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 Lock Actuator - Driver - Lock Control | 1 | 1 | 1 | --
Door Lock Actuator - Passenger - Lock Control | 1 | 1 | 1 | --
Door Lock Actuator - Driver - Unlock Control | 1 | 1 | 1 | --
Door Lock Actuator - Passenger - Unlock Control | 1 | 1 | 1 | --
Driver Door Jamb Switch Signal | 2 | 2 | 2 | --
Passenger Door Jamb Switch Signal | 2 | 2 | 2 | --
Remote Control Door Lock Receiver (RCDLR) Voltage Supply | 3 | 3 | 3 | --
Remote Control Door Lock Receiver (RCDLR) Serial Data | B3100 02 | B3100 02 | B3100 01 | B3100 73
Driver Door Latch Ground | -- | 2 | 2 | --
Passenger Door Latch Ground | -- | 2 | 2 | --
Remote Control Door Lock Receiver (RCDLR) Ground | -- | 3 | 3 | --
1. Power Door Locks Inoperative 2. Door Ajar Indicator Malfunction 3. Keyless Entry System Inoperative

### Circuit/System Description

The body control module (BCM) provides voltage to each door latch assembly over the door jamb switch signal circuits. The door latch assemblies are permanently grounded at G201. The door ajar switches are normally open when the doors are fully closed. When a door is opened, the door ajar switch contacts close providing a path to ground. The driver information center (DIC) located at the bottom of the instrument panel cluster (IPC), illuminates the DOOR AJAR indicator when the BCM detects that one of the doors is open. The IPC receives a GMLAN serial data message from the BCM indicating the door ajar status. If this message is displayed and the vehicle speed is greater than 4.8 km/h (3 mph), a chime will sound.

### Reference Information

#### Schematic Reference

Instrument Cluster Schematics

#### Connector End View Reference

Displays and Gages Connector End Views

#### Electrical Information Reference

• | Circuit Testing

• | Connector Repairs

• | Testing for Intermittent Conditions and Poor Connections

• | Wiring Repairs

#### Scan Tool Reference

• | Scan Tool Output Controls

• | Scan Tool Data List

• | Scan Tool Data Definitions

### Circuit/System Testing

#### Door Ajar Indicator Always On

1. Ignition ON, close all doors.
2. Install a scan tool and observe the Door Ajar Switch parameters for both doors in the BCM data list. The scan tool should display Door Closed for both doors.

⇒ | If the scan tool displays Door Closed for both Door Ajar Switch parameters, replace the IPC.

3. Disconnect the appropriate door latch assembly harness connector and observe the door ajar indicator. The door ajar indicator should turn off.

⇒ | If the door ajar indicator remains illuminated, repair the appropriate door jamb switch signal circuit for a short to ground. If the circuit tests normal, replace the BCM.

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

#### Door Ajar Indicator Inoperative

1. Ignition ON, open all doors.
2. Install a scan tool and observe the Door Ajar Switch parameters for both doors in the BCM data list. The scan tool should display Door Ajar for both doors.

⇒ | If the scan tool displays Door Ajar for both Door Ajar Switch parameters, replace the IPC.

3. Ignition OFF, disconnect the appropriate door latch harness connector.
4. Install a 3-amp fused jumper between the door jamb switch signal circuit and ground at the door latch harness connector.
5. Ignition ON, observe the door ajar indicator. The door ajar indictor should illuminate.

⇒ | If the door ajar indicator does not illuminate, repair the appropriate door jamb switch signal circuit for a short to voltage or an open/high resistance. If the circuits test normal, replace the BCM.

6. Ignition OFF, install a 3-amp fused jumper between the door jamb switch signal circuit and the door latch assembly ground circuit at the door latch harness connector.
7. Ignition ON, observe the door ajar indicator. The door ajar indictor should illuminate.

⇒ | If the door ajar indicator does not illuminate, repair the appropriate door latch ground circuit for an open/high resistance.

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

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• | Front Side Door Lock Replacement

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