DeVille V8-4.9L VIN B (1995)
Vehicle Speed Sensor: Description and Operation
General Description
Vehicle Speed Sensor
DESCRIPTION
The Vehicle Speed Sensor (VSS) is a pulse generator mounted in the transaxle. A toothed reluctor ring rotates near a magnetic pickup which
produces a varying voltage signal in the pickup coil. This voltage signal varies in proportion to vehicle speed and is sent to the Powertrain Control
Module (PCM), where it is converted to MPH.
The PCM uses VSS information for fuel economy calculations, cruise control, idle speed control, transaxle shifts, and to control fuel under certain
conditions. A faulty VSS may cause various transaxle and engine driveability conditions and should set a Diagnostic Trouble Code.
