FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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Wheel Speed Sensor: Description and Operation

WHEEL SENSOR





The sensor units consist of a gear-shaped sensor rotor and a sensor element. The element contains a bar magnet around which a coil is wound. The front sensors are installed on the back of the front brake rotors. For 2-wheel drive systems a single sensor is installed at the companion flange of the rear axle housing and for 4-wheel drive systems there is a sensor installed at each rear brake drum. As the wheel rotates, the sensor generates a sine-wave pattern. The frequency and voltage increase(s) as the rotating speed increases.