Skip the auto shop - Our mechanics make house calls

Symptoms of a Bad or Failing Wheel Speed Sensor

wheel speed sensor

Drivers across the US would be prone to multiple speeding tickets without the important assistance of the wheel speed sensor. This component, which is also referred to as an ABS sensor, is attached to the hub of a drive tire and is responsible for monitoring multiple vehicle functions such as traction control, anti-lock braking systems, and obviously, the vehicle’s speed. Due to this fact, when the wheel speed sensor is going bad or failing, it will commonly impact the operation of these other vehicle functions and display certain warning signs that any driver can instantly notice as they drive.

The wheel speed sensor is different than the speed sensor attached inside the vehicle's transmission. Its job is to record the actual wheel speed and report this data to the vehicle ECU which controls all electronic functions on the car, truck, or SUV. Like any electronic device, the best way to determine how well the wheel speed sensor is working is to measure voltage output with a voltmeter. Since most car owners don't have access to this tool, they have to rely on the warning signs that might indicate that this component is starting to wear out or has broken and needs to be replaced as soon as possible.

Noted below are a few of the warning signs of a bad or failing wheel speed sensor for your review.

1. ABS Light is illuminated on the dashboard

Since the wheel speed sensor also monitors the anti-lock braking system on your car, it's common for the ABS Light to illuminate when the sensor is worn out, disconnected, or has been struck by debris, which means you'll have to replace the wheel speed sensor. There are other problems that will also cause this light to illuminate including a faulty ABS pump, worn out brake pads, low brake fluid levels, issues with brake pressure, or air trapped in the brake lines.

Because of the seriousness of brake component failure or damage to your brakes, it's very important to contact an experienced mechanic as quickly as possible if you see the ABS Light on your dashboard lit as you drive.

2. ABS does not work properly

The anti-lock braking system is designed to apply smooth application of brake fluid to engage the brake calipers and pads to slow your car without locking up the tires. The wheel speed sensor is responsible for relaying the wheel speed to the ECU so that it can tell the ABS system how much pressure to safely apply. When the wheel speed sensor is broken or not working as it should, one of the first things that are affected is the ABS system.

If you press your brakes and you notice that the front tires lock up, you should immediately contact a local ASE certified mechanic to inspect this problem. This problem can be a safety concern and should not be put off. If needed, it's recommended to stop driving the vehicle until a mechanic diagnoses the problem and fixes the ABS system. In the best case scenario, it will be a faulty wheel speed sensor that simply needs to be replaced.

3. Traction Control Light is active

The Traction Control Light on modern cars typically is illuminated when the driver of the car turns the system off. If you didn't complete this step or if the traction control is active, the most common reason that the light is illuminated is due to a faulty wheel speed sensor. The wheel speed sensor also monitors wheel speed and sends the data to the traction control system; which is why this warning sign is commonly due to a worn out or broken wheel speed sensor.

As with the ABS system, traction control is a safety device for cars, trucks, and SUVs. It's designed to ensure the tires don't break loose while the throttle is applied. If you notice that the traction control light is on, and you didn't turn it off, contact a local ASE certified mechanic immediately.

You can clearly see that the wheel speed sensor does much more than simply count how many revolutions your tire makes each second. It sends valuable data to the car’s onboard computer every millisecond, which is why it's very critical to the safe operation of your vehicle. If you notice any of the above warning signs, don't delay – contact a local ASE certified mechanic partnered with YourMechanic as soon as possible.

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

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

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

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.


Post a question and get free advice from our certified mechanics.


More related articles

P0121 OBD-II Trouble Code: TPS "A" Circuit Range Performance Problem
P0121 code definition Throttle Pedal Position Sensor/Switch (TPS) A Circuit Range Performance Problem What the P0121 code means P0121 is a generic OBD-II code which indicates that the Engine Control...
P0222 OBD-II Trouble Code: Throttle/Pedal Position Switch/Sensor B Circuit Low Input
P0222 code definition Throttle/Pedal Position Switch/Sensor B Circuit Low Input What the P0222 code means The manufacturer specifies a range of acceptable voltage to be produced from the throttle position...
The Traveler’s Guide to Driving in Malaysia
CraigBurrows / Malaysia is a popular destination for many tourists today. The country has amazing sights and attractions that you will want to explore....

Related questions

Q: At green light, accelerated, engine revved, but car barely moved

Hello. It sounds like that there was a glitch inside the TCM, known as the transmission control module. There is a TCM update available for your vehicle. Call your dealership to see if the update has been done already or...

Q: after replacing the master cyclinder and bleeding the brake the abs is not coming on when stopping short

The ABS will only activate when one wheel loses traction while stopping or you stop fast enough to cause the tires to skid. When you first start the vehicle you should see the ABS system light come on and go...

Q: How does traction control help me maintain control of my car?

Introduced back in 1987 but required since 2012, traction control is a great standard feature found on almost all modern vehicles. Traction control utilizes the anti-lock braking system (ABS) and the vehicle’s throttle, for vehicles that are equipped with an...