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.

### Diagnostic Fault Information

Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance
--- | --- | --- | --- | ---
Door Ajar Signal Circuit | 1 | 2 | -- | --
Door Ajar Ground Circuit | -- | 2 | 2 | --
1. Door Ajar Light Stays On 2. Door Ajar Light Will Not Come On

### Circuit/System Description

The body control module (BCM) receives a discrete input from the respective jamb switch to indicate the status of the door. The BCM then communicates this status to the instrument panel cluster (IPC) via a serial data message. The IPC, upon receipt of this serial data message, will illuminate the appropriate ajar message in the driver information center (DIC) and also send a serial data massage to the radio to activate the door ajar audible warning when the transmission is removed from PARK and the vehicle speed is greater then 8.05 km/h (5 mph).

### Diagnostic Aids

The door ajar switches supply a ground to the BCM when the door is open. Once the door is closed the door ajar switch opens canceling the ground to the BCM. The BCM sends a signal to the IPC to turn on the door ajar light when a door is open.

### Reference Information

#### Schematic Reference

Door Lock/Indicator Schematics

#### Connector End View Reference

• | Vehicle Access Connector End Views

• | Data Communication Connector End Views

#### Electrical Information Reference

• | Circuit Testing

• | Connector Repairs

• | Testing for Intermittent Conditions and Poor Connections

• | Wiring Repairs

#### Scan Tool Reference

• | Scan Tool Data List

• | Scan Tool Data Definitions

### Circuit/System Verification

Ignition ON, observe the scan tool Door Ajar Sw parameter while opening and closing all doors. The reading should change between Door Ajar and Door Closed.

### Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the appropriate door latch assembly.
2. Test for less than 1 ohm of resistance between the appropriate door ajar switch ground circuit terminal H and ground.

⇒ | If greater than the specified range, test the ground circuit for an open/high resistance.

3. Ignition ON, doors closed, verify the scan tool Door Ajar Sw parameter for the appropriate door is Door Closed.

⇒ | If not the specified value, test the appropriate door ajar switch signal circuit for a short to ground. If the circuit tests normal, replace the BCM.

4. Install a 3A fused jumper wire between the appropriate door ajar switch signal circuit terminal H and ground. Verify the scan tool Door Ajar Sw parameter is Door Ajar.

⇒ | If not the specified value, test the appropriate door ajar switch signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the BCM.

5. If all circuits test normal, test or replace the appropriate door latch assembly.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• | Front Side Door Latch Replacement

• | Rear Side Door Latch Replacement

• | Control Module References for IPC and BCM replacement, setup, and programming