What is a wheel speed sensor?
In modern vehicles (cars made since 2004), every wheel (including the front wheels and rear wheels) has a small sensor mounted in the wheel hub near the brake calipers. The sensor, also called an ABS wheel speed sensor, tracks how fast the wheel’s axle turns and transmits this information to the ABS and TCS systems.
If ACS or TCS senses dangerous driving conditions, they’ll activate and reduce power to your brakes so you don’t spin out or slide.
When should I replace a wheel speed sensor on my car?
Here are the most common signs of a bad wheel sensor:
The anti-lock brake system ABS warning light comes on: This light may come on when you’re not driving in slippery conditions. It’s a good idea to get the wheel speed sensors checked if this happens.
ABS does not work properly: If the wheel speed sensors aren’t communicating with ABS, you’ll notice that the system doesn’t work when you’re driving in icy conditions, or it will work when you don’t need it to.
The traction control (TCS) light is on: If the TCS light illuminates and doesn’t say “OFF” underneath, it means that the wheel speed sensor is telling TCS that a wheel is losing its grip. The system might apply brakes to that wheel because it believes it’s slipping.
The check engine light comes on: This is more common in older cars. You might also notice that the speedometer isn’t accurate.
How often should a wheel speed sensor be replaced?
Most wheel speed sensors last 30,000 to 50,000 miles. Unfortunately, there’s no guarantee that they’ll last that long! The speed sensors sit close to the road, where they’re exposed to grit, debris, salt, and brake dust. This can accumulate around the sensor, causing it to malfunction.
Can I replace a wheel speed sensor myself?
While you might be trying to save on repair costs, it’s best to leave the replacement to the professionals because you’ll be working closely with the car’s brake system. You might even have to remove the brake pads and rotors. A mechanic will have specialized parts and tools to get the job done.