Vehicle Speed Sensor (VSS)

Depending upon vehicle application, VSS is either a Permanent Magnet (PM) generator mounted in transmission or a Light Emitting Diode (LED) in instrument panel cluster, behind speedometer. The VSS sends a pulsing signal to ECM, which ECM converts into miles per hour (MPH). This sensor input is used by ECM in controlling Torque Converter Clutch (TCC). The VSS circuit may be diagnosed by using chart for Code 24.