Transmission Control Lever Malfunction (Column Shift)

Transmission Control Lever Malfunction (Column Shift)

Diagnostic Fault Information

Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Initial Inspection and Diagnostic Overview

Circuit/System Description

The automatic transmission shift lock control system is a safety device that prevents an inadvertent shift out of PARK when the engine is running. The driver must press the brake pedal before moving the shift lever out of the PARK position. The solenoid is grounded at G300. When the brake pedal is pressed, the BCM sends a voltage signal to the shift lock control solenoid through the shift lock solenoid control circuit. This signal mechanically unlocks the shift lever allowing the driver to move the shift lever out of the PARK position.

Circuit/System Verification

1. Ignition ON, while pressing the brake pedal, observe the scan tool Brake Applied Output Signal parameter. The reading should be ON with the brake pedal pressed.
^ If not the specified value, refer to Stop Lamps Inoperative. Stop Lamps Inoperative

2. Press the brake pedal, the vehicle operator should be able to move the shifter lever out of the park position.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the Automatic Transmission Shift Lever assembly.
2. Ignition OFF, test for less than 1.0 ohm of resistance between the ground circuit terminal B and ground.
^ If greater than the specified range, test the ground circuit for an open/high resistance.

3. While pressing the brake pedal, verify that a test lamp illuminates between the control circuit terminal A and ground.
^ If the test lamp does not illuminate, test the control circuit for a short to ground or an open/high resistance. If all circuits test normal, test or replace the BCM.

4. If all circuits test normal, test or replace the shift lock actuator.

Repair Instructions

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

* Automatic Transmission Shift Lock Actuator Replacement
* Control Module References for BCM replacement, setup and programming.