Vehicle Speed Sensor: Description and Operation

CIRCUIT OPERATION:
The vehicle speed sensor generates a signal proportional to vehicle speed. The signal produced is a sine wave, which the PCM processes into a square wave to supply inputs to the speedometer, Multi-Function Chime (MFC) module and the Computer Command Ride (CCR) controller (if equipped).

The PCM takes the sensor voltage pulses from the vehicle speed sensor and uses them to close solid-state output switches. The output terminals are switched to ground at a rate that is proportional to vehicle speed.