Trunk Release Inoperative (Coupe)
Trunk Release Inoperative (Coupe)
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) grounds the trunk release control signal circuit based on trunk release switch signals from either the interior rear compartment lid release switch or the exterior rear compartment lid release switch. The rear compartment lid pull down actuator is supplied battery voltage at all times via the TRUNK RELEASE fuse. When either the interior or exterior rear compartment lid release switch is pressed, the trunk release switch signal circuit is grounded. This input will request the BCM to momentarily ground the trunk release control signal circuit, which will open the rear compartment lid.
Reference Information
Schematic Reference
Release Systems Schematics (Release Systems Schematics)
Connector End View Reference
Component Connector End Views (Connector Views)
Description and Operation
Luggage Compartment Description and Operation (Coupe) (Description and Operation)Luggage Compartment Description and Operation (Convertible and Z06) (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)
Circuit/System Testing
Trunk Release Inoperative from Interior Switch
1. Ignition OFF, disconnect the harness connector at the interior rear compartment lid release switch.
2. Ignition OFF, verify that a test lamp illuminates between B+ and the ground circuit terminal A.
• If the test lamp does not illuminate, test the ground circuit for an open/high resistance.
3. Ignition ON, verify the scan tool trunk release switch parameter is INACTIVE.
• If not the specified value, test the signal circuit terminal D for a short to ground. If the circuit tests normal, replace the BCM.
4. Install a 3-A fused jumper wire between the signal circuit terminal D and ground. Verify the scan tool Trunk Release Switch parameter is ACTIVE.
• 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.
5. If all circuits test normal, test or replace the interior rear compartment lid release switch.
Trunk Release Inoperative from Exterior Switch
1. Ignition OFF, disconnect the harness connector at the exterior rear compartment lid release switch.
2. Ignition OFF, exterior lamps OFF, test for less than 5.0 ohms of resistance between the ground circuit terminal A and ground.
• If greater than the specified range, test the ground circuit for an open/high resistance.
3. Ignition ON, verify the scan tool Exterior Rear Compartment Lid Release Switch parameter is INACTIVE.
• If not the specified value, test the signal circuit terminal B for a short to ground. If the circuit tests normal, replace the remote control door lock receiver (RCDLR).
4. Install a 3-A fused jumper wire between the signal circuit terminal B and ground. Verify the scan tool Exterior Rear Compartment Lid Release Switch parameter is ACTIVE.
• 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 remote control door lock receiver (RCDLR).
5. If all circuits test normal, test or replace the exterior rear compartment lid release switch.
Trunk Release Inoperative from Key Switch
1. Ignition OFF, disconnect the harness connector at the rear compartment lid pull down actuator.
2. Ignition OFF, exterior lamps OFF, test for less than 5.0 ohms of resistance between the ground circuit terminal F and ground.
• If greater than the specified range, test the ground circuit for an open/high resistance.
3. Ignition ON, verify the scan tool Trunk Key Cylinder Switch parameter is INACTIVE.
• If not the specified value, test the signal circuit terminal E for a short to ground. If the circuit tests normal, replace the BCM.
4. Install a 3-A fused jumper wire between the signal circuit terminal E and ground. Verify the scan tool trunk key cylinder switch parameter is ACTIVE.
• 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.
5. If all circuits test normal, test or replace the rear compartment lid pull down actuator.
Trunk Release Inoperative from All Switches
1. Ignition OFF, disconnect the harness connector at the rear compartment lid pull down actuator.
2. Ignition OFF, exterior lamps OFF, test for less than 5.0 ohms of resistance between the ground circuit terminal F and ground.
• If greater than the specified range, test the ground circuit for an open/high resistance.
3. Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal H and ground.
• If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance. If the circuit tests normal and the B+ circuit fuse is open, test or replace the rear compartment lid pull down actuator.
4. Connect a test lamp between the control circuit terminal B and the B+ circuit terminal H.
5. Command the trunk release 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 ground. If the circuit tests normal, replace the BCM.
• If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the BCM.
6. If all circuits test normal, test or replace the rear compartment lid pull down actuator.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
* Rear Compartment Lid Lock Cylinder Replacement (Service and Repair)
* Rear Compartment Lid Latch Replacement (Service and Repair)
* Rear Compartment Lid and Fuel Filler Door Release Switch Replacement (Service and Repair)
* Rear Compartment Lift Window Latch Replacement (Service and Repair)
* Control Module References (Programming and Relearning) for BCM and RCDLR replacement, setup, and programming