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For 1990-2009 cars only

Trunk Release Inoperative Convertible

Diagnostic Instructions

    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    •  Diagnostic Procedure Instructions provides an overview of each diagnostic category.

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

Trunk Key Switch Signal

3

3

3

--

Trunk Release Relay Control

4

4

B3265

--

Trunk Release Switch Signal - Exterior

B3618

2

2

--

Trunk Release Switch Signal - Interior

1

1

1

--

Rear Compartment Lid Latch Assembly B+

4

4

4

--

Rear Compartment Lid Key Switch Ground

3

3

3

--

Rear Compartment Lid Latch Assembly Ground

4

4

4

--

Rear Compartment Lid Release Switch Exterior Ground

2

2

2

--

Rear Compartment Lid Release Switch Interior Ground

1

1

1

--

1. Trunk Release Inoperative from Interior Switch

2. Trunk Release Inoperative from Exterior Switch

3. Trunk Release Inoperative from Key Switch

4. Trunk Release Inoperative from All Switches

Circuit/System Description

The body control module (BCM) grounds the trunk release relay control 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 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 closed, battery voltage is supplied to the rear compartment lid latch assembly, opening the rear compartment. For more detailed information concerning trunk release operation refer to Luggage Compartment Description and Operation .

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

Release Systems Schematics

Connector End View Reference

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

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. Test for less than 1.0 ohm of resistance between the ground circuit terminal A and ground.
  3. If greater than the specified range, test the ground circuit for an open/high resistance.
  4. Ignition ON, verify the scan tool Trunk Release Switch parameter is INACTIVE.
  5. If not the specified value, test the signal circuit terminal D for a short to ground. If the circuit tests normal, replace the BCM.
  6. 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.
  7. 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.
  8. 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. Test for less than 1.0 ohm of resistance between the ground circuit terminal A and ground.
  3. If greater than the specified range, test the ground circuit for an open/high resistance.
  4. Ignition ON, verify the scan tool Exterior Rear Compartment Lid Release Switch parameter is INACTIVE.
  5. 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).
  6. 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.
  7. 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).
  8. 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 key switch.
  2. Test for less than 1.0 ohm of resistance between the ground circuit terminal 2 and ground.
  3. If greater than the specified range, test the ground circuit for an open/high resistance.
  4. Ignition ON, verify the scan tool Trunk Key Cylinder Switch parameter is INACTIVE.
  5. If not the specified value, test the signal circuit terminal 1 for a short to ground. If the circuit tests normal, replace the BCM.
  6. Install a 3-A fused jumper wire between the signal circuit terminal 1 and ground. Verify the scan tool Trunk Key Cylinder Switch parameter is ACTIVE.
  7. 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.
  8. If all circuits test normal, test or replace the rear compartment lid key switch.

Trunk Release Inoperative from All Switches

  1. Ignition OFF, disconnect the trunk release relay.
  2. Ignition ON, verify that a test lamp does not illuminate between the control circuit terminal D9 and ground.
  3. If the test lamp illuminates, test the control circuit for a short to voltage.
  4. Verify that a test lamp illuminates between the B+ circuit terminal C7 and ground.
  5. 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 the control circuit terminal D9 for a short to ground. If the circuit tests normal, test or replace the trunk release relay.
  6. Verify that a test lamp illuminates between the B+ circuit terminal D7 and ground.
  7. If the test lamp does not illuminate, test the B+ circuit for an open/high resistance.
  8. Disconnect the harness connector at the rear compartment lid latch assembly.
  9. Test for less than 1.0 ohm of resistance between the rear compartment lid latch assembly ground circuit terminal E and ground.
  10. If greater than the specified range, test the ground circuit for an open/high resistance.
  11. Connect the harness connector at the rear compartment lid latch assembly.
  12. Connect a 15-A fused jumper wire between the B+ circuit terminal C7 and the control circuit terminal D9. Verify the rear compartment lid latch motor is activated.
  13. If the rear compartment lid latch motor does not activate, test the control circuit for an open/high resistance. If the circuit tests normal, test or replace the rear compartment lid latch assembly.
  14. Connect a test lamp between the B+ circuit terminal D7 and the control circuit terminal C9.
  15. 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.
  16. 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.
  17. If all circuits test normal, test or replace the trunk release relay.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

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

Trunk Release Inoperative Coupe

Diagnostic Instructions

    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    •  Diagnostic Procedure Instructions provides an overview of each diagnostic category.

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

Trunk Key Switch Signal

3

3

3

--

Trunk Release Relay Control

4

4

B3265

--

Trunk Release Switch Signal - Exterior

B3618

2

2

--

Trunk Release Switch Signal - Interior

1

1

1

--

Rear Compartment Lid Pull Down Actuator B+

4

4

4

--

Rear Compartment Lid Pull Down Actuator Ground

4

4

4

--

Rear Compartment Lid Release Switch Exterior Ground

2

2

2

--

Rear Compartment Lid Release Switch Interior Ground

1

1

1

--

1. Trunk Release Inoperative from Interior Switch

2. Trunk Release Inoperative from Exterior Switch

3. Trunk Release Inoperative from Key Switch

4. Trunk Release Inoperative from All Switches

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. For more detailed information concerning trunk release operation refer to Luggage Compartment Description and Operation .

Reference Information

Schematic Reference

Release Systems Schematics

Connector End View Reference

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

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. Test for less than 1.0 ohm of resistance between the ground circuit terminal A and ground.
  3. If greater than the specified range, test the ground circuit for an open/high resistance.
  4. Ignition ON, verify the scan tool trunk release switch parameter is INACTIVE.
  5. If not the specified value, test the signal circuit terminal D for a short to ground. If the circuit tests normal, replace the BCM.
  6. 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.
  7. 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.
  8. 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. Test for less than 1.0 ohm of resistance between the ground circuit terminal A and ground.
  3. If greater than the specified range, test the ground circuit for an open/high resistance.
  4. Ignition ON, verify the scan tool Exterior Rear Compartment Lid Release Switch parameter is INACTIVE.
  5. 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).
  6. 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.
  7. 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).
  8. 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. Test for less than 1.0 ohm of resistance between the ground circuit terminal F and ground.
  3. If greater than the specified range, test the ground circuit for an open/high resistance.
  4. Ignition ON, verify the scan tool Trunk Key Cylinder Switch parameter is INACTIVE.
  5. If not the specified value, test the signal circuit terminal E for a short to ground. If the circuit tests normal, replace the BCM.
  6. 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.
  7. 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.
  8. 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. Test for less than 1.0 ohm of resistance between the ground circuit terminal F and ground.
  3. If greater than the specified range, test the ground circuit for an open/high resistance.
  4. Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal H and ground.
  5. 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.
  6. Connect a test lamp between the control circuit terminal B and the B+ circuit terminal H.
  7. 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.
  8. 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.
  9. If all circuits test normal, test or replace the rear compartment lid pull down actuator.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Rear Compartment Lid Lock Cylinder Replacement
    •  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