference

WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX - ENCORE WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX - TRAX

Description and Operation

Interior Lighting Systems Description and Operation

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Testing

1. Ignition OFF, all doors closed, all accessories OFF, disconnect the harness connector at the appropriate component listed below.

• E37A Dome/Reading Lamps
• E36AH Dome Lamp
• A3L Sunshade - Left
• A3R Sunshade - Right

2. Test for less than 15 ohms between the appropriate ground circuit terminal listed below and ground.

• E37A Dome/Reading Lamps - terminal 6
• E36AH Dome Lamp - terminal 2
• A3L Sunshade - Left terminal B
• A3R Sunshade - Right terminal B
• If 15 ohms or greater

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

• If 2 ohms or greater, repair the open/high resistance in the circuit.
• If less than 2 ohms, repair the open/high resistance in the ground connection.
• If less than 15 ohms

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

• E37A Dome/Reading Lamps - terminal 1
• E36AH Dome Lamp - terminal 4
• A3L Sunshade - Left terminal A
• A3R Sunshade - Right terminal A

4. Verify the test lamp turns ON and OFF when commanding the Inadvertent Load ON and OFF with a scan tool.

• If the test lamp is always OFF

1. Ignition OFF, disconnect the X7 harness connector at the K9 Body Control Module.
2. 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

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

• If 2 ohms or greater, repair the open/high resistance in the circuit.
• If less than 2 ohms, replace the K9 Body Control Module.
• If the test lamp is always ON

1. Ignition OFF, disconnect the X7 harness connector at the K9 Body Control Module, ignition ON.
2. 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

5. Test or replace the inoperative courtesy lamp.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• Dome Lamp Bulb Replacement
• Center Reading Lamp Replacement
• Center Reading Lamp Bulb Replacement
• Control Module References for BCM replacement, programming, and setup

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