For 1990-2009 cars

### 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 Descriptor

DTC B250B 01: Driver Door Unlatch Low Control Circuit Short to Battery
DTC B250B 02: Driver Door Unlatch Low Control Circuit Short to Ground

### Diagnostic Fault Information

Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance
--- | --- | --- | --- | ---
Driver Exterior Door Lock Switch Signal | B2516 02 | 1 | 1 | --
Driver Door Unlatch High Control | 2 | 2 | B250B 01 | --
Driver Door Unlatch Low Control | B250B 02 | 2 | B250B 01 | --
1. Door Lock Malfunction 2. Door Latch Malfunction

### Circuit/System Description

When any exterior door handle is lifted, switched ground signals are sent to the remote control door lock receiver through the door handle switch signal circuits. Upon receipt of these inputs, the remote control door lock receiver 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 remote control door lock receiver

Once the enable criteria has been met, the remote control door lock receiver 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

#### B250B 01

The remote control door lock receiver detects a short to battery in the driver door unlatch motor unlatch control low circuit.

#### B250B 02

The remote control door lock receiver detects a short to ground in the driver door unlatch motor unlatch control low circuit.

### Action Taken When the DTC Sets

The remote control door lock receiver ignores inputs from the driver exterior door handle switch.

### 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

#### Connector End View Reference

Component Connector End Views

#### Description and Operation

Power Door Locks Description and Operation

#### 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

Ignition ON, command the Driver Door PEPS Release to Lock and Unlock. The driver door latch should Latch and Unlatch when changing between commanded states.

### Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the A23D Door Latch Assembly - Driver.
2. Test for less than 10 Ω between the control circuit terminal 10 and ground.

⇒ | If greater than the specified range, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K77 Remote Control Door Lock Receiver.

3. Test for less than 10 Ω between the control circuit terminal 5 and ground.

⇒ | If greater than the specified range, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K77 Remote Control Door Lock Receiver.

4. Connect a test lamp between the control circuit terminals 5 and 10.
5. Command the Driver Door PEPS Release to Lock and Unlock with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states.

⇒ | If the test lamp is always OFF during either of the commands, test either control circuit for a short to ground. If the circuits test normal, replace K77 Remote Control Door Lock Receiver.

6. If all circuits test normal, test or replace the A23D Door Latch Assembly - Driver.

### Component Testing

#### Driver Door Latch Test

1. Ignition OFF, disconnect the harness connector at the A23D Door Latch Assembly - Driver.
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 door latch should perform the Lock/Unlock functions.

⇒ | If it does not perform as specified, replace the A23D Door Latch Assembly - Driver.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• | Front Side Door Lock Replacement

• | Control Module References for remote control door lock receiver replacement, setup, and programming