Circuit Description

Toothed wheel generates a voltage pulse as it moves past sensor. EBCM uses these pulses to determine wheel speed. The amount of voltage generated in each pulse depends on air gap between sensor and toothed wheel and wheel speed. EBCM uses wheel speed sensor signal to calculate vehicle reference speeds and individual speed, acceleration and slip values for each wheel. These values are used to determine when anti-lock control is needed. EBCM performs 2 basic types of checks on wheel speed sensors: sensor continuity and sensor output.

Code 25 will set if open or short exists in circuit No. 830, open exists in circuit No. 873 or an open across sensor coil.

Code 25 will also set if low output from wheel speed sensor is detected by EBCM. Conditions include shorted sensor coil or an improperly installed wheel speed sensor.