The task of a camshaft sensor is to work with the crankshaft sensor to define the exact position of the crankshaft drive. Through the combination of both sensor signals, the engine control unit knows when the first cylinder is in the top dead point. The camshaft sensor works according to the Hall principle. It scans a ring gear on the camshaft. The rotation of the ring gear changes the Hall voltage of the Hall IC in the sensor head. This change in voltage is transmitted to the control unit and evaluated there in order to establish the required data.
A faulty camshaft sensor can cause the following symptoms:
- Starting difficulties
- Engine indicator lamp comes on
- Fault code is stored
- Control unit enters an emergency program
Reasons for failure of the camshaft sensor can be:
- Mechanical damage
- Break in the encoder wheel
- Internal short circuits
- Interruption in connection to the control unit.