Camshaft Position Sensor: Description and Operation

GF07.04-P-6020MAR Camshaft Hall Sensor, Component Description
- refinement package
- as of model year 09

Component Identification:

Location
The Hall sensors are located at the front on the cylinder head, in front of the respective camshaft.

Task
The Hall sensors contactlessly detect the camshaft positions for the following functions over the pulse wheel on the camshafts:
- Camshaft adjustment
- Synchronization of the ignition and injection sequence (detection of ignition TDC).
- Emergency start for a defective camshaft Hall sensor (B70)

Design
They consist of a Hall sensor cast in a plastic housing with a 3-pin plug connection.
In the installation position, there is a gap of 0.2 to 1.8 mm between the Hall sensors and the pulse wheel.

Function
Detection of the camshaft takes place via the position of the camshaft pulse wheels. The camshaft positions are already detected at engine OFF by the electronics in the Hall sensors. Exhaust emission values are improved because the optimal injection quantity can be immediately assigned to each cylinder at engine start (quick start function).

4 signals are generated for each rotation of the camshaft. To do this, the signal is switched between about 5 V (high) and about 0 Volt (low). If a notch in the pulse wheel is positioned opposite a Hall sensor, the signal is about 5 V.

Component Identification:

The specified angles on the pulse wheel are camshaft angles and must be doubled in order to obtain the corresponding crankshaft angle.