Vehicle Speed Sensor: VSS
WARNING: This page is about a different car, the 2002 Pontiac Sunfire, 2002 Chevrolet Cavalier, 2001 Pontiac Sunfire, and 2001 Chevrolet Cavalier. However, it is still accessible from the selected car via links, so may be relevant.
The Vehicle Speed Sensor (VSS) is mounted on transaxle case extension housing. VSS produces an AC signal with a frequency proportional to speed at which transaxle assembly output shaft rotates, which is also proportional to vehicle speed. AC signal produced by VSS is amplified and converted by VSS buffer assembly. The AC signal is sent to Powertrain Control Module (PCM), Cruise Control Module (CCM) and speedometer where signal is sent at a rate of 4000 pulses per mile. PCM converts number of pulses per mile to pulses per second to determine speed of vehicle