Trunk Release Inoperative (Coupe)
Trunk Release Inoperative (Coupe)
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provides an overview of each diagnostic category.
Diagnostic Fault Information
Circuit/System Description
The body control module (BCM) monitors the voltage on the trunk release signal circuit, when the interior rear compartment lid release switch is pressed, a contact within the switch closes. The BCM detects the drop in voltage in the trunk release signal circuit and provides a ground for the rear compartment lid pulldown actuator which releases the trunk lid. The remote control door lock receiver (RCDLR) monitors the voltage on it's trunk release signal circuit, when the exterior rear compartment lid release switch is pressed, a contact within the switch closes. The RCDLR detects the drop in voltage in the trunk release signal circuit and will send a serial data message to the BCM to command the rear compartment lid pulldown actuator.
Reference Information
Schematic Reference
Release Systems Schematics Release Systems Schematics
Connector End View Reference
Component Connector End Views Folding Top 5 Bow Lowered Switch (CM7)
Description and Operation
Luggage Compartment Description and Operation (Coupe) Luggage Compartment (Coupe)Luggage Compartment Description and Operation (Convertible and Z06) Luggage Compartment (Convertible and Z06)
Electrical Information Reference
* Circuit Testing Circuit Testing
* Connector Repairs Connector Repairs
* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections
* Wiring Repairs Wiring Repairs
Scan Tool Reference
Control Module References Control Module References for scan tool information
Circuit/System Verification
1. Ignition ON, observe the scan tool Trunk Release Switch parameter while pressing and releasing the interior rear compartment lid release switch. The parameter should change between Active and Inactive.
• If the parameter does not change, refer to Interior Trunk Release Switch Malfunction.
2. Observe the scan tool Ext. Rear Compartment Lid Release Sw. parameter while pressing and releasing the exterior rear compartment lid release switch. The parameter should change between Active and Inactive.
• If the parameter does not change, refer to Exterior Trunk Release Switch Malfunction.
3. Insert the key into the trunk lock cylinder and observe the scan tool Trunk Key Cylinder Switch parameter while turning the key to the OPEN position, the parameter should change between Inactive and Active.
• If the parameter does not change, refer to Trunk Key Switch Malfunction.
4. Command the Trunk Release with a scan tool, the rear compartment lid pulldown actuator should release the trunk lid.
• If the trunk lid does not release, refer to Trunk Release Malfunction.
Circuit/System Testing
Interior Trunk Release Switch Malfunction
1. Ignition OFF, disconnect the harness connector at the interior rear compartment lid release switch.
2. 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.
Exterior Trunk Release Switch Malfunction
1. Ignition OFF, disconnect the harness connector at the exterior rear compartment lid release switch.
2. Test for less than 5 ohms 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 Ext. Rear Compartment Lid Release Sw. 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 RCDLR.
4. Install a 3A fused jumper wire between the signal circuit terminal B and ground. Verify the scan tool Ext. Rear Compartment Lid Release Sw. 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 RCDLR.
5. If all circuits test normal, test or replace the exterior rear compartment lid release switch.
Trunk Key Switch Malfunction
1. Ignition OFF, disconnect the harness connector at the rear compartment lid pull down actuator.
2. 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.
3. Install a 3A 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.
4. If all circuits test normal, replace the rear compartment lid pull down actuator.
Trunk Release Malfunction
1. Ignition OFF, disconnect the harness connector at the rear compartment lid pull down actuator.
2. Test for less than 5 ohms 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.
Component Testing
Rear Compartment Lid Pull Down Actuator
1. Ignition OFF, disconnect the harness connector at the rear compartment lid pull down actuator.
2. Install a 15A fused jumper wire between the B+ terminal H and 12 volts. Install a jumper wire between the control terminal B and ground. Verify the rear compartment lid pull down actuator activates.
• If the rear compartment lid pull down actuator does not perform as specified, replace the rear compartment lid pull down actuator.
Rear Compartment Lid Release Switch
1. Ignition OFF, disconnect the harness connector at the appropriate rear compartment lid release switch.
2. Test for infinite resistance between the signal terminal and the ground terminal listed below with the switch in the open position.
* Interior rear compartment lid release switch signal terminal D and ground terminal A.
* Exterior rear compartment lid release switch signal terminal B and ground terminal A.
• If not the specified value, replace the rear compartment lid release switch.
3. Test for less than 2 ohms between the signal terminal and the ground terminal listed below with the switch in the closed position.
* Interior rear compartment lid release switch signal terminal D and ground terminal A.
* Exterior rear compartment lid release switch signal terminal B and ground terminal A.
• If greater than the specified range, replace the rear compartment lid release switch.
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 Rear Compartment Lid Latch Replacement
* Rear Compartment Lid and Fuel Filler Door Release Switch Replacement Service and Repair
* Rear Compartment Lift Window Latch Replacement Rear Compartment Lift Window Latch Replacement
* Control Module References Control Module References for BCM or RCDLR replacement, setup, and programming