Camshaft Position Sensor: Description and Operation

The Camshaft Position (CMP) sensor signal is a digital ON/OFF pulse, output once per revolution of the camshaft. The CMP sensor does not directly affect the operation of the ignition system. The CMP sensor information is used by the Powertrain Control Module (PCM) to determine the position of the valve train relative to the crankshaft. By monitoring the CMP and CKP signals the PCM can accurately time the operation of the fuel injectors. The CMP sensor is connected to the PCM by a 12-volt, low reference, and signal circuit.