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 B2991 00: Passenger Door Ajar Circuit

### Diagnostic Fault Information

Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance
--- | --- | --- | --- | ---
Driver Door Ajar Signal | B2976 00 | 1 | 1 | --
Passenger Door Ajar Signal | B2991 00 | 1 | 1 | --
Driver Door Latch Ground | -- | 1 | 1 | --
Passenger Door Latch Ground | -- | 1 | 1 | --
1. Door Ajar Indicator Malfunction

### Circuit/System Description

The body control module (BCM) receives a discrete input from ajar switches within driver and passenger door latches. 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 ajar icon 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 engine has been started and the gear selector is moved from the P (park) position.

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 removing the ground to the BCM. The BCM sends a signal to the IPC to illuminate the door ajar indicator when a door is open.

### Conditions for Running the DTC

The system voltage is 9-16 volts.

### Conditions for Setting the DTC

The BCM detects a short to ground in a passenger door ajar circuit for greater than 10 minutes.

### Action Taken When the DTC Sets

The door ajar indicator is on at all times.

### 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 become 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

Door Ajar Indicator 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, observe the scan tool Passenger Door Ajar Switch. parameter while opening and closing the passenger door. The parameter should change between Door Closed and Door Ajar.

### Circuit/System Testing

1. Ignition OFF, disconnect harness connector at the passenger door latch.
2. Ignition ON, verify the scan tool Passenger Door Ajar Switch parameter is Door Closed.

⇒ | If not the specified value, test the signal circuit terminal 1 for a short to ground. If the circuit tests normal, replace the BCM.

3. If all circuit tests normal, test or replace the passenger door latch.

### Component Testing

1. Ignition OFF, disconnect the harness connector at the passenger door latch.
2. With the switch in the open position, test for infinite resistance between the signal terminal 1 and the ground terminal 3.

⇒ | If not the specified value, replace the passenger door latch.

3. With the switch in the closed position, test for less than 2 ohms between the signal terminal 1 and the ground terminal 3.

⇒ | If greater than the specified range, replace the passenger door latch.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• | Front Side Door Latch Replacement

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