OBD-II Generic Error Code P0931: How to Fix It

Q: Can I still drive my car with a P0931 code?

It depends on the symptoms. If your shift lever is stuck in Park, you obviously cannot drive the vehicle. If the car shifts but the P0931 code is stored, limited driving may be possible but is not recommended — the gear shift lock solenoid is a safety feature designed to prevent unintended movement of the vehicle, and bypassing or ignoring its malfunction could result in a hazardous situation. Address the fault as soon as possible.

Q: What is the gear shift lock solenoid and what does it do?

The gear shift lock solenoid is an electromagnetic safety device built into your vehicle's shift mechanism. Its job is to lock the gear selector in the Park position until you press the brake pedal. When you press the brake, the solenoid receives a signal and retracts a locking pin, allowing the shifter to move. This prevents the car from accidentally being shifted out of Park without the driver's foot on the brake.

Q: What causes the P0931 code to set?

Common causes include a faulty gear shift lock solenoid with internal high resistance, damaged or shorted wiring in the solenoid circuit (particularly a short to power), a defective brake pedal position switch sending incorrect signals, corroded electrical connectors, poor ECM ground connections, or — in rare cases — an internal ECM fault.

Q: How much does it cost to fix a P0931 code at a repair shop?

Repair costs vary by vehicle make and model and local labor rates. The gear shift lock solenoid itself is generally an inexpensive part. Labor to diagnose the fault typically runs 1-2 hours at shop rates. If only the solenoid needs replacement, total repair costs are often moderate. If wiring repair or ECM-related work is needed, costs can increase significantly. Getting a diagnostic estimate from a trusted shop before authorizing repairs is always advisable.

Q: Is P0931 the same as P0930 or P0932?

These codes are related but distinct. P0930 indicates a general circuit malfunction for the gear shift lock solenoid, P0931 specifically indicates a high-voltage condition in that circuit, and P0932 typically indicates a low-voltage condition. Each has different root causes: a high code (P0931) often points to a short to power or a faulty solenoid with high resistance, while a low code (P0932) would suggest an open circuit or short to ground. Always diagnose based on the specific code stored.

Abstract

Error code P0931 is a generic OBD-II trouble code that indicates the vehicle's Engine Control Module (ECM) has detected an abnormally high voltage signal from the gear shift lock solenoid circuit. The gear shift lock solenoid is a safety component that prevents the transmission shift lever from being moved out of Park unless the brake pedal is depressed. When this code appears, your vehicle may be stuck in Park, shift unexpectedly, or behave erratically during gear changes, posing a potential safety risk that should be addressed promptly.