Speedometer and Odometer

An electronic circuit operates the speedometer. The Vehicle Speed Sensor (VSS), located in the transaxle, generates an ac voltage with a frequency proportional to the speed of the vehicle. The voltage goes to the Powertrain Control Module (PCM) and then to the speedometer circuit board in the instrument cluster. The solid state unit drives the pointer of the speedometer.

The same buffered speed signal from the PCM is processed by the speedometer circuit board in order to drive the odometer. The odometers are operated by a stepper motor that responds to pulses from the speedometer circuit.