Vehicle Speed Sensor

The vehicle speed sensor (VSS) is mounted on the transmission assembly. The VSS produces an AC signal. The frequency of the signal is proportional to the rotational speed of the transmission assembly output shaft. The rotational speed is proportional to the speed of the vehicle.

The VSS buffer amplifies and converts the AC signal which the VSS produces. The VSS buffer assembly supplies the signal to the following components:
^ The PCM
^ The cruise control module
^ The speedometer

The VSS buffer opens and closes internal solid state switches to ground in order to produce the signal. The PCM converts the signal to 4000 pulses per mile.

The signal reaches the cruise control module and the speedometer assembly at a rate of 4000 pulses per mile. The control module and speedometer assembly internally convert the number of pulses per mile to pulses per second in order to determine vehicle speed.