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Transmission Control Lever Malfunction (Column)




Transmission Control Lever Malfunction (Column)

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.

Diagnostic Fault Information





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 body control module (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.

Reference Information
Schematic Reference

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

Component Connector End Views (Connector Views)
Description and Operation

* Automatic Transmission Shift Lock Control Description and Operation (Column Shift) (Automatic Transmission Shift Lock Control Description and Operation (Column Shift))Automatic Transmission Shift Lock Control Description and Operation (Floor Shift) (Automatic Transmission Shift Lock Control Description and Operation (Floor Shift))
* Reverse Lockout System Description and Operation (Reverse Lockout System 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

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 Malfunction (Stop Lamps Malfunction).

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 shift lock control solenoid.
2. Ignition OFF, test for less than 1.0 ohm between the ground circuit terminal A 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 A and the control circuit terminal B.
4. Ignition ON, command the scan tool BCM Brake To Shift Control output control ON and OFF. 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 (Verification Tests) after completing the diagnostic procedure.

* Automatic Transmission Shift Lock Control Actuator Replacement (Column Shift) (Service and Repair)
* Control Module References (Programming and Relearning) for BCM replacement, setup, and programming