GM Service Manual Online
For 1990-2009 cars only

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 Switch Signal

1

2

2

--

Door Jamb Switch Ground

--

2

2

--

1. Door Ajar Indicator Always Illuminated

2. Door Ajar Indicator Inoperative

Circuit/System Description

The body control module (BCM) provides voltage to each door jamb switch via the door ajar switch signal circuit. The door ajar switches are normally open when the door is fully closed. When a door is opened, the door ajar switch contacts close providing a path to ground. The driver information center (DIC) displays DOORS when the BCM detects that one of the doors are open. The instrument panel cluster (IPC) receives a serial data message from the BCM indicating the door ajar status.

Reference Information

Schematic Reference

Interior Lights 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

  1. Ignition ON, observe the scan tool Driver Door Ajar Sw parameter and while opening and closing the driver door. The parameter should change between Door Closed and Door Ajar.
  2. If the parameter does not change, refer to Driver Door Ajar Malfunction.
  3. With the passenger doors closed, observe the scan tool Passenger Door Ajar Sw parameter while opening and closing each door. The parameter should change between Door Closed and Door Ajar.
  4. If the parameter does not change, refer to Passenger Door/Liftgate Ajar Malfunction.

Circuit/System Testing

Driver Door Ajar Malfunction

  1. Ignition OFF, disconnect the harness connector at the driver door jamb switch.
  2. Test for less than 1 ohm between the ground circuit terminal 2 and ground.
  3. If greater than the specified range, test the ground circuit for an open/high resistance.
  4. Ignition ON, verify the scan tool Driver Door Ajar Sw parameter is Door Closed.
  5. If not the specified value, test the signal circuit terminal 1 for a short to ground. If the circuit tests normal, replace the BCM.
  6. Install a 3A fused jumper wire between the signal circuit terminal 1 and the ground circuit terminal 2. Verify the scan tool Driver Door Ajar Sw parameter is Door Ajar.
  7. If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the BCM.
  8. If all circuits test normal, test or replace the driver door jamb switch.

Passenger Door/Access Panel Ajar Malfunction

  1. Ignition OFF, disconnect the harness connector at the appropriate door jamb switch.
  2. Test for less than 10 ohms between the ground circuit terminal 2 and ground.
  3. If greater than the specified range, test the ground circuit for an open/high resistance.
  4. Ignition ON, verify the scan tool Passenger Door Ajar Sw parameter is Door Closed.
  5. If not the specified value, test the signal circuit terminal 1 for a short to ground. If the circuit tests normal, replace the BCM.
  6. Install a 3A fused jumper wire between the signal circuit terminal 1 and the ground circuit terminal 2. Verify the scan tool Passenger Door Ajar Sw parameter is Door Ajar.
  7. If not the specified parameter, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the BCM.
  8. If all circuits test normal, test or replace the door jamb switch.

Component Testing

  1. Ignition OFF, disconnect the harness connector at the appropriate door jamb switch.
  2. Test for infinite resistance between the signal terminal 1 and the ground terminal 2 with the door jamb switch in the open position.
  3. If not the specified value, replace the door jamb switch.
  4. Test for less than 2 ohms between the signal terminal 1 and the ground terminal 2 with the door jamb switch in the closed position.
  5. If greater than the specified range, replace the door jamb switch.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Door Jamb Switch Replacement
    •  Control Module References for BCM replacement, setup, and programming