Transmission Control Lever Malfunction

Transmission Control Lever Malfunction

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 body control module (BCM) controls the shift lock solenoid by providing battery voltage to the shift lock control solenoid. The BCM utilizes a smart driver to control the voltage supplied to the shift lock solenoid. The smart driver monitors the voltage and current flow of the control circuit.

Reference Information
Schematic Reference

* Shift Lock Control Schematics ([1][2]Electrical Diagrams)
* Inline Harness Connector End Views ([1][2]Diagrams)

Connector End View Reference

Component Connector End Views (Connector Views)
Description and Operation

Automatic Transmission Shift Lock Control Description and Operation (LS4/5.3L) (Description and Operation)Automatic Transmission Shift Lock Control Description and Operation (L26/L32/3.6L) (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, with the brake pedal applied, observe the scan tool Brake Applied Output Signal parameter. The reading should be ON with the brake pedal depressed.

• If not the specified parameter, 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 automatic transmission shift lock actuator.
2. Ignition OFF, test for less than 1.0 ohm between the ground circuit terminal B (column shift) or terminal F (floor shift) and ground.

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

3. Connect a test lamp between the control circuit terminal A (column shift) or terminal E (floor shift) and ground.
4. Ignition ON, command the scan tool BCM BTSI solenoid command 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 a short to voltage. If the circuit tests normal, replace the BCM.
• If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.

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

Repair Instructions

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

* Transmission Control Replacement (4T65-E - Automatic Transmission)
* Control Module References (Programming and Relearning) for BCM replacement, setup, and programming