Beretta L4-138 2.3L DOHC QUAD 4 HO MFI VIN A (1994)
Vehicle Speed Sensor: Description and Operation
General System Description
Vehicle Speed Sensor (VSS)
PURPOSE
The Vehicle Speed Sensor (VSS) provides information to the ECM/PCM for control of transmission Torque Converter Clutch (TCC),
speedometer, odometer and cruise control.
OPERATION
The VSS is a Permanent Magnet (PM) generator that produces a pulsing A/C voltage whenever vehicle speed exceeds about 3 mph (5 kPh). The
A/C voltage level and the number of pulses increases with vehicle speed and is converted by the ECM/PCM to MPH (kPh). A VSS buffer is
incorporated into the ECM/PCM for operating the instrument panel speedometer and odometer.
LOCATION
Transaxle
