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Exhaust Camshaft Sensor




Camshaft Sensor

The camshaft sensor registers the position of the camshaft with the aid of a sheet metal wheel with various apertures screwed to the camshaft. It operates in accordance with the Hall effect principle.

Hall effect
A permanent magnet in the sensor produces a magnetic field. A conductor with current flowing through it is located in this magnetic field. An electric voltage dependent on the strength of the magnetic field is produced in this conductor perpendicular to the current and perpendicular to the magnetic field. The magnetic field in the sensor is varied by the camshaft sensor wheel and its apertures rotating passed the sensor. The teeth and gaps on the sensor wheel can be recognized by means of the voltage.

Use of the camshaft sensor
It is necessary for the fully sequential injection system (fuel injection takes place individually for each cylinder at the specific firing point).

The variable camshaft control requires feedback of the current position of the camshaft for adjustment purposes.