Circuit Description

The vehicle speed sensor (VSS) is mounted on the transaxle. As the transaxle turns the VSS, the VSS provides the speedometer with a vehicle speed input through voltage pulses. Each revolution of the axleshaft equals 4 pulses. This input is used to drive the speedometer.

The speedometer converts the vehicle speed input to a more precise output which is sent to the powertrain control module (PCM) and the cruise control module, if equipped. The PCM sends a 5-volt carrier signal to the speedometers vehicle speed output control circuit. On this same circuit, the speedometer produces a pulse width modulated signal that the PCM, and the cruise control module, use to determine the vehicle speed.