Gear Shift Lock Solenoid Circuit High Voltage
The P0931 code indicates that the Powertrain Control Module (PCM) has detected a high voltage condition in the gear shift lock solenoid/actuator control circuit. This solenoid prevents the shifter from moving out of Park unless the brake pedal is pressed. A high voltage reading suggests a short to power, a faulty solenoid, or a wiring issue. This can prevent the shifter from releasing, making the vehicle unable to shift out of Park.
01. Most Common Causes
- Short to power in the shift lock solenoid circuit
- Faulty shift lock solenoid/actuator
- Damaged wiring or connectors in the circuit
- Faulty brake pedal position switch
- Failed PCM (rare)
02. Symptoms You Will Notice
- Unable to shift out of Park
- Brake pedal feels normal but shifter stuck
- Check Engine Light illuminated
- Shift lock override button may be needed to move shifter
03. Step-by-Step Diagnosis
Step 1: Scan for codes and verify P0931 is present.
Step 2: Check brake pedal switch operation and signal to PCM.
Step 3: Inspect shift lock solenoid wiring for shorts or damage.
Step 4: Test solenoid resistance and voltage supply.
Step 5: Replace solenoid if faulty; repair wiring as needed.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
No, because the shifter may be stuck in Park, preventing the vehicle from being driven. If you can manually override the shift lock, you may drive cautiously to a repair shop, but it's not recommended.
How much does it cost to fix?▼
Typically between $50 and $150 for parts and labor, depending on whether it's a simple wiring repair or solenoid replacement.