Camshaft Position Sensor: Description and Operation

The camshaft position sensor located in the distributor consists of the signal generator (pick-up coil and magnet) and signal rotor. As the signal rotor turns, AC voltage is generated in the pickup coil which varies in pulsatory way as shown. This pulse signal (5 pulses/revolution) is sent to ECM where it is used to calculate the engine speed and to distinguish each cylinder, and also as one of the signals to control various devices.