B2500

DTC B2500

Diagnostic Instructions

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

DTC Descriptor
DTC B2500 00
- Driver Exterior Unlock Switch Circuit

Diagnostic Fault Information





Circuit/System Description

The driver window switch monitors the voltage level of the key switch unlock signal circuit. When the key is inserted into the driver door key cylinder and turned to the Unlock position, a switch within the driver door latch closes causing the voltage to drop within the key switch unlock signal circuit. The driver window switch will detect the drop in voltage and will send a serial data message to the BCM commanding all the doors to unlock.

Conditions for Running the DTC

* The ignition is ON.
* The system voltage is 9-16 V.

Conditions for Setting the DTC

The BCM detects a short to ground on the driver door key switch signal circuit.

Action Taken When the DTC Sets

The BCM will ignore the unlock command from the key cylinder switch.

Conditions for Clearing the DTC

* This DTC will be current for as long as the fault is present
* When the fault is no longer present, the DTC will be a history DTC
* A history DTC will clear after 50 ignition cycles

Reference Information
Schematic Reference

Door Lock/Indicator Schematics (Door Lock/Indicator Schematics)
Connector End View Reference

Component Connector End Views (Connector End Views By Name)
Description and Operation

Power Door Locks Description and Operation (Description and Operation)
Electrical Information Reference

* Circuit Testing (Circuit Testing)
* Connector Repairs (Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (Wiring Repairs)

Scan Tool Reference

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

Circuit/System Verification

Insert the key into the driver door lock cylinder, turn the key to the unlock position while observing the scan tool Driver Door Key Cylinder Unlock Switch parameter, the value should change from Inactive to Active.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the A23D door latch assembly-driver.
2. Ignition ON, verify the scan tool Driver Door Key Cylinder Unlock Switch parameter is Inactive.

• If not the specified value, test the signal circuit terminal listed below for a short to ground. If the circuits test normal, replace the S79D window switch - driver.

* Right hand drive terminal 4
* Left hand drive terminal 9

3. If all circuits tests normal, test or replace the A23D door latch assembly-driver.

Component Testing

1. Ignition OFF, disconnect the harness connector at the A23D door latch assembly-driver.
2. Test for infinite resistance between the terminals listed below with the switch in the open position.

* Right hand drive terminal 4 and terminal 8
* Left hand drive terminal 9 and terminal 8

• If not the specified value, replace the A23D door latch assembly-driver.

3. Test for less than 2.0 ohm between the terminals listed below with the switch in the unlock position.

* Right hand drive terminal 4 and terminal 8
* Left hand drive terminal 9 and terminal 8

• If greater than the specified range, replace the A23D door latch assembly-driver.

Repair Instructions

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

* Front Side Door Window and Multifunction Switch Replacement (Front Side Door Window and Multifunction Switch Replacement)
* Front Side Door Lock Replacement (Front Side Door Lock Replacement)