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 Schematics)
Connector End View Reference

Component Connector End Views (Connector Views)
Description and Operation

Door Ajar Indicator Description and Operation (Description and Operation)
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 Verification

Ignition ON, observe the scan tool Trunk Open Switch parameter while opening and closing the trunk lid. The parameter should change between Open and Closed.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the rear compartment lid latch.
2. Ignition ON, verify the scan tool Trunk Open Switch parameter is Closed.

• If not the specified value, test the signal circuit terminal 2 for a short to ground. If the circuit tests normal, replace the BCM.

• If the scan tool parameter is Closed and the DIC message displays Trunk Ajar, replace the DIC.

3. Install a 3-amp fused jumper between the signal circuit terminal 2 and ground. Verify the scan tool Trunk Open Switch parameter is Open.

• If not the specified value, test the signal circuit for a short to voltage or and open/high resistance. If the circuit tests normal, replace the BCM.

• If the scan tool parameter is Open and the DIC message is not displayed, replace the DIC.

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 and DIC replacement, setup and programming