Measures the wheel speed, a critical component of the ABS and stability control system
If your BMW has lights on the dash showing an ABS/DSC failure this little sensor can be a potential culprit. This sensor measures wheel speed and provides the information required for your BMW's ABS and DSC systems to function properly. This is the same sensor which you would buy from your local BMW dealer.
A wheel speed sensor, also known as an ABS wheel speed sensor, is part of your vehicles anti lock brake system. The wheel speed sensor measures the exact speed of a corner of your vehicle. In total all vehicles with an ABS system will have four sensors. The wheel speed sensors are also used as reference points for traction control as well as stability control.
The wheel speed sensor measures wheel speed via a reluctor wheel or magnet located near the wheel hub. On some vehicles the reluctor can be part of the wheel bearing or it may be present on the wheel hub or axle. In some cases, a bad wheel bearing can be the cause for an ABS fault so it's recommended to do a full diagnoses on the ABS system and correlated parts before going into a repair
Depending on the vehicle the ABS wheel speed sensor may be a serviceable item or it may be part of a wheel hub assembly. In either case, a failed ABS wheel speed sensor will cause the ABS system to stop functioning and will also likely cause other systems such as traction and stability control to not function as well.
ABS Wheel Speed Sensor Failure Symptoms