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Vehicle Speed Sensor: Description and Operation

Vehicle Speed Sensor (VSS):




The VSS is an electronic relay that is mounted on the transaxle. As the transaxle turns the VSS, the VSS provides the speedometer with a vehicle speed input through voltage pulses. This input is used to drive the speedometer. The speedometer then converts this vehicle speed input into a more precise waveform and provides the PCM and the cruise control module, if equipped, with the vehicle speed input. The PCM converts this input (ground pulses) into a vehicle speed.