Skip the auto shop - Our mechanics make house calls

Symptoms of a Bad or Failing Speedometer Sensor

speedometer sensor

Bad or Failing Speedometer Sensor Inspection

by a top-rated mechanic at your home or office

The electronics in today's cars and trucks are extremely complex. However, one of the simplest devices we rely on to deliver us factual data is the speedometer. Essentially, the speedometer is powered by three independent components; the speedometer on the dashboard, the cable attached from the speedometer to the driveshaft and the speedometer sensors attached to the driveshaft to measure speed. Some speedometer issues are due to dirty or faulty sensors that relay false data through the cable and eventually show up on the dashboard.

HAVE SYMPTOMS OF CAR TROUBLE?
Get an $80 diagnostic
by a top-rated mechanic at your home or office.

Get a quote · Book an Appointment · Our expert mechanics come to you.

Where is the speedometer sensor located?

The speedometer sensor is located in the transmission of your vehicle and is designed to register the driveshaft’s rotational speed. The sensor delivers this information through the speedometer cable and to the vehicle’s computer, which converts electrical pulses into a numerical speed. Eventually that number is displayed on the speedometer and tells you precisely how fast you are driving. If the speedometer sensor is not working properly, the speedometer will be inaccurate; potentially leading to speeding tickets or unsafe driving situations.

The symptoms noted below will give you an indication that a problem exists with your speedometer sensor:

1. Speedometer does not work

Whether you have a digital or manual speedometer, if it's not displaying accurate information, it doesn't really help you. One of the biggest signs your speedometer sensor is not working properly is the speedometer will display inaccurate readings or the needle or digital numbers will not move at all on the speedometer display. A malfunctioning speedometer sensor can also cause a speedometer to act erratically, fluctuating the reading from one speed to another; even though in reality you're not speeding up or slowing down.

If you feel you are driving faster or slower than what the speedometer reads, it is a good idea to have your vehicle inspected by Your Mechanic, as this might be a problem with the sensor that can be repaired or an indication that the speedometer sensor needs replacement. Being proactive about repairing your speedometer issue can improve safety, not only for you, but others on the road. It can also reduce the potential of getting two citations; one for speeding and another for a damaged speedometer.

HAVE SYMPTOMS OF CAR TROUBLE?
Get your car fixed at your home or office.

Get a quote · Book an Appointment · Our expert mechanics come to you.

2. Cruise control does not work

The speedometer sensor is also a critical component in the proper operation of a vehicle’s cruise control. When the sensor is not working correctly, it will not send a signal to the CPU, which impacts the vehicle’s ability to set the throttle for a desired speed. As a safety measure, automotive manufacturers engineer the cruise control in a way that if the speedometer sensor is acting up, it won't engage the cruise control at all. On most cars sold today, this will be indicated by the cruise control light being illuminated on the dashboard - even if it's not engaged. If you experience this problem, it's possible that the speedometer sensor needs to be replaced.

3. Check Engine Light comes on

The speedometer sensor is located inside the transmission and attached to a driveshaft, which impacts multiple functions of the car. Due to this fact, it's possible that the Check Engine Light will light up on the dashboard if a sensor problem is discovered by the vehicle's CPU. Regardless of why the check engine light is illuminated, it's never a good thing, nor should it be avoided. If the check engine light shows up anytime, contact a mechanic as soon as possible so they can diagnose the problem with the correct diagnostic tools. Sometimes the issue is small and the CPU needs to be reset; but don't take that risk.

4. Vehicle loses power

Today's cars and trucks have electronic fuel injection, which is controlled by the onboard computer. The EFI supplies fuel to the engine based on input from multiple sensors; one of which is the speedometer sensor. If you notice that your car starts to lose power; especially when you apply pressure to the throttle, this might be caused by a damaged or malfunctioning speedometer sensor. This problem could be potentially harmful to other mechanical components on your vehicle, so don't ignore the issue. Contact a certified mechanic as soon as possible to determine what is causing this issue.

As you can see, the speedometer sensor impacts the operation of multiple components that allows you to efficiently operate your car or truck. Anytime you experience any of the above warning signs, contact a professional mechanic to properly diagnose and repair the issue.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
Still not sure about your car's issue?
Diagnose your car
What kind of issue are you experiencing?
Brakes are squeaking
Car is not starting
Car is overheating
Car is shaking (vibrating)
Fluids are leaking
Heating and A/C
Smoke or steam is coming out of the car
Warning light is on
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

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...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...


Related questions

Q: I have a 2004 Buick Rendevouz that doesn't want to start. At first, it had a hesitation problem and it died at low rp

The camshaft position sensor will make the engine run but poorly. Check the crankshaft position sensor to see if its damaged or unplugged. A damaged crankshaft position sensor will cause a no spark condition. If you need further assistance with...

Q: Transmission quits after 10 miles.

You most likely have a vehicle speed sensor issue or a worn 3-4 clutch that is slipping. Turning off the ignition will reset and cause the computers to begin re-reading the VSS and also reset gear monitoring. The fault codes...

Q: My truck is bucking at different speeds but it smooths out during acceleration.

Hi there. Check the contacts to the engine oil temperature sensor. See if the contacts are loose and if they are falling off. Also, check the wiring to the sensor and see if its over a spark plug wire. Its...