Rear Wheel Speed Sensor: Description

The antilock brake system uses two-wire wheel speed sensors, known as active wheel speed sensors. The sensors use an electronic principle known as magnetoresistive to help increase performance and durability. The sensors convert wheel speed into a small digital signal. A wheel speed sensor (WSS) is used at each wheel. The gear (tooth) type tone wheel serves as the trigger mechanism for each sensor. At each wheel of the vehicle there is one wheel speed sensor and one tone wheel.

The rear wheel speed sensors are mounted through the disc brake adapter or drum brake support plate. The rear tone wheels are mounted to and rotate with the hub and bearing assemblies. See Fig 1 and Fig 2.

The WSS air gaps are not adjustable. For the WSS air gap specification, (Refer to SPECIFICATIONS) . Each WSS is serviced individually. The tone wheels are serviced as an assembly with the hub and bearing assemblies.

Fig 1: Left Rear Wheel Speed Sensor

Courtesy of DAIMLERCHRYSLER CORP.

Fig 2: Right Rear Wheel Speed Sensor

Courtesy of DAIMLERCHRYSLER CORP.