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Vehicle Speed Sensor: Description and Operation

PURPOSE
There are two sensors used to monitor actual vehicle speed. Vehicle speed information is used by the ECU for fuel injection, air injection (on equipped vehicles), cruise control and electronic control of automatic transmissions.

OPERATION
VSS No. 1 is mounted on the speedometer head and inputs the ECU through terminal SP1. VSS No. 2 is mounted on the transmission and inputs the ECU through terminal SP2.