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

Left Front Door Ajar Switch Signal

1

1

1

--

Right Front Door Ajar Switch Signal

1

1

1

--

Driver Door Lock Actuator Ground

--

1

--

--

Passenger Door Lock Actuator Ground

--

1

--

--

1. Door Ajar Indicator Malfunction

Circuit/System Description

The body control module (BCM) receives a discrete input from the driver and passenger door ajar switch signal circuits. The door ajar switches are integral to each door lock actuator assembly. When a door is opened, the normally open door ajar switch closes. With the door ajar switch closed, ground is provided to the door ajar switch signal circuit. The BCM interprets this and sends a serial data message to the instrument panel cluster (IPC). When a door is open/ajar and the vehicle is in any gear other than PARK, the driver information center (DIC) will display DOOR AJAR for the appropriate door that is opened. If the door is still ajar and the vehicles speed is greater than 5 km/h (3 mph) a chime will sound.

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 Driver Door Ajar Sw. and Door Ajar Switch parameters and the DOOR AJAR indicator on the DIC while opening and closing the driver door and passenger door. The parameter should change between Door Closed and Door Ajar and the DOOR AJAR indicator should turn ON and OFF.

If the parameter changes but the DOOR AJAR indicator is always ON or always OFF, replace the IPC.

Circuit/System Testing

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

Component Testing

  1. Ignition OFF, disconnect the harness connector at the appropriate door lock actuator.
  2. Test for infinite resistance between the signal terminal and the ground terminal listed below with the switch in the open position.
  3. • Driver door lock actuator signal terminal 4 and ground terminal 6
    • Passenger door lock actuator signal terminal 1 and ground terminal 3
    If not the specified value, replace the door lock actuator.
  4. Test for less than 2 ohms between the signal terminal and the ground terminal listed below with the switch in the closed position.
  5. • Driver door lock actuator signal terminal 4 and ground terminal 6
    • Passenger door lock actuator signal terminal 1 and ground terminal 3
    If greater than the specified range, replace the door lock actuator.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Front Side Door Lock Replacement
    •  Control Module References for BCM or IPC replacement, setup and programming