Vehicle Speed Sensor: Description and Operation

The vehicle speed sensor (VSS):

- is mounted to the transaxle

- is a magnetic pickup driven by a gear which is driven by the transaxle.

- sends a signal to the speed control servo proportional to vehicle speed.

Vehicle Speed Sensor (VSS):

The Vehicle Speed Sensor (VSS) is a variable reluctance sensor that generates a waveform with a frequency that is proportional to the speed of the vehicle. If the vehicle is moving at a relatively low velocity, the sensor produces a signal with a low frequency. As the vehicle velocity increases, the sensor generates a signal with a higher frequency. The PCM uses the frequency signal generated by the VSS (and other inputs) to control such parameters as fuel injection, ignition timing, transmission/transaxle shift scheduling and torque converter clutch scheduling.