B3150

DTC B3140 or B3150

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 Descriptors

DTC B3140 00
- Driver Door Unlock Switch Circuit

DTC B3150 00
- Left Front Door Lock Switch Circuit

Diagnostic Fault Information






Circuit/System Description

The body control module (BCM) monitors the voltage level of the door lock and door unlock signal circuits. When the central door lock switch is in the open position, the voltage level in the signal circuit will be near 12 V. When the central door lock switch is pressed to the lock or unlock position, the voltage level in the appropriate signal circuit will drop to 0 V and the BCM will detect the voltage drop and command the door latches to perform the requested lock or unlock command.

Conditions for Running the DTC

The system voltage is 9-16 V.

Conditions for Setting the DTC

B3140 00

The BCM detects short to ground in the unlock signal circuit for greater than 30 seconds.

B3150 00

The BCM detects a short to ground in the lock signal circuit for greater than 30 seconds.

Action Taken When the DTC Sets

B3140 00

The BCM will ignore the unlock signal and the doors will not unlock when using the central door lock switch.

B3150 00

The BCM will ignore the lock signal and the doors will not lock when using the central door lock 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

Door Lock/Indicator Schematics Door Lock/Indicator Schematics

Connector End View Reference

Component Connector End Views Sunshade - Left

Description and Operation

Power Door Locks 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 scan tool BCM Central Door Lock Switch on Console parameter changes from Inactive to Lock and Unlock when pushing the appropriate switch on the central door lock switch.

• If the parameter does not change
Refer to Circuit/System Testing.

• If the parameter changes

3. All OK.

Circuit/System Testing

1. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the S48C multifunction switch 1-instrument panel. 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 7 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. Verify the scan tool Central Door Lock Switch on Console parameter is Inactive.

• If not Inactive

1. Ignition OFF, disconnect the X2 harness connector at the K9 body control module.

2. Test for infinite resistance between the signal circuit terminal 12 and ground.

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

3. Test for infinite resistance between the signal circuit terminal 18 and ground.

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

• If infinite resistance, replace the K9 body control module.

• If Inactive

5. Install a 3 A fused jumper wire between the signal circuit terminal 9 and the ground circuit terminal 7.

6. Verify the scan tool Central Door Lock Switch on Console parameter is Unlock.

• If not Unlock

1. Ignition OFF, disconnect the X2 harness connector at the K9 body control module, ignition ON.

2. Test for less than 1 V between the signal circuit terminal 18 and ground.

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

• If less than 1 V

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

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

• If less than 2 ohms, replace the K9 body control module.

• If Unlock

7. Install a 3 A fused jumper wire between the signal circuit terminal 11 and the ground circuit terminal 7.

8. Verify the scan tool Central Door Lock Switch on Console parameter is Lock.

• If not Lock

1. Ignition OFF, disconnect the X2 harness connector at the K9 body control module, ignition ON.

2. Test for less than 1 V between the signal circuit terminal 12 and ground.

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

• If less than 1 V

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

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

• If less than 2 ohms, replace the K9 body control module.

• If Lock

9. Test or replace the S48C multifunction switch 1-instrument panel.

Component Testing

1. Ignition OFF, disconnect the harness connector at the S48C multifunction switch 1-instrument panel.

2. Test for infinite resistance between the signal terminal 9 and the ground terminal 7 with the switch in the open position.

• If less than infinite resistance
Replace the S48C multifunction switch 1-instrument panel.

• If infinite resistance

3. Test for infinite resistance between the signal terminal 11 and the ground terminal 7 with the switch in the open position.

• If less than infinite resistance
Replace the S48C multifunction switch 1-instrument panel.

• If infinite resistance

4. Test for less than 2 ohms between the signal terminal 11 and the ground terminal 7 with the switch in the Lock position.

• If 2 ohms or greater
Replace the S48C multifunction switch 1-instrument panel.

• If less than 2 ohms

5. Test for less than 2 ohms between the signal terminal 9 and the ground terminal 7 with the switch in the Unlock position.

• If 2 ohms or greater
Replace the S48C multifunction switch 1-instrument panel.

• If less than 2 ohms

6. All OK

Repair Instructions

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

* Hazard Warning Switch Replacement Service and Repair

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