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Vehicle Speed Sensor (VSS)

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 PCM, where it is converted to MPH.

OPERATION
The PCM uses VSS information for fuel economy calculations, idle speed control, transaxle shifts, and to control fuel under certain conditions.

CIRCUIT FAULTS
A faulty VSS may cause various transaxle and engine driveability conditions and should set a PCM Diagnostic Trouble Code. Refer to Diagnostic Tables for diagnosis. Testing and Inspection