GM Service Manual Online
For 1990-2009 cars only

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.

DTC Descriptor

DTC B2494 02: Liftgate Handle Switch Circuit Short to Ground

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

Rear Compartment Lid Release Switch Signal

B1543 02

1

1

--

Rear Compartment Lid Release Switch Ground

--

1

1

--

1. Trunk Lid Release Malfunction

Circuit/System Description

The exterior rear compartment lid release switch receives a signal from the body control module (BCM). When the exterior rear compartment lid release switch is activated the signal circuit is pulled to ground. The BCM applies battery positive voltage to the trunk release relay control circuit which energizes the relay. The trunk release relay is grounded at all times. With the relay coil energized, the relay switch contacts close allowing battery voltage to flow to the rear compartment lid release actuator causing the rear compartment lid to release.

Conditions for Running the DTC

Battery voltage is between 9-16 volts.

Conditions for Setting the DTC

The BCM detects the exterior rear compartment lid release switch signal circuit is shorted to ground or closed for more than 180 seconds.

Action Taken When the DTC Sets

The BCM ignores inputs from the exterior rear compartment lid release switch.

Conditions for Clearing the DTC

    • The DTC will be current for as long as the fault is present.
    • When the fault is no longer present, the DTC will be a history DTC.
    • A history DTC will clear after 50 ignition cycles.

Reference Information

Schematic Reference

Release Systems Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Luggage Compartment Description and Operation

Electrical Information Reference

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

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

  1. Ignition ON, command the trunk release with a scan tool. The rear compartment lid latch should release the trunk lid.
  2. If the rear compartment lid latch is inoperative, refer to Rear Compartment Lid Malfunction.
  3. Command the trunk release by using the exterior rear compartment lid release switch. The rear compartment lid latch should release the trunk lid.

Circuit/System Testing

  1. Ignition OFF, disconnect the harness connector at the S58A Rear Compartment Lid Release Switch - Exterior.
  2. Test for less than 1 Ω between the ground circuit terminal 3 and ground.
  3. If greater than the specified range, test the ground circuit for an open/high resistance.
  4. Connect the harness connector at the S58A Rear Compartment Lid Release Switch - Exterior and disconnect the X6 harness connector at the K9 Body Control Module (BCM).
  5. Connect a test lamp between the signal circuit terminal 15 and B+.
  6. Ignition ON, command the trunk release ON and OFF by pressing and releasing the exterior rear compartment lid release switch. The test lamp should turn ON and OFF when changing between the commanded states.
  7. If the test lamp continuously illuminates, test the signal circuit for a short to ground or and open/high resistance. If the circuit tests normal, replace the S58A Rear Compartment Lid Release Switch - Exterior.
    If the test lamp does not illuminate, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the S58A Rear Compartment Lid Release Switch - Exterior.
  8. If all circuits test normal, replace the K9 Body Control Module (BCM).

Component Testing

Rear Compartment Lid Latch

  1. Ignition OFF, disconnect the harness connector at the M41 Rear Compartment Lid Latch Release Actuator.
  2. Install a 15A fused jumper wire between the control terminal 1 and 12 V. Install a jumper wire between the ground terminal 2 and ground. Verify the M41 Rear Compartment Lid Latch Release Actuator activates.
  3. If the actuator does not perform as specified, replace the M41 Rear Compartment Lid Latch Release Actuator.

Rear Compartment Lid Release Switch

  1. Ignition OFF, disconnect the harness connector at the S58A Rear Compartment Lid Release Switch - Exterior.
  2. Test for infinite resistance between the signal terminal 1 and the ground terminal 3 with the switch in the open position.
  3. If not the specified value, replace the S58A Rear Compartment Lid Release Switch - Exterior.
  4. Test for less than 2 Ω between the signal terminal 1 and the ground terminal 3 with the switch in the closed position.
  5. If greater than the specified range, replace the S58A Rear Compartment Lid Release Switch - Exterior.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Rear Compartment Lid Release Switch Replacement
    •  Rear Compartment Lid Latch Replacement
    •  Control Module References for BCM replacement, setup, and programming