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

Driver Door Ajar Switch Signal

1

2

2

--

Left Rear Door Ajar Switch Signal

1

2

2

--

Passenger Door Ajar Switch Signal

1

2

2

--

Right Rear Door Ajar Switch Signal

1

2

2

--

Driver Door Latch Low Reference

--

2

--

--

Passenger Door Latch Low Reference

--

2

--

--

Left Rear Door Latch Ground

--

2

--

--

Right Rear Door Latch Ground

--

2

--

--

1. Ajar Indicator Always Illuminated

2. Ajar Indicator Inoperative

Circuit/System Description

The driver door switch (DDS) and the passenger door switch (PDS) receive a discrete input from the driver door ajar switch and the passenger door ajar switch respectively. Likewise, the body control module (BCM) receives a discrete input from both the left and right rear door ajar switches. 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 instrument panel cluster (IPC) receives a serial data message from the BCM, DDS, or PDS indicating the door ajar status and the driver information center (DIC) located at the bottom of the IPC, illuminates the appropriate door ajar message when one of the doors is open. If this message is displayed and the vehicle speed is greater than 8 km/h (5 mph), a chime will sound.

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 while opening and closing the driver door. The parameter should change between Active and Inactive.
  2. If the parameter does not change, refer to Driver Door Ajar Switch Malfunction
  3. Observe the scan tool Passenger Door Ajar Sw. parameter while opening and closing the front passenger door. The parameter should change between Active and Inactive.
  4. If the parameter does not change, refer to Passenger Door Ajar Switch Malfunction.
  5. Observe the scan tool Left Rear Door Ajar Sw. and Right Rear Door Ajar Sw. parameters while opening and closing the left and right rear doors. The parameters should change between Door Closed and Door Ajar.
  6. If the parameter does not change, refer to Rear Door Ajar Switch Malfunction.

Circuit/System Testing

Driver Door Ajar Switch Malfunction

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

Passenger Door Ajar Switch Malfunction

  1. Ignition OFF, disconnect the harness connector at the passenger door latch.
  2. Test for less than 20 ohms between the low reference circuit terminal 3 and ground.
  3. If greater than the specified range, test the low reference circuit for an open/high resistance.
  4. Ignition ON, verify the scan tool Passenger Door Ajar Sw parameter is Inactive.
  5. If not the specified value, test the signal circuit terminal 1 for a short to ground. If the circuit tests normal, replace the PDS.
  6. Install a 3A fused jumper wire between the signal circuit terminal 1 and ground. Verify the scan tool Passenger Door Ajar Sw parameter is Active.
  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 PDS.
  8. If all circuits test normal, test or replace the passenger door latch.

Rear Door Ajar Switch Malfunction

  1. Ignition OFF, disconnect the harness connector at the appropriate rear door latch.
  2. Test for less than 10 ohms between the ground circuit terminal listed below and ground:
  3. • Left rear door latch ground circuit terminal 6
    • Right rear door latch ground circuit terminal 3
    If greater than the specified range, test the ground circuit for an open/high resistance.
  4. Ignition ON, verify the appropriate scan tool Rear Door Ajar Sw parameter is 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.
    • Left rear door ajar switch signal circuit terminal 4
    • Right rear door ajar switch signal circuit terminal 1
  6. Install a 3A fused jumper wire between the signal circuit terminal listed below and ground. Verify the scan tool Rear Door Ajar Sw parameter is Door Ajar.
  7. • Left rear door ajar switch signal circuit terminal 4
    • Right rear door ajar switch 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 rear door latch.

Component Testing

  1. Ignition OFF, disconnect the harness connector at the appropriate door latch.
  2. With the switch in the open position, test for infinite resistance between the signal and the ground terminals listed below:
  3. • Driver door latch signal terminal 6 and low reference terminal 8
    • Left rear door latch signal terminal 4 and ground terminal 6
    • Right rear door latch signal terminal 1 and ground terminal 3
    • Passenger door latch signal terminal 1 and low reference terminal 3
    If not the specified value, replace the door latch.
  4. With the switch in the closed position, test for less than 1 ohm between the signal and the ground terminals listed below:
  5. • Driver door latch signal terminal 6 and low reference terminal 8
    • Left rear door latch signal terminal 4 and ground terminal 6
    • Right rear door latch signal terminal 1 and ground terminal 3
    • Passenger door latch signal terminal 1 and low reference terminal 3
    If greater than the specified range, replace the door latch.

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 the IPC, DDS, PDS, or BCM replacement, setup, and programming.