B2991

DTC B2991

Diagnostic Instructions

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



DTC Descriptor
DTC B2991 00
- Passenger Door Ajar Circuit




Diagnostic Fault Information






Circuit/System Description

The body control module (BCM) receives a discrete input from ajar switches within driver and passenger door latches. 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 ajar icon in the driver information center (DIC) and also send a serial data massage to the radio to activate the door ajar audible warning when the engine has been started and the gear selector is moved from the P (park) position.


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 illuminate the door ajar indicator when a door is open.


Conditions for Running the DTC

The system voltage is 9-16 volts.


Conditions for Setting the DTC

The BCM detects a short to ground in a passenger door ajar circuit for greater than 10 minutes.


Action Taken When the DTC Sets

The door 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.



Reference Information
Schematic Reference

Interior Lights Schematics (Interior Lights Schematics)
Connector End View Reference

Component Connector End Views (Connector Views)
Description and Operation

Door Ajar Indicator Description and Operation (Description and Operation)
Electrical Information Reference

* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)

Scan Tool Reference

Control Module References (Programming and Relearning) for scan tool information


Circuit/System Verification

Ignition ON, with all doors closed, observe the scan tool Passenger Door Ajar Sw. parameter while opening and closing the passenger and rear doors. The parameter should change between Door Closed and Door Ajar.


Circuit/System Testing

1. Ignition OFF, disconnect harness connector at the appropriate passenger or rear door latch.
2. Ignition ON, verify the scan tool Passenger Door Ajar Sw parameter is Door Closed.

• 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.


* Passenger door latch signal circuit terminal 1
* Left rear door latch signal circuit terminal 4
* Right rear door latch signal circuit terminal 1

3. If all circuit tests normal, test or replace the 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 terminal and the ground terminal listed below:

* Passenger door latch signal terminal 1 and ground terminal 3
* Right rear door latch signal terminal 1 and ground terminal 3
* Left rear door latch signal terminal 4 and ground terminal 6


• If not the specified value, replace the door latch.

3. With the switch in the closed position, test for less than 2 ohms between the signal and the ground terminals listed below:

* Passenger door latch signal terminal 1 and ground terminal 3
* Right rear door latch signal terminal 1 and ground terminal 3
* Left rear door latch signal terminal 4 and ground terminal 6


• If not the specified value, replace the door latch.




Repair Instructions

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

* Front Side Door Latch Replacement (Service and Repair)
* Rear Side Door Latch Replacement (Service and Repair)
* Control Module References (Programming and Relearning) for BCM replacement, setup and programming