Camshaft Position (CMP) Sensor

The CMP sensor detects the position of the camshaft. The CMP sensor identifies when piston number 1 is on its compression stroke. A signal is then sent to the PCM and used for synchronizing the sequential firing of the fuel injectors. Coil-on-plug (COP) ignition applications use the CMP signal to select the correct ignition coil to fire.

Vehicles with 2 CMP sensors are equipped with variable camshaft timing (VCT). They use the second sensor to identify the position of the camshaft on bank 2 as an input to the PCM.

There are 2 types of CMP sensors: the 3-pin connector Hall-effect type sensor and the 2-pin connector variable reluctance type sensor.

Fig 1: Typical Synchronizer Hall-Effect CMP Sensor

Courtesy of FORD MOTOR CO.

Fig 2: Identifying Camshaft Position (CMP) Sensor

Courtesy of FORD MOTOR CO.