Vehicle Speed Sensor: Description and Operation

Vehicle Speed Sensor:

PURPOSE
To provide a varying signal that corresponds to vehicle speed.

OPERATION
The Vehicle Speed Sensor (VSS) is a magnetic pick up driven by the transmission speedometer gear. The VSS produces an Alternating Current (AC) signal and sends this signal to the Powertrain Control Module (PCM). The PCM converts this signal to a vehicle speed value. The PCM uses this value to aid in controlling A/T torque converter lock-up and 3-4 shift schedule.