Camshaft Position Sensor: Description and Operation

CAMSHAFT POSITION (CMP) SENSOR

This engine uses four CMP sensors, one for each camshaft. The CMP sensor signals are a digital ON/OFF pulse, output tour times 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 ECM to determine the position of the four camshafts relative to the crankshaft position. By monitoring the CMP and CKP signals the ECM can accurately time the operation of the fuel injectors. The ECM supplies the CMP sensor with a 5-volt reference circuit and a low reference circuit. The CMP sensor signals are an input to the ECM. These signals are also used to detect camshaft alignment with the crankshaft.