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B2730




DTC B2730

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.

DTC Descriptor

DTC B2730 00
- Interior Trunk Lid Unlatch Switch Circuit Malfunction

Diagnostic Fault Information






Circuit/System Description

When the ignition is ON, the body control module (BCM) supplies a 12 V signal to the rear compartment lid unlatch switch through the trunk release switch signal circuit. When the interior rear compartment lid release switch is pressed, the voltage within the signal circuit is pulled low and in response, the BCM will energize the trunk release relay.

Conditions for Running the DTC

The system voltage is 9-16 V.

Conditions for Setting the DTC

The BCM detects a short to ground in the interior rear compartment lid release switch signal circuit for greater than 60 seconds

Action Taken When the DTC Sets

The BCM ignores the input from the interior rear compartment lid unlatch switch.

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 Release Systems Schematics

Connector End View Reference

Component Connector End Views Fuel Pump and Level Sensor Assembly

Description and Operation

Luggage Compartment Description and Operation Description and Operation

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.

2. Verify the operation of the M40 Rear Compartment Lid Latch when commanding the Trunk Lid Unlatch with a scan tool.

If the M40 Rear Compartment Lid Latch does not Unlatch
Refer to Trunk Release Malfunction Trunk Release Malfunction

If the M40 Rear Compartment Lid Latch does Unlatch

3. Verify the operation of the M40 Rear Compartment Lid Latch when pressing and releasing the S58B Rear Compartment Lid Unlatch Switch-Interior.

If the M40 Rear Compartment Lid Latch does not Unlatch
Refer to Circuit/System Testing

If the M40 Rear Compartment Lid Latch does Unlatch

4. All OK.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the S58B Rear Compartment Lid Unlatch Switch-Interior. It may take up to 2 minutes for all vehicle systems to power down.

2. Test for less than 10 ohms between the ground circuit terminal 2 and ground.

If 10 ohms or greater

1. Ignition OFF.

2. Test for less than 2 ohms in the ground circuit end to end.

If 2 ohms or greater, repair the open/high resistance in the circuit.

If less than 2 ohms, repair the open/high resistance in the ground connection.

If less than 10 ohms

3. Ignition ON.

4. Test for greater than 10 V between the signal circuit terminal 1 and ground.

If 10 V or less

1. Ignition OFF, disconnect the harness connector at the K9 Body Control Module.

2. Test for infinite resistance between the signal circuit and ground.

If less than infinite resistance, repair the short to ground on the circuit.

If infinite resistance

3. Test for less than 2 ohms in the control circuit end to end.

If 2 ohms or greater, repair the open/high resistance on the circuit.

If less than 2 ohms, replace the K9 Body Control Module.

If greater than 10 V

5. Install a 3 A fused jumper wire between the signal circuit terminal 1 and the ground circuit terminal 2.

6. Verify the M40 Rear Compartment Lid Latch activates.

If the M40 Rear Compartment Lid Latch does not activate

1. Ignition OFF, remove the jumper wire, disconnect the harness connector at the K9 Body Control Module, ignition ON.

2. Test for less than 1 V between the signal circuit and ground.

If 1 V or greater, repair the short to voltage on the circuit.

If less than 1 V, replace the K9 Body Control Module.

If the M40 Rear Compartment Lid Latch activates

7. Test or replace the S58B Rear Compartment Lid Unlatch Switch-Interior.

Component Testing

1. Ignition OFF, disconnect the harness connector at the S58B Rear Compartment Lid Unlatch Switch-Interior.

2. Test for infinite resistance between the signal terminal 1 and the ground terminal 2 with the switch in the open position.

If less than infinite resistance
Replace the S58B Rear Compartment Lid Unlatch Switch-Interior.

If infinite resistance

3. Test for less than 3 ohms between the signal terminal 1 and the ground terminal 2 with the switch in the closed position.

If 3 ohms or greater
Replace the S58B Rear Compartment Lid Unlatch Switch-Interior.

If less than 3 ohms

4. All OK

Repair Instructions

Perform the Diagnostic Repair Verification Verification Tests after completing the repair.

* Rear Compartment Lid Release Switch Replacement Service and Repair

* Control Module References Control Module References for BCM replacement, programming and setup