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B3125



DTC B3125

DTC Descriptor
DTC B3125 00
- All Door Lock Circuit

Diagnostic Fault Information

Important: Always perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Initial Inspection and Diagnostic Overview





Circuit/System Description

When the door lock switch is place in to the LOCK position, ground is applied through the switch to the body control module (BCM). The BCM then applies a voltage through the door lock relay control circuit to the coil side of the lock relay in the body electrical center (BEC). The relay then engages and applies voltage to all the door lock assemblies.

Conditions for Running the DTC

The ignition is ON.

Conditions for Setting the DTC

The BCM receives a ground signal on the door lock relay control circuit

Action Taken When the DTC Sets

The BCM cease attempt to lock the doors.

Conditions for Clearing the DTC

The BCM clears this code from current when the fault is removed from the system.

Circuit/System Verification

Ignition ON, place the door lock switch to the LOCK position. All doors should lock.

Circuit/System Testing

1. Disconnect the Lock relay in the BEC. Verify the DTC resets.

If the DTC does not reset, replace the relay.

2. Disconnect the BEC connector C1. Verify the DTC resets.

If the DTC does not reset, replace the BEC.

3. Test for a short to ground in the door lock relay control circuit.

If all circuits/connections test normal, replace the BCM.

Repair Instructions

Important: Always perform the Diagnostic Repair Verification after completing the diagnostic procedure.

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