Circuit Description

Speed sensor at each wheel produces an A/C signal to ABS/TRAC/VSC ECU as 48 tooth rotor passes permanent magnet sensor. Frequency of A/C signal changes with wheel speed. DTC is set under any of the following conditions:

• No speed sensor pulses are input to ECU for 15 seconds with vehicle speed 6 MPH or greater.
• Momentary interruption of speed sensor signal occurs at least 7 times during cycle of ignition switch.
• Abnormal speed sensor signal fluctuation with vehicle speed of 12 MPH or greater.

If fault occurs in speed sensor circuit, ABS/TRAC/VSC ECU performs a fail safe function, turning off current to ABS solenoid relay and prohibiting ABS, TRAC, and VSC. Possible causes are:

• Right Front Speed Sensor
• Right Front Speed Sensor Circuits
• Right Front Speed Sensor Rotor
• ABS/TRAC/VSC ECU