Speedometer and Odometer

The Vehicle Speed Sensor (VSS) is a gear driven permanent magnet generator housed in the transaxle. The sensor generates a sine wave output with a frequency proportional to the vehicle speed. The Powertrain Control Module (PCM) converts the signal to an output that switches to ground at a frequency of 4000 pulses per mile. The signal (CKT 389) drives the speedometer and the odometer and is used by various vehicle components.