Circuit Description

The Vehicle Speed Sensor (VSS) is mounted on the transaxle. As transaxle turns, VSS provides speedometer with a vehicle speed input through voltage pulses. Each revolution of the axle shaft equals 4 pulses. This input is used to drive the speedometer. The speedometer converts vehicle speed input to a more precise output which is sent to Powertrain Control Module (PCM) and cruise control module, if equipped. PCM sends a 5-volt carrier signal to speedometers vehicle speed output control circuit. On this same circuit, the speedometer produces a pulse width modulated signal that the PCM, and cruise control module use to determine vehicle speed.