CAMSHAFT POSITION SENSOR
The Camshaft Position (CMP) sensor detects the position of the camshaft. The CMP sensor identifies when piston No.1 is on its compression stroke. A signal is then sent to the Powertrain Control Module (PCM) and used for synchronizing the firing of sequential fuel injectors. The Coil On Plug (COP) Ignition applications also use the CMP signal to select the proper ignition coil to fire. The input circuit to the PCM is referred to as the CMP input or circuit.
Typical Hall-Effect Sensor
Typical Variable Reluctance Sensor
There are two types of CMP sensors: the three pin connector Hall-effect type sensor (Figure 22) and the two pin connector variable reluctance sensor (Figure 23).