Vehicle Speed Sensor (VSS)

VSS is a Permanent Magnet (PM) generator mounted in transmission or transfer case. The VSS sends a pulsing signal to the PCM/VCM or Digital Ratio Adapter Controller (DRAC), which passes the signal on to the PCM/VCM. PCM/VCM then converts this signal into Miles Per Hour (MPH) by monitoring the time interval between pulses. PCM/VCM uses this sensor input in controlling converter clutch engagement, shift speed, etc.