Skip the auto shop - Our mechanics make house calls

P0929 OBD-II Trouble Code: Gear Shift Lock Solenoid Circuit Range/Performance

diagnostic check engine light

P0929 code definition

The P0929 code is a generic powertrain code related to the transmission, including pressure faults and sensor failures. In this case, the transmission control module has detected a fault with the gear shift lock solenoid circuit.

What the P0929 code means

A vehicle with an automatic transmission uses the gear shift lock solenoid to ensure that your vehicle cannot be shifted out of “Park” without the brake pedal being depressed. When the vehicle engine is “on” and the brake pedal is fully depressed, the gear shift lock solenoid allows the vehicle to shift from “Park” to “Reverse” or “Drive.”

When the engine control module (ECM) detects an abnormal voltage reading or signal from the gear shift lock solenoid, a code P0929 can be stored.

What causes the P0929 code?

Several problems may cause a P0929 code including:

What are the symptoms of the P0929 code?

Symptoms of a P0929 code may include:

How does a mechanic diagnose the P0929 code?

A mechanic may use several methods to diagnose a P0929 trouble code, including:

  • Utilize an OBD-II scanner to check for a stored P0929 trouble code
  • Check transmission fluid level
  • Check transmission fluid quality
  • If transmission fluid is dirty, check transmission pan for signs of clutch debris or other contaminants
  • Check battery voltage/charge
  • Visually inspect the wiring and electrical system for any obvious signs or damage or wear
  • Check for any blown fuses
  • Test gear shift lock solenoid for continuity
  • Test brake light switch for continuity

Common mistakes when diagnosing the P0929 code

One common cause of a P0929 trouble code is a faulty brake light switch, which will not allow the vehicle to move out of park. The fuse that controls the brake light switch and shift lock may have blown, and should be diagnosed before performing further repairs or replacements.

How serious is the P0929 code?

Because a vehicle’s safe driving operation most likely will be impacted due to faults that store a P0929 code, this code is considered a potentially serious code. When this code appears, it is recommended to immediately take your vehicle to your local service center or mechanic for repair and diagnosis.

What repairs can fix the P0929 code?

Several repairs can fix a P0929 trouble code and include:

Additional comments related to a P0929 code

Note, an automatic transmission will have a “shift lock” feature, which can allow the drive to temporarily bypass a locked gear shift solenoid, and allow you to shift into drive to move your vehicle to a mechanic or out of a potentially dangerous location.

Need help with a P0929 code?

YourMechanic offers certified mobile mechanics who will come to your home or office to diagnose and repair your vehicle. Get a quote and book an appointment online or speak to a service advisor at 1-800-701-6230.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
Icon-warranty_badge-02

Skip the repair shop, our top-rated mechanics come to you.

At your home or office

Choose from 600+ repair, maintenance & diagnostic services. Our top-rated mechanics bring all parts & tools to your location.

Fair & transparent pricing

See labor & parts costs upfront, so you can book with confidence.

12-month, 12,000-mile warranty

Our services are backed by a 12-month, 12,000-mile warranty for your peace of mind.

Get A Quote

Need Help With Your Car?

Our certified mobile mechanics make house calls in over 2,000 U.S. cities. Fast, free online quotes for your car repair.

GET A QUOTE

More related articles

P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
How to Transfer a Car Title in Idaho
In order to prove ownership of a car, you must have the title. However, when a car is sold, given away or inherited, the title needs...
Veteran and Military Driver Laws and Benefits in Idaho
The state of Idaho offers a number of benefits and perks for those Americans who have either served in an Armed Forces branch in the...


Related questions

Q: Does the VIN number have to be in the ECM for the vehicle to run?

Some new ECMs will give you a certain amount of free starts before it will not start unless the VIN is added. I am not sure if this is the case with your ECM but you have a dealer telling...

Q: OBD-II scanner read code P0108

Hello. The MAP sensor reading on a scanner should read about 1.0 to 1.5 volts at idle and 4.5 to 4.8 volts at wide open throttle. The MAP should read 4.8 volts or more when you have the key on...

Q: My car has trouble code P0745, do I need to replace the solenoid?

Diagnostic Trouble Code P0745 refers to out of range voltage at a solenoid-operated valve that regulates hydraulic pressure in the transmission based on outputs from the Transmission Control Module (TCM). Code P0745 is set when the TCM sees an out...