Camshaft Position Sensor: Description and Operation
Camshaft Position SensorCamshaft Position (CMP) Sensor:
The PCM receives engine rotational position information from the Camshaft Position (CMP) sensor. The CMP is a hall-effect device. It outputs 12 volts to the PCM whenever it detects the iron of a spoked target wheel in front of it, and it outputs 0 volts whenever it detects the space between the spokes. The target wheel spokes and spaces are each 15 crank degrees, except for narrow spoke which indicates cylinder No.1 and a wide spoke which indicates cylinder No.4 (fires 5th). The NGS PID RPM is generated by the PCM from the CMP signal.