Your vehicle is jam-packed with sensors delivering an endless array of crucial information to the ECU and other important modules. Among them is the ABS wheel speed sensor, responsible for picking up data from each individual wheel to feed to the ABS system. A failed sensor can cause your ABS system, not to mention other systems reliant on ABS data, to work poorly or not work at all. A typical ABS wheel speed sensor failure usually comes with a few warning signs, as explained below.
Sign #1: The ABS Light Stays On
Your car’s ABS light serves the same function as the Check Engine Light: it tells you when something is amiss with your ABS system. You’ll see this light flash momentarily as you turn the key, but a steady ABS light that stays on throughout the drive is a common sign that something’s wrong with your ABS system. A failed ABS sensor will cause the ABS light to appear on the dashboard.
Sign #2: Traction and/or Stability Control is Disabled
Your car’s antilock brakes aren’t the only components that rely on the ABS wheel speed sensor for proper operation. The stability and/or traction control systems may also use data from the ABS sensor for stability control, hill-start assist, and a variety of other functions. A failed ABS wheel speed sensor could potentially prevent those systems from working and they’ll remain disabled until a new sensor is installed.
Sign #3: It Takes Longer to Stop Your Vehicle
It takes more than good brake pads to bring your vehicle to a quick, safe stop. The ABS system works in tandem with the rest of the braking system to stop your vehicle quickly under hard braking. A faulty ABS wheel speed sensor can lead to longer braking distances under those situations.
Sign #4: Your Vehicle Becomes Unstable During Braking
Under normal operation, the ABS system activates upon heavy braking to quickly slow the vehicle without locking up the brakes and sending the vehicle into a skid. The ABS wheel speed sensor uses the data it collects to modulate brake pressure to prevent lock-up and traction loss during hard stops. Preventing brake lock-up and avoiding a skid becomes much harder, especially on wet or icy roads.
Sign #5: ABS Works Erratically
Another common symptom of ABS sensor failure is an ABS system that sometimes works and sometimes doesn’t. An erratic ABS system can actually compromise your vehicle’s safety since you’ll never know when it’s properly working, and there’s no guarantee that it will work when you need it most.
Spotting these aforementioned signs of ABS sensor failure means you can have your vehicle diagnosed and repaired sooner.