Gear Shift Lock Solenoid Circuit Range/Performance
The P0929 code indicates that the powertrain control module (PCM) has detected a range or performance issue in the gear shift lock solenoid/actuator control circuit. This solenoid is responsible for locking the gear shift lever in Park when the brake pedal is not pressed, preventing accidental shifting. The PCM monitors the circuit's voltage and resistance; if they fall outside expected parameters, this code is set. Common causes include a faulty solenoid, wiring issues, or a defective brake switch.
01. Most Common Causes
- Faulty gear shift lock solenoid
- Open or shorted wiring in the solenoid circuit
- Defective brake pedal position switch
- Corroded or loose electrical connectors
- Failed PCM (rare)
02. Symptoms You Will Notice
- Gear shift lever stuck in Park
- Unable to shift out of Park without using shift lock override
- Brake lights not working
- Check Engine Light illuminated
03. Step-by-Step Diagnosis
Step 1: Use a scan tool to confirm P0929 and check for related codes (e.g., brake switch codes).
Step 2: Inspect the brake pedal switch for proper operation and adjustment.
Step 3: Test the gear shift lock solenoid by applying 12V directly to see if it clicks.
Step 4: Check wiring and connectors between PCM, brake switch, and solenoid for damage or corrosion.
Step 5: If all else is good, replace the gear shift lock solenoid.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
No, it is not safe. The vehicle may be stuck in Park, preventing you from driving. If you can shift out of Park using the override, you can drive to a repair shop, but the brake shift interlock may not function properly, increasing the risk of unintended movement.
How much does it cost to fix?▼
The cost typically ranges from $50 to $150 for parts and labor. The solenoid itself is inexpensive (around $20-$50), and labor is usually under an hour. However, if wiring repairs or PCM replacement is needed, costs can be higher.