B251A
DTC B251A-B251F
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 Instructionsprovides an overview of each diagnostic category.
DTC Descriptors
DTC B251A 01
- All Door Unlatch Circuit Short to Battery
DTC B251A 02
- All Door Unlatch Circuit Short to Ground
DTC B251B 04
- Driver Door Unlatch High Control Circuit Open
DTC B251C 04
- Passenger Door Unlatch High Control Circuit Open
DTC B251D 04
- Left Rear Door Unlatch High Control Circuit Open
DTC B251E 04
- Right Rear Door Unlatch High Control Circuit Open
Diagnostic Fault Information
Circuit/System Description
When any exterior door handle is lifted, switched ground signals are sent to the keyless entry control module through the door handle switch signal circuits. Upon receipt of these inputs, the keyless entry control module will check the door lock status of the following inputs:
* Door unlock switch activation
* Keyless entry unlock command
* Passive keyless entry unlock command message is received by the keyless entry control module
Once the enable criteria has been met, the keyless entry control module will supply power and ground to door latch control circuits and the door will release.
Conditions for Running the DTC
Battery voltage is between 9-16 V.
Conditions for Setting the DTC
B251A 01
The keyless entry control module detects a short to voltage in any door unlatch motor unlatch control low circuit.
B251A 02
The keyless entry control module detects a short to ground in any door unlatch motor unlatch control low circuit.
B251B 04
The keyless entry control module detects an open in the driver door unlatch motor unlatch control low or high circuit.
B251C 04
The keyless entry control module detects an open in the passenger door unlatch motor unlatch control low or high circuit.
B251D 02
The keyless entry control module detects an open in the left rear door unlatch motor unlatch control low or high circuit.
B251E 04
The keyless entry control module detects an open in the right rear door unlatch motor unlatch control low or high circuit.
Action Taken When the DTC Sets
The keyless entry control module ignores inputs from the exterior door handle switches.
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 Door Lock/Indicator Schematics
Connector End View Reference
Component Connector End Views Sunshade - Left (D6I)
Description and Operation
Power Door Latch 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 Control Module Referencesfor scan tool information
Circuit/System Verification
Ignition ON, command the body control module Driver Door Unlatch and Passenger Door(s) Unlatch with the scan tool. The driver and passenger door latches should unlatch when changing between commanded states.
Circuit/System Testing
1. Ignition OFF, disconnect the harness connector at the malfunctioning door latch assembly.
2. Ignition ON, verify that a test lamp does not illuminate between control circuit terminal 5 and ground.
• If the test lamp illuminates, test the control circuit for a short to voltage. If the circuit tests normal. replace the K84 Keyless Entry Control Module.
3. Verify that a test lamp does not illuminate between control circuit terminal 10 and ground.
• If the test lamp illuminates, test the control circuit for a short to voltage. If the circuit tests normal. replace the K84 Keyless Entry Control Module.
4. Verify that a test lamp does not illuminate between control circuit terminal 5 and B+.
• If the test lamp illuminates, test the control circuit for a short to ground. If the circuit tests normal. replace the K84 Keyless Entry Control Module.
5. Verify that a test lamp does not illuminate between control circuit terminal 10 and B+.
• If the test lamp illuminates, test the control circuit for a short to ground. If the circuit tests normal. replace the K84 Keyless Entry Control Module.
6. Connect a test lamp between the control circuit terminals 5 and 10.
7. Verify the test lamp illuminates briefly, while pulling the exterior door handle.
• If the test lamp does not illuminate, test the control circuits for an open/high resistance. If the circuits test normal, replace K84 Keyless Entry Control Module.
8. If all circuits test normal, test or replace the door latch assembly.
Component Testing
Door Latch Assembly Test
1. Ignition OFF, disconnect the harness connector at the appropriate door latch assembly.
2. Ignition ON, install a 15 A fused jumper wire between the control terminal listed below and B+:
* Left hand drive: Driver door latch control terminal 10
* Left hand drive: Passenger door latch control terminal 5
* Right hand drive: Driver door latch control terminal 5
* Right hand drive: Passenger door latch control terminal 10
* Left rear door latch control terminal 10
* Right rear door latch control terminal 5
3. Momentarily install a jumper wire between the control terminal listed below and ground. The door latch should perform the Unlock function:
* Left hand drive: Driver door latch control terminal 5
* Left hand drive: Passenger door latch control terminal 10
* Right hand drive: Driver door latch control terminal 10
* Right hand drive: Passenger door latch control terminal 5
* Left rear door latch control terminal 5
* Right rear door latch control terminal 10
• If the function does not perform as specified, replace the door latch assembly.
4. Reverse the jumper wires; the door latch assembly should perform the Lock function.
• If the function does not perform as specified, replace the 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
* Control Module References Control Module Referencesfor keyless entry control module replacement, setup, and programming