Vehicle Speed Sensor

Vehicle Speed Sensor (VSS) is a variable reluctance or Hall Effect type sensor that generates a waveform with a frequency that is proportional to vehicle speed. When vehicle is moving slowly, sensor produces a low frequency signal. As vehicle speed increases, sensor produces a higher frequency signal. PCM uses this signal to control fuel injection, ignition timing and transaxle/transmission shift and Torque Converter Clutch (TCC) scheduling.