Description And Operation
The Camshaft Position (CMP) sensor is an internally magnetic biased digital output integrated circuit sensing device. The sensor detects magnetic flux changes between the peaks and valleys of the tone wheel attached to the camshaft. The CMP sensor is located on the cylinder head and faces the camshaft.
As each tooth of the camshaft tone wheel rotates past the CMP Sensor, the resulting change in the magnetic field is used by the sensor electronics to produce a digital output pulse. The sensor returns a digital ON/OFF DC voltage pulse of varying frequency output pulses per camshaft revolution that represent an image of the camshaft tone wheel. The frequency of the CMP Sensor output depends on the velocity of the camshaft. The Powertrain Control Module (PCM) decodes the tooth pattern to identify camshaft position. The CMP sensor is used by the PCM in conjunction with the Crankshaft Position (CKP) sensor to determine the camshaft relative position to the Crankshaft in order to sequence the ignition timing, fuel injection, and Variable Valve Actuator (VVA) operation for the engine.