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Vehicle Speed Sensor/Transducer - Cruise Control: Description and Operation

DESCRIPTION
The vehicle speed sensor is mounted to the automatic transmission and produces and Alternating Current (AC) signal. The frequency of this signal is proportional to the speed in which the transmission output shaft rotates, which is proportional to the speed of the vehicle.

OPERATION
The AC signal produced by the sensor is supplied to the Engine Control Module (ECM), cruise control module and instrument cluster. The signal is transmitted at a rate of 4000 pulses per mile. The ECM, cruise control module and speedometer internally convert the number of pulses per miles per second to determine vehicle speed.