B2705

DTC B2705

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.



DTC Descriptors
DTC B2705 02
- Gearshift Unlock Circuit Short to Ground

DTC B2705 05
- Gearshift Unlock Circuit Short to Battery or Open




Diagnostic Fault Information






Circuit/System Description

The body control module (BCM) controls the automatic transmission shift lock control solenoid by removing battery positive voltage from the solenoid. The BCM utilizes a smart driver to control the voltage supply circuit to the automatic transmission shift lock control solenoid. The smart driver monitors the voltage and current flow of the control circuit.


Conditions for Running the DTC

* Ignition ON.
* The brake pedal is pressed.
* The transmission is in the PARK position.



Conditions for Setting the DTC

* DTC B2705 02 sets if the automatic transmission shift lock control solenoid control circuit is shorted to ground.
* DTC B2705 05 sets if the automatic transmission shift lock control solenoid control circuit is open or shorted to voltage.
* DTC B2705 05 sets if the ground circuit is open.



Action Taken When the DTC Sets

The BCM will not attempt to enable the voltage supply circuit of the automatic transmission shift lock control solenoid until the next key cycle.


Conditions for Clearing the DTC

* A current DTC will clear when the malfunction is no longer present and the ignition switch is cycled.
* All BCM history codes will clear after 100 ignition cycles with no current codes active during the 100 ignition cycles.



Reference Information
Schematic Reference

Shift Lock Control Schematics ([1][2]Electrical Diagrams)
Connector End View Reference

Component Connector End Views
Description and Operation

Automatic Transmission Shift Lock Control Description and Operation (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, command the A/T shift lock control solenoid lock and unlock with the scan tool. The gearshift lever should be unlocked when ON and locked in PARK when OFF.


Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the shift lock control solenoid.
2. Ignition OFF, test for less than 1.0 ohm between the ground circuit terminal G and ground.

• If greater than the specified range, test the ground circuit for an open/high resistance.

3. Install a test lamp between the ground circuit terminal G and the control circuit terminal E.
4. Ignition ON, command the scan tool BCM Brake To Shift Control output control lock and unlock. The test lamp should turn ON and OFF as commanded.

• If the test lamp is always ON, test the control circuit for short to voltage. If the circuit tests normal, replace the BCM.
• If the test lamp is always OFF, test the control circuit for short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.

5. If the circuit tests normal, test or replace the shift lock control solenoid.



Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.


Control Module References for BCM replacement, setup, and programming