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For 1990-2009 cars only

Trunk Release Inoperative Coupe

Diagnostic Fault Information

Important: Always perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

Circuit/System Description

The body control module (BCM) grounds the trunk release control signal circuit based on trunk release switch signal 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 LATCH 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

Body Rear End Schematics

Connector End View Reference

Body Rear End Connector End Views

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Scan Tool Reference

    •  Scan Tool Data List
    •  Scan Tool Data Definitions
    •  Scan Tool Output Controls

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 reading should change between Active and Inactive.
  2. Observe the scan tool Exterior Rear Compartment Lid Release Switch parameter while pressing and releasing the exterior rear compartment lid release switch. The reading should change between Active and Inactive.
  3. Command the Trunk Release to release with the scan tool output control. The trunk should release.

Circuit/System Testing

Trunk Release Inoperative from Interior Switch

  1. Ignition ON, disconnect the interior rear compartment lid release switch connector.
  2. Verify that the rear compartment lid releases with a 3-amp fused jumper connected between the trunk release switch signal circuit and ground.
  3. If the rear compartment lid does not release, test for an open or high resistance in the trunk release switch signal circuit. If the circuit/connectors test normal, replace the BCM.
  4. Verify that the rear compartment lid releases with a 3-amp fused jumper connected between the trunk release switch signal circuit and the switch ground.
  5. If the rear compartment lid does not release, test for an open or high resistance in the rear compartment lid release switch ground circuit.
  6. Test or replace the interior rear compartment lid release switch.

Trunk Release Inoperative from Exterior Switch

  1. Ignition ON, disconnect the exterior rear compartment lid release switch connector.
  2. Verify that the rear compartment lid releases with a 3-amp fused jumper connected between the trunk release switch signal and a good ground.
  3. If the rear compartment lid does not release, test for an open or high resistance in the trunk release switch signal circuit. If the circuit/connections test normal, replace the remote control door lock receiver (RCDLR).
  4. Verify that the rear compartment lid releases with a 3-amp jumper connected between the truck release switch signal circuit and the switch ground.
  5. If the rear compartment lid does not release, test for an open or high resistance in the rear compartment lid release switch ground circuit.
  6. Test or replace the exterior rear compartment lid release switch.

Trunk Release Inoperative for All Switches

  1. Ignition ON, disconnect the rear compartment lid pull down actuator connector.
  2. Verify that a test lamp illuminates when connected between the battery supply voltage circuit of the rear compartment lid pull down actuator and ground.
  3. If the test lamp does not illuminate, repair the open or high resistance in the battery supply voltage circuit.
  4. Verify that a test lamp illuminates when connected between the battery supply voltage circuit and the ground circuit of the rear compartment lid pull down actuator.
  5. If the test lamp does not illuminate, repair the open or high resistance in the rear compartment lid pull down actuator ground circuit.
  6. Connect a test lamp between the battery voltage supply circuit and the trunk release control signal circuit.
  7. Verify that the test lamp illuminates when using a scan tool to activate the Trunk Release output control.
  8. If the test lamp does not illuminate, inspect for an open or high resistance in the trunk release control signal circuit. If the circuit/connections test normal, replace the BCM.
    If the test lamp remains illuminated at all times, inspect for a short to ground in the trunk release control signal circuit. If the circuit/connections test normal, replace the BCM.
  9. Test or replace the rear compartment lid pull down actuator.

Repair Instructions

Important: Always perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Rear Compartment Lid and Fuel Filler Door Release Switch Replacement
    •  Rear Compartment Lift Window Latch Replacement
    •  Control Module References for BCM and RCDLR replacement, setup, and programming.

Trunk Release Inoperative Convertible and Z06

Diagnostic Fault Information

Important: Always perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

Circuit/System Description

The body control module (BCM) grounds the trunk release relay control circuit based on trunk release switch signal from either the interior rear compartment lid release switch or the exterior rear compartment lid release switch. The rear compartment lid latch assembly is supplied battery voltage via the TRUNK RELEASE fuse through the TRUNK RELEASE relay. 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 ground the trunk release relay control circuit, which will switch the TRUNK RELEASE relay. With the relay contacts close, battery voltage is supplied to the rear compartment lid latch assembly, opening the rear compartment.

Diagnostic Aids

If the folding top is not fully extended and latched or fully retracted with the tonneau closed, rear compartment lid release functionality will be suspended. For folding top concerns, refer to Symptoms - Roof .

Reference Information

Schematic Reference

Body Rear End Schematics

Connector End View Reference

Body Rear End Connector End Views

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Scan Tool Reference

    •  Scan Tool Data List
    •  Scan Tool Data Definitions
    •  Scan Tool Output Controls

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 reading should change between Active and Inactive.
  2. Observe the scan tool Exterior Rear Compartment Lid Release Switch parameter while pressing and releasing the exterior rear compartment lid release switch. The reading should change between Active and Inactive.
  3. Command the Trunk Release to release with the scan tool output control. The trunk should release.

Circuit/System Testing

Trunk Release Inoperative from Interior Switch

  1. Ignition ON, disconnect the interior rear compartment lid release switch connector.
  2. Verify that the rear compartment lid releases with a 3-amp fused jumper connected between the trunk release switch signal circuit and ground.
  3. If the rear compartment lid does not release, test for an open or high resistance in the trunk release switch signal circuit. If the circuit/connectors test normal, replace the BCM.
  4. Verify that the rear compartment lid releases with a 3-amp fused jumper connected between the trunk release switch signal circuit and the switch ground.
  5. If the rear compartment lid does not release, test for an open or high resistance in the rear compartment lid release switch ground circuit.
  6. Test or replace the interior rear compartment lid release switch.

Trunk Release Inoperative from Exterior Switch

  1. Ignition ON, disconnect the exterior rear compartment lid release switch connector.
  2. Verify that the rear compartment lid releases with a 3-amp fused jumper connected between the trunk release switch signal and a good ground.
  3. If the rear compartment lid does not release, test for an open or high resistance in the trunk release switch signal circuit. If the circuit/connections test normal, replace the remote control door lock receiver (RCDLR).
  4. Verify that the rear compartment lid releases with a 3-amp jumper connected between the truck release switch signal circuit and the switch ground.
  5. If the rear compartment lid does not release, test for an open or high resistance in the rear compartment lid release switch ground circuit.
  6. Test or replace the exterior rear compartment lid release switch.

Trunk Release Inoperative for All Switches

  1. Ignition OFF, remove the trunk release relay.
  2. Ignition ON, verify that a test lamp illuminates on the coil side and switch side of the relay when connected between the trunk release relay supply voltage circuit and ground.
  3. If the test lamp does not illuminate, repair the circuit for a short to ground or an open/high resistance.
  4. Verify that the rear compartment lid releases with a 15-amp fused jumper connected between the trunk release relay supply voltage circuit and the rear compartment lid release control circuit.
  5. If the rear compartment does not release, test for an open or high resistance on the rear compartment lid release control circuit and the rear compartment lid release ground circuit. If the circuit/connections test normal, replace the rear compartment lid latch assembly.
  6. Connect a test lamp between the battery voltage supply circuit and the trunk release relay control circuit.
  7. Verify that the test lamp illuminates when using a scan tool to activate the Trunk Release output control.
  8. If the test lamp does not illuminate, inspect for an open or high resistance in the trunk release relay control circuit. If the circuit/connections test normal, replace the BCM.
    If the test lamp remains illuminated at all times, inspect for a short to ground in the trunk release relay control circuit. If the circuit/connections test normal, replace the BCM.
  9. Test or replace the trunk release relay.

Repair Instructions

Important: Always perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Rear Compartment Lid Latch Replacement
    •  Rear Compartment Lid and Fuel Filler Door Release Switch Replacement
    •  Control Module References for BCM and RCDLR replacement, setup, and programming.