DTC P0500: Vehicle Speed Sensor (M/T): Description
WARNING: This page is about a different car, the 2002 Pontiac Firebird and 2002 Chevrolet Camaro. However, it is still accessible from the selected car via links, so may be relevant.
A toothed wheel mounted on the output shaft of the transmission generates an AC voltage pulse as it moves past the Vehicle Speed Sensor (VSS). The VSS contains a permanent magnet surrounded by a coil of wire, which produces a magnetic field. The toothed wheel interrupts the magnetic field that generates an AC voltage pulse. As the vehicle speed increases the AC voltage pulse rate also increases.