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Trunk Ajar Indicator Malfunction



Trunk Ajar Indicator Malfunction

Diagnostic Instructions

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

Diagnostic Fault Information





Circuit/System Description

The body control module (BCM) uses the rear compartment lid latch to determine the position of the trunk lid. When the lid is open, the rear compartment lid ajar switch is closed, providing a ground path for the trunk ajar switch signal circuit. When the BCM detects the trunk lid is ajar, a serial data message is sent to the driver information center (DIC) requesting the Trunk Ajar message be displayed.

Reference Information
Schematic Reference

Release Systems Schematics (Release Systems Diagrams)
Connector End View Reference

Component Connector End Views (Connector Views)
Electrical Information Reference

* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)

Scan Tool Reference

Control Module References (Programming and Relearning) for scan tool information

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the rear compartment lid latch.
2. Ignition ON, verify the Trunk Ajar message on the DIC is not displayed.

If the Trunk Ajar message is displayed, test the signal circuit terminal 2 for a short to ground. If the circuit tests normal, replace the BCM.

3. Install a 3-amp fused jumper between the signal circuit terminal 2 and ground. Verify the Trunk Ajar message is displayed on the DIC.

If the Trunk Ajar message is not displayed, test the signal circuit for a short to voltage or and open/high resistance. If the circuit tests normal, replace the BCM.

4. If all circuits test normal, test or replace the rear compartment lid latch.

Component Testing

1. Ignition OFF, disconnect the harness connector at the rear compartment lid latch.
2. Test for infinite resistance between the signal terminal 2 and the ground terminal 3 in the open position.

If not the specified value, replace the rear compartment lid latch.

3. Test for less than 2.0 ohms between the signal terminal 2 and the ground terminal 3 in the closed position.

If greater than the specified range, replace the rear compartment lid latch.

Repair Instructions

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

* Rear Compartment Lid Ajar Indicator Switch Replacement (Service and Repair)
* Control Module References (Programming and Relearning) for BCM replacement, setup and programming