GM Service Manual Online
For 1990-2009 cars only

Diagnostic Instructions

    • Perform the prior to Diagnostic System Check - Vehicle 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 B3265 02: Trunk Lid Unlatch Output Circuit Short to Ground

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

Trunk Relay B+

1

1

--

--

Rear Compartment Lid Exterior Release Switch Signal

B3618 00

2

B3618 00

--

Rear Compartment Lid Release Actuator Control

1

1

1

--

Trunk Release Relay Control

B3265 02

1,2

1

--

Rear Compartment Lid Release Actuator Ground

--

1

1

--

Rear Compartment Lid Exterior Release Switch Ground

--

B3618 00

B3618 00

--

Trunk Relay Ground

--

1

1

--

1. Trunk Release Malfunction

2. Trunk Release Exterior Switch Malfunction

Circuit/System Description

The body control module (BCM) applies battery positive voltage to the trunk release relay control circuit, which energizes the coil side of the rear compartment lid release relay. The switch side of the rear compartment lid release relay then closes, supplying battery positive voltage through the relay and the latch motor voltage control circuit to the rear compartment lid latch. The rear compartment lid latch then releases the rear compartment lid so that it may be manually raised to an open position.

Conditions for Running the DTC

Battery voltage must be between 9-16 V.

Conditions for Setting the DTC

The BCM detects a short to ground on the trunk release relay control circuit.

Action Taken When the DTC Sets

The rear compartment latch will not operate.

Conditions for Clearing the DTC

    • This 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

Ignition ON, command the trunk release with a scan tool. The rear compartment lid actuator should release the trunk lid.

Circuit/System Testing

  1. Ignition OFF, disconnect the KR95B Rear Compartment Lid Release Relay.
  2. Ignition ON, verify that a test lamp does not illuminate between the control circuit terminal 85 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 ground circuit terminal 86 and B+.
  5. If the test lamp does not illuminate, test the ground circuit for a short to voltage or an open/high resistance. If the circuit tests normal, test or replace the KR95B Rear Compartment Lid Release Relay.
  6. Verify that a test lamp illuminates between the B+ circuit terminal 30 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 M41 Rear Compartment Lid Latch Release Actuator.
  9. Test for less than 2 Ω between the M41 Rear Compartment Lid Latch Release Actuator connector terminal 1 and ground.
  10. If greater than the specified range, test the rear compartment lid release circuit for an open/high resistance.
  11. Connect the harness connector at the M41 Rear Compartment Lid Latch Release Actuator.
  12. Connect a 15 A fused jumper wire between the B+ terminal 30 and the control circuit terminal 87A. Verify the M41 Rear Compartment Lid Latch Release Actuator is activated.
  13. If the M41 Rear Compartment Lid Latch Release Actuator does not activate, test the control circuit for an open/high resistance. If the circuit tests normal, test or replace the M41 Rear Compartment Lid Latch Release Actuator.
  14. Connect a DMM, set on the diode setting, between the control circuit terminal 86 and ground.
  15. Command the Trunk Lid Release Unlatch with a scan tool. The DMM reading should be greater than 2.5 V or display O.L.
  16. If less than the specified value, test the control circuit for a short to voltage or short to ground. If the circuits test normal, replace the K9 Body Control Module (BCM).
  17. Command the Trunk Lid Release Latch with a scan tool. The DMM reading should be less than 1 V.
  18. If greater than the specified range, test the control circuit for an open/high resistance. If the circuit tests normal, replace the K9 Body Control Module (BCM).
  19. If all circuits test normal, test or replace the KR95B Rear Compartment Lid Release Relay.

Component Testing

Relay Test

  1. Ignition OFF, disconnect the KR95B Rear Compartment Lid Release Relay.
  2. Test for 60-180 Ω between terminals 85 and 86.
  3. If the resistance is not within the specified range, replace the KR95B Rear Compartment Lid Release Relay.
  4. Test for infinite resistance between the following terminals:
  5. • 30 and 86
    • 30 and 87
    • 30 and 85
    • 85 and 87
    If not the specified value, replace the KR95B Rear Compartment Lid Release Relay.
  6. Install a 15 A fused jumper wire between relay terminal 85 and 12 V. Install a jumper wire between relay terminal 86 and ground. Test for less than 2 Ω between terminals 30 and 87.
  7. If greater than the specified range, replace the KR95B Rear Compartment Lid Release Relay.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

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