When the ignition is ON, the body control module (BCM) supplies battery positive voltage to the rear compartment lid ajar switch through the rear compartment lid ajar switch signal circuit. When the rear compartment lid is opened, the signal circuit is connected to ground through the rear compartment lid ajar switch ground circuit and the voltage is pulled low within the BCM. In response, the BCM sends a serial data message to the driver information center (DIC) in the instrument panel cluster (IPC) to illuminate the rear compartment lid ajar indicator.

Schematic Reference

Release Systems Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Door Ajar Indicator Description and Operation

Electrical Information Reference

Scan Tool Reference

Control Module References for scan tool information

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

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

3. Install a 3A fused jumper wire between the signal circuit terminal 2 and the ground circuit terminal 3. Verify the scan tool Trunk Ajar Switch parameter is Trunk Ajar.

⇒	If not the specified value, test the signal circuit for a short to voltage or an 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.

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 with the ajar switch in the open position.

⇒	If less than the specified value, replace the rear compartment lid latch.

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

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

4. Test for infinite resistance between each terminal 2 and 3 and the rear compartment lid latch housing/case.

⇒	If less than the specified value, replace the rear compartment lid latch.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.