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Vehicle Speed Sensor: Description and Operation

Circuit Description
The vehicle speed sensor installed on the speedometer driven gear generates pulse signals, which indicate the vehicle speed, and provides the signals to the control modules (cruise control module, ECM, PCM and ETACS control module).

The control modules calculate the vehicle speed and send signals to control appropriate actuator. The vehicle speed sensor (VSS) intermittently grounds the circuits and the number of pulses per minute increases/decreases with the speed of the vehicle.