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. |
Diagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
Shift Lock Control Solenoid Control | -- | 1 | 2 | -- |
Shift Lock Control Solenoid Ground | -- | 1 | -- | -- |
1. Shift lever will move from PARK without pressing on the brake pedal 2. Shift lever will not move from PARK with the brake pedal pressed | ||||
Circuit/System Description
The body control module (BCM) controls the shift lock solenoid by removing battery voltage from 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.
Diagnostic Aids
| • | Use a scan tool to verify there are no brake pedal position sensor and/or transmission internal mode switch (IMS) DTCs set that could cause the BCM not to provide battery voltage to the A/T shift lock solenoid. |
| • | If the automatic transmission shift lock control circuit is shorted to battery positive voltage, the A/T shift lock solenoid will be energized. The shift lever will not move out of the PARK position without depressing the brake pedal. |
Reference Information
Schematic Reference
Connector End View Reference
Description and Operation
Automatic Transmission Shift Lock Control Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Verification
- Ignition ON, observe the scan tool Shift Lock Solenoid Command parameter. The reading should change from LOCK to UNLOCK when the brake pedal is depressed.
- Press the brake pedal several times, the vehicle operator should be able to move the shifter lever out of the park position.
Circuit/System Testing
- Ignition OFF, disconnect the harness connector at the automatic transmission shift lock actuator.
- Ignition OFF, test for less than 1 ohm between the ground circuit terminal G and ground.
- Connect a test lamp between the control circuit terminal E and ground.
- Ignition ON, command the Shift Lock Solenoid command to Lock and Unlock, with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states.
- If all circuits test normal, test or replace the shift lock control solenoid.
| ⇒ | If greater than the specified range, test the ground circuit for an open/high resistance. |
| ⇒ | If the test lamp is always ON, test the control circuit for a short to voltage. If all circuits test normal, test or 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 all circuits test normal, test or replace the BCM. |
Component Testing
- Install a 10A fused jumper wire between the control circuit terminal E and 12 volts. Install a jumper wire between the ground circuit terminal G and ground.
- Listen for the solenoid to turn ON and OFF.
| ⇒ | If the function does not perform as specified, 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 |
