Skip the auto shop - Our mechanics make house calls

P0502 OBD-II Trouble Code: Vehicle Speed Sensor Low Input

Check Engine Light

Vehicle Speed Sensor Low Input

What the P0502 code means

The P0502 trouble code means that the Engine Control Module (ECM) has detected a different reading of speed between the vehicle speed sensor and the wheel speed sensors.

What are the causes of the P0502 code?

  • A faulty vehicle speed sensor
  • Damaged wiring or connectors in the vehicle speed sensor circuit
  • Multiple faulty wheel speed sensors/ hub bearings
  • Broken ABS tone rings
  • A faulty powertrain control module
  • Incorrect size wheels or tires
  • A faulty instrument cluster

What are the symptoms of the P0502 code?

Other than a Check Engine Light and an inaccurate speedometer, there should be next to no symptoms associated with this trouble code.

How does a mechanic diagnose the P0502 code?

The most common cause of the P0502 trouble code is a faulty vehicle speed sensor so the mechanic would likely start by locating it. If the sensors wiring and connector seem to be in good condition, the mechanic would then test the vehicle speed sensor using the manufacturer’s recommended procedure.

The mechanic would also check all the wheels and tires to ensure they are the correct size. A check of the suspension on all four wheels would be performed to check the tone rings and wheel speed sensors.

Finally, if no other issues are found, the ECM would be tested and parts would be replaced at the customer’s request.

Common mistakes when diagnosing the P0502 code

A common mistake that could be made when this trouble code is stored would be to replace the vehicle’s instrument cluster due to the inaccurate speedometer. The instrument cluster receives a signal from the vehicle speed sensor so it is important to check there first.

How serious is the P0502 code?

This trouble code is not very serious at all due to the fact that it does not cause any drivability issues. The only thing to worry about with this trouble code is getting a speeding ticket due to the inaccurate speedometer.

What repairs can fix the P0502 code?

Repairs that can fix the P0502 trouble code may include:

Additional comments regarding the P0502 code?

Many people like the looks of very large wheels on their vehicle. However, they do not realize the potential damages this can cause to the vehicle. The ride quality suffers, the wheels are more susceptible to damage from pot-holes, the brakes do not work as well, the steering is not as predictable, and codes such as the P0502 may be stored.

Need help with a P0502 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

How Long Does a Throttle Return Spring Last?
Not all vehicles on the road feature an electronic throttle control (ETC), which is also called drive-by-wire. For vehicles that don't offer this system, they have a throttle cable instead that...
P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the P0052 code means This code is seen when the Engine Control Module (ECM) tries to control the...
Insurance Requirements for Car Registration in Kentucky
The Kentucky Transportation Cabinet requires that all drivers in Kentucky carry liability automotive insurance, or “financial responsibility” in order to operate a vehicle legally and maintain vehicle...


Related questions

Q: p0720 code will not stay gone

Hello. If the vehicle speed sensor has been replaced then the wiring to the sensor must be tested. If there is high resistance or any breaks in the wire then this will occur. I have also seen the signal gear...

Q: Check Engine not working

Hello. There is a chance that the bulb for the Check Engine Light has burned out. When you turn the key to the run position, a mechanic would conduct a bulb test to see if this will illuminate the Check...

Q: i need to know the key sequence to get the check engine codes

Hello. The old style of retrieving codes was indeed done by turning the key on and off again. However vehiles manufactured after 1996 are equipped with OBD-II diagnostic systems. This means the driver or technician can acess and even control...