B2976

DTC B2976

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Initial Inspection and Diagnostic Overview
* Review Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC B2976 00
- Driver Door Ajar Circuit

Diagnostic Fault Information






Circuit/System Description

The body control module (BCM) receives a discrete input from each of the 4 jamb switches to indicate the status for each door. 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 appropriate ajar message in the driver information center (DIC) and also send a serial data massage to the radio to activate the door ajar audible warming when the transmission is removed from PARK and the vehicle speed is greater then 8 km/h (5 mph).

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 turn on the door ajar light when a door is open.

Conditions for Running the DTC

The system voltage is 9-18 volts.

Conditions for Setting the DTC

The BCM detects a short to ground in the driver door ajar circuit for longer than 10 minutes.

Action Taken When the DTC Sets

The 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.

Circuit/System Verification

Ignition ON, observe the scan tool Driver Door Ajar Sw parameter while opening and closing the driver door. The reading should change between Door Closed and Door Ajar.

Circuit/System Testing

1. Ignition OFF, disconnect harness connector at the driver door lock.
2. Ignition ON, verify the scan tool Driver Door Ajar Sw parameter is Door Closed.

^ If not the specified value, test the signal circuit for a short to ground. If the circuit tests normal, replace the BCM.

3. If all circuits test normal, test or replace driver door lock.

Component Testing

1. Ignition OFF, disconnect the harness connector at the driver door lock.
2. With the switch in the open position, test for infinite resistance between the signal terminal and the ground terminal listed below:

* Driver door lock signal terminal 6 and ground terminal 8 (Uplevel).
* Driver door lock signal terminal 4 and ground terminal 6 (Base).

^ If not the specified value, replace the appropriate door lock.

3. With the switch in the closed position, test for less than 1.0 ohm between the signal terminal and the ground terminal listed below:

* Driver door lock signal terminal 6 and ground terminal 8 (Uplevel).
* Driver door lock signal terminal 4 and ground terminal 6 (Base).

^ If greater than the specified range, replace the driver door lock.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure. Verification Tests

* Front Side Door Lock Replacement (Impala).