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B3125




Power Door Lock Malfunction - 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 01

-
Driver Door Only Unlock Circuit Short to Battery

DTC B3125 02

-
Driver Door Only Unlock Circuit Short to Ground

DTC B3125 04

-
Driver Door Only Unlock Circuit Open

DTC B3130 01

-
All Doors Unlock Circuit Short to Battery

DTC B3130 02

-
All Doors Unlock Circuit Short to Ground

DTC B3130 04

-
All Doors Unlock Circuit Short Open

DTC B3135 01

-
All Doors Lock Circuit Short to Battery

DTC B3135 02

-
All Doors Lock Circuit Short to Ground

DTC B3135 04

-
All Doors Lock Circuit Open

Diagnostic Fault Information






Circuit/System Description

The body control module (BCM) powers the reversible door latch assemblies by providing battery positive voltage and ground to the appropriate lock and unlock control circuits of the door latch assemblies. The lock and unlock control circuits of the rear doors and passenger door latch assemblies are all connected together. When the door latch assemblies are not active, all actuator lock and unlock control circuits are at ground potential within the BCM. Transitioning of the lock actuators to the lock or unlocked position depends upon which control circuits receive voltage and which control circuits receive ground.

Conditions for Running the DTC

Ignition ON.

Conditions for Setting the DTC

B3125 01, B3130 01, B3135 01

The BCM detects a short to battery on a door latch control circuit

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.

B3125 04, B3130 04, B3135 04

The BCM detects an open/high resistance 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

* Body Control System Schematics [1][2]Body Control Systems

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, all the doors should LOCK and UNLOCK when changing between the commanded states.

If the driver door does not LOCK or UNLOCK, refer to Driver Door Lock Malfunction.

If one or more passenger doors do not LOCK or UNLOCK, refer to Passenger Door Lock Malfunction.

If all doors do not LOCK and UNLOCK, refer to All Door Locks Inoperative.

Circuit/System Testing

Driver Door Lock Malfunction

1. Ignition OFF, disconnect the harness connector at the A23D door latch assembly-driver.

2. Connect a test lamp between the control circuit terminal 2 and control circuit terminal 3

3. Command the driver door latch to LOCK and UNLOCK with a scan tool, the test lamp should illuminate when commanding the LOCK and UNLOCK states.

• If the test lamp is OFF during either of the LOCK and UNLOCK commands, test either control circuit for an open/high resistance. If the circuits test normal, replace the K9 body control module.

• If the test lamp always ON , test either control circuit for a short to voltage. If the circuits test normal, replace the K9 body control module.

4. If all circuits test normal, test or replace the A23D door latch assembly-driver

Passenger Door Lock Malfunction

1. Ignition OFF, disconnect the harness connector at the appropriate A23 door latch assembly.

2. Connect a test lamp between the control circuit terminals listed below:

* A23P door latch assembly-passenger control circuit terminal 7 and control circuit terminal 8

* A23RR door latch assembly-right rear control circuit terminal 7 and control circuit terminal 8

* A23LR door latch assembly-left rear control circuit terminal 2 and control circuit terminal 3

3. Command the door to LOCK and UNLOCK with a scan tool, the test lamp should illuminate when commanding the LOCK and UNLOCK states.

• If the test lamp is OFF during either of the LOCK and UNLOCK commands, test either control circuit for an open/high resistance. If the circuits test normal, replace the K9 body control module.

• If the test lamp always ON , test either control circuit for a short to voltage. If the circuits test normal, replace the K9 body control module.

4. If all circuits test normal, test or replace the A23 door latch assembly

All Door Locks Inoperative

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

2. 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.

3. Ignition OFF, connect the X2 harness connector at the K9 body control module.

4. Disconnect the X6 harness connector at the K9 body control module.

5. Disconnect the KR113 rear door handle disable relay.

6. Test for infinite resistance between the control circuit listed below and ground:

* Terminal 2 at the KR113 rear door handle disable relay.

* Terminal 4 at the KR113 rear door handle disable relay

* Terminal 1 X6 at the K9 BCM

* Terminal 4 X6 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.

7. Connect the KR113 rear door handle disable relay.

8. 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, test or replace the KR113 rear door handle disable relay.

9. If all circuits test normal, replace the K9 body control module.

Component Testing

Door Latch

1. Ignition OFF, disconnect the harness connector at the appropriate A23 door latch assembly.

2. 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 door latch should perform the LOCK and UNLOCK functions.

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

Relay Test

1. Ignition OFF, disconnect the KR113 rear door handle disable relay.

2. Test for 60-180 ohms between terminals 1 and 2.

• If the not within the specified range, replace the KR113 rear door handle disable relay.

3. Test for infinite resistance between the following terminals:

* 3 and 2

* 3 and 5

* 3 and 1

* 1 and 5

• If not the specified value, replace the KR113 rear door handle disable relay.

4. Install a 5 A fused jumper wire between relay terminal 2 and 12 V. Install a jumper wire between relay terminal 1 and ground. Test for less than 2 ohms between terminals 3 and 5.

• If greater than the specified range, replace the KR113 rear door handle disable relay.

Repair Instructions

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

* Hazard Warning Switch Replacement Service and Repair

* Front Side Door Lock Replacement Front Side Door Lock Replacement

* Rear Side Door Lock Replacement Rear Side Door Lock Replacement

* Relay Replacement (Within an Electrical Center) Relay Replacement (Within an Electrical Center)Relay Replacement (Attached to Wire Harness) Relay Replacement (Attached to Wire Harness)

* Control Module References Programming and Relearning for BCM replacement, programming and setup

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