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Camshaft Position Sensor: Description and Operation




The CMP sensor (1) is mounted on the rearward of cylinder head. As the sensor has a built-in hall element (2) (element which generates voltage from changes in the magnetic flux) and a waveform forming circuit it converts changes in the magnetic flux caused by rotation of the signal rotor (3) into electric pulse signals.

Receiving this pulse signal, ECM (PCM) (4) detects the engine speed and the piston position of each cylinder and uses that information as one of signals to control various devices.