B3135
DTC B3125, B3130, or B3135
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 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/System Description
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
Ignition ON.
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
All power door locks will be inoperative.
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
Door Lock/Indicator Schematics (Door Lock/Indicator Schematics)
Connector End View Reference
Component Connector End Views (Connector End Views By Name)
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 (Programming and Relearning) 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
1. Ignition OFF, disconnect the X2 and X5 harness connectors at the K9 BCM.
2. Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal listed below and ground:
* B+ circuit terminal 3 X5
* B+ circuit terminal 4 X2
• If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
3. Ignition OFF, connect the X2 harness connector and disconnect the X6 harness connector at the K9 BCM.
4. Disconnect the X2 harness connector at the X50A fuse block-underhood.
5. Test for infinite resistance between the control circuit listed below and ground:
* Connector X2, terminal 4 at the X50A fuse block-underhood
* Connector X2, terminal 5 at the X50A fuse block-underhood
* Connector X6 terminal 1 at the K9 BCM
* Connector X6 terminal 4 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.
6. Connect the X2 harness connector at the X50A fuse block-underhood.
7. Test for infinite resistance between the control circuit terminal 2 X6 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-underhood.
8. If all circuits test normal, replace the K9 BCM.
Component Testing
Door Latch Test
1. Ignition OFF, disconnect the harness connector at the appropriate A23 door latch assembly.
2. Install a 15 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 appropriate A23 door latch assembly
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
* Front Side Door Latch Replacement (Service and Repair)
* Rear Side Door Latch Replacement (Service and Repair)
* Fuse Block Replacement (Fuse Block Replacement)
* Control Module References (Programming and Relearning) for BCM replacement, programming and setup