Chevrolet Trax: DTC B3140, B3145, B3150, OR B3155: Door lock/unlock switch

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 Descriptors

DTC B3140 00

Driver Door Unlock Switch Circuit

DTC B3145 00

Passenger Door Unlock Switch Circuit

DTC B3150 00

Driver Front Door Lock Switch Circuit

DTC B3155 00

Passenger Front Door Lock Switch Circuit

Diagnostic Fault Information

Circuit/System Description

The body control module (BCM) supplies a 12 V signal to each of the door lock and door unlock signal circuits.

When the door lock switches are in the open position, the voltage level in the signal circuit will be near 12 V.

When any 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 driver unlock signal circuit for greater than 30 seconds.

B3145 00

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

B3150 00

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

B3155 00

The BCM detects a short to ground in the passenger 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 driver door unlock switch.

B3145 00

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

B3150 00

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

B3155 00

The BCM will ignore the lock signal and the doors will not lock when using the passenger 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 (Encore), Door Lock/Indicator Schematics (Trax)

Connector End View Reference

WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX - ENCORE WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX - TRAX

Description and Operation

Power Door Locks 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.
2. Verify the scan tool Driver Door Lock Switch parameter changes from Inactive to Lock and Unlock when pushing the appropriate switch on the S13D Door Lock Switch - Driver.

• If the parameter does not change

Refer to Circuit/System Testing - Driver Door Lock Switch Malfunction.

• If the parameter changes

3. Verify the scan tool Passenger Door Lock Switch parameter changes from Inactive to Lock and Unlock when pushing the appropriate switch on the S13P Door Lock Switch - Passenger.

• If the parameter does not change

Refer to Circuit/System Testing - Passenger Door Lock Switch Malfunction.

• If the parameter changes

4. All OK.

Circuit/System Testing

Driver Door Lock Switch Malfunction

1. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the S13D Door Lock Switch - Driver. 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 3 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 Driver Door Lock Switch parameter is Inactive.

If not Inactive

1. Ignition OFF, disconnect the harness connector at the K9 Body Control Module.
2. Test for infinite resistance between the signal circuit terminal 4 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 2 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 4 and the ground circuit terminal 3.
6. Verify the scan tool Driver Door Lock Switch parameter is Lock.

• If not Lock

1. Ignition OFF, remove the 3 A fused 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

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

7. Install a 3 A fused jumper wire between the signal circuit terminal 2 and the ground circuit terminal 3.
8. Verify the scan tool Driver Door Lock Switch parameter is Unlock.

• If not Unlock

1. Ignition OFF, 3 A fused 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

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

9. Test or replace the S13D Door Lock Switch - Driver.

Passenger Door Lock Switch Malfunction

1. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the S13P Door Lock Switch - Passenger. 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 3 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 Passenger Door Lock Switch parameter is Inactive.

• If not Inactive

1. Ignition OFF, disconnect the harness connector at the K9 Body Control Module.
2. Test for infinite resistance between the signal circuit terminal 4 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 2 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 4 and the ground circuit terminal 3.
6. Verify the scan tool Passenger Door Lock Switch parameter is Lock.

• If not Lock

1. Ignition OFF, 3 A fused 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

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

7. Install a 3 A fused jumper wire between the signal circuit terminal 2 and the ground circuit terminal 3.
8. Verify the scan tool Passenger Door Lock Switch parameter is Unlock.

If not Unlock

1. Ignition OFF, 3 A fused 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

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

9. Test or replace the S13P Door Lock Switch - Passenger.

Component Testing

Driver Door Lock Switch

1. Ignition OFF, disconnect the harness connector at the S13D Door Lock Switch - Driver.
2. Test for infinite resistance between the signal terminal 2 and the ground terminal 3 with the switch in the center position.

• If less than infinite resistance

Replace the S13D Door Lock Switch - Driver.

• If infinite resistance

3. Test for infinite resistance between the signal terminal 4 and the ground terminal 3 with the switch in the center position.

• If less than infinite resistance

Replace the S13D Door Lock Switch - Driver

• If infinite resistance

4. Test for less than 2 ohms between the signal terminal 4 and the ground terminal 3 with the switch in the Lock position

• If 2 ohms or greater

Replace the S13D Door Lock Switch - Driver.

• If less than 2 ohms

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

• If 2 ohms or greater

Replace the S13D Door Lock Switch - Driver.

• If less than 2 ohms

6. All OK

Passenger Door Lock Switch

1. Ignition OFF, disconnect the harness connector at the S13P Door Lock Switch - Passenger.
2. Test for infinite resistance between the signal terminal 2 and the ground terminal 3 with the switch in the center position

• If less than infinite resistance

Replace the S13P Door Lock Switch - Passenger.

• If infinite resistance

3. Test for infinite resistance between the signal terminal 4 and the ground terminal 3 with the switch in the center position.

• If less than infinite resistance

Replace the S13P Door Lock Switch - Passenger

• If infinite resistance

4. Test for less than 2 ohms between the signal terminal 4 and the ground terminal 3 with the switch in the Lock position.

• If 2 ohms or greater

Replace the S13P Door Lock Switch - Passenger.

• If less than 2 ohms

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

• If 2 ohms or greater

Replace the S13P Door Lock Switch - Passenger.

• If less than 2 ohms

6. All OK

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• Door Lock Switch Replacement - Driver Side (Encore), Door Lock Switch Replacement - Driver Side (Trax)
• Door Lock Switch Replacement - Passenger Front (Encore), Door Lock Switch Replacement - Passenger Front (Trax)
• Control Module References for BCM replacement, programming and setup

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