Service Information

Cruze

DTC B3125, B3130, or B3135

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 B3125 02: Driver Door Only Unlock Circuit Short to Ground

DTC B3130 02: All Doors Unlock Circuit Short to Ground

DTC B3135 02: All Doors Lock Circuit Short to Ground

Diagnostic Fault Information

Circuit	Short to Ground	Open/High Resistance	Short to Voltage	Signal Performance
BCM B+	B3125 02, B3130 02, B3135 02	B3125 02, B3130 02, B3135 02	--	--
Door Catch Control	B3125 02, B3130 02, B3135 02	2	2	--
Driver Door Lock Motor Lock Control	B3125 02, B3130 02, B3135 02	1	1	--
Door Lock Actuator Unlock Control	B3125 02, B3130 02, B3135 02	1, 2	1, 2	--
1. Driver Door Lock Malfunction 2. Passenger/Rear Door Lock Malfunction

The body control module (BCM) controls the driver and passenger door latches. When the BCM receives a driver door unlock, passenger door unlock or all door lock command, it will provide voltage to the appropriate door lock circuits and ground to the opposite door lock circuits causing the actuator to perform the lock or unlock function.

Conditions for Running the DTC

When the output is actively being requested by the BCM.

Conditions for Setting the DTC

B3125 02, B3130 02 and B3135 02

•	A short to ground or an open/high resistance in the BCM B+ circuit.

•	The BCM detects a short to ground on a door latch control circuit.

Action Taken When the DTC Sets

The power door locks will be inoperative.

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

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

Command the doors to LOCK and UNLOCK by using the central door lock switch, the doors should LOCK and UNLOCK when changing between the commanded states.

Circuit/System Testing

Ignition OFF, disconnect the X2 harness connector at the K9 BCM.
Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal 4 and ground.

⇒	If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance. If the circuit tests normal and the B+ circuit fuse is open, replace the K9 BCM.

Ignition OFF, connect the X2 harness connector and disconnect the X6 harness connector at the K9 BCM.
Disconnect the X2 harness connector at the X50A fuse block-underbonnet.
Test for infinite resistance between the control circuit listed below and ground:

•	Connector X2, terminal 53 at the X50A fuse block-underbonnet

•	Connector X2, terminal 50 at the X50A fuse block-underbonnet

•	Connector X6 terminal 4 at the K9 BCM

•	Connector X6 terminal 2 at the K9 BCM

⇒	If not the specified value, test the appropriate control circuit for a short to ground. If the circuit tests normal, test or replace the appropriate A23 door latch assembly.

Connect the X2 harness connector at the X50A fuse block-underbonnet.
Test for infinite resistance between the control circuit terminal 1 at the K9 BCM and ground.

⇒	If not the specified value, test the control circuit for a short to ground. If the circuit tests normal, replace the X50A fuse block-underbonnet.

If all circuits test normal, replace the K9 BCM.

Component Testing

Ignition OFF, disconnect the wiring harness plug at the appropriate A23 door latch assembly.
Install a 25 A fused jumper wire between one of the control terminals and 12 V. Momentarily install a jumper wire between the other control terminal and ground. Reverse the jumper wires at least two times, the A23 door latch assembly should perform the LOCK and UNLOCK functions.

⇒	If it does not perform as specified, replace the A23 door latch assembly

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

•	Front Side Door Catch Replacement

•	Rear Side Door Catch Replacement

•	Fuse Block Replacement

•	Control Module References for BCM replacement, programming and setup