Sensor, Wheel Speed, Front: Operation

The active WSS receives a 12 volt signal from the Antilock Brake System (ABS) module. As the wheel rotates it converts the signal into a digital square wave and sends that signal back to the ABS module. The return message to the ABS module is a 7-14 mA signal to determine wheel speed.

The signal can be affected by an excessive air gap, however, the WSS is mounted in a fixed position and cannot be adjusted.

A loose connection or corrosion can also affect the operation and may cause the WSS signal to drop out at speeds less than 64 km/h (40 mph).