SL L4-1.9L SOHC VIN 8 (1997)
Wheel Speed Sensor: Description and Operation
These sensors provide a frequency and voltage signal that is proportional to the wheel speed. The sensor consists of wire windings wrapped around a
magnet. A toothed (47 teeth) speed sensor ring (spinning at road wheel speed) interrupts the magnetic field created by the wheel speed sensor, alternately
increasing and decreasing the strength of the field. This increasing and decreasing magnetic field creates a voltage and frequency signal in the sensor
wire windings that varies proportionally to road wheel speed. This signal is used by the antilock brake control module to determine the road wheel speed.
On the front wheels, the speed sensor is fastened to the steering knuckle. The front wheel speed sensor toothed ring is pressed onto the end of the axle
shaft assembly. On the rear wheels, both the wheel speed sensor and toothed ring are contained within the wheel hub/bearing assembly.
