Vehicle Speed Sensor: Description and Operation

Vehicle Speed Sensor:

PURPOSE
To provide a vehicle speed signal in the form of a varying pulse voltage to the Engine Control Module (ECM).

DESCRIPTION
The vehicle speed sensor (VSS) is a magnetic reed switch that rotates in conjunction with the transmission output shaft.

OPERATION
The VSS signals the ECM in open/closed terms. The ECM interprets the speed at which the open/closed signals are conducted and converts the signal into a representation of vehicle speed.

NOTE: A Diagnostic Trouble Code (DTC) will be stored for the VSS if a failure in its circuit is detected by the ECM.
- Vehicle Speed Sensor DTC No. 14.