Caprice Wagon V8-350 5.7L (1994)
Vehicle Speed Sensor: Description and Operation
General Description
Vehicle Speed Sensor Circuit.
PURPOSE
The VSS produces an A/C voltage signal that increases with vehicle speed. The PCM processes this signal and sends it to the instrument panel,
Power Steering Control Module, chime module and cruise control module on CKT 817.
The VSS also provides the PCM with a transmission output shaft speed signal on CKT 400. The PCM uses this signal for the following:
^ Calculates vehicle speed, trans output speed and TCC slip speed
^ Controls shift quality
OPERATION
The VSS system uses an inductive sensor mounted in the tail housing of the transmission and a toothed reluctor wheel on the tail shaft. The VSS
produces an AC voltage signal that increases with vehicle speed.
LOCATION
The Vehicle Speed sensor is mounted in the output shaft housing of the transmission.
