P42.45-2232-06
The diagram shows the current path through the active wheel speed sensor during an acceleration phase
1 Active sensor
2 Reluctor with mutiple trigger points
3 Sample of signal output from wheelspeed sensor
Function of the active wheel speed sensor
The strength and direction of an external magnetic field causes a change in the internal resistance inside the sensor. An electronic analysis system accommodated in the sensor produces a square-wave signal, whose frequency is proportional to the rotational speed but whose amplitude is constant. This signal is received by the relevant dynamic handling control system and transmitted over the CAN.
A reluctor with multiple trigger points generates the external magnetic field.
This consists of an elastomer plastic containing metallic particles. These are aligned by a special magnetization method so as to produce various magnets whose polarity at the circumference alternates from north to south.