TC BY Maserati V6-181 2972cc 3.0L SOHC VIN S FI (1991)
Wheel Speed Sensor: Description and Operation
Wheel Speed Sensors and Tonewheels
The wheel speed sensors operate as a generator. A permanent magnet located in the sensor is passed by a toothed sensor wheel (tonewheel). This
causes a disturbance in the magnetic field pushing the signal high as a tooth passes and drawing the signal low in the spaces. This creates an AC
signal that is sent to the anti-lock brake module (ABCM) to be processed. The ABCM monitors the frequency or time between the teeth to
determine the speed of the vehicle.
