Camshaft Hall Sensor, Basic Function - GF15.10-D-2001A
Engine All (Light transporter)
Example illustration of engine 654
Overview
This document contains information on:
- General
- Location
- Function
General
The camshaft Hall sensors detect the camshaft positions contactlessly for the following functions:
- Camshaft adjustment
- Synchronization of ignition and injection sequence
- Recognition of ignition TDC (top dead center)
- Emergency engine start in case of defective crankshaft Hall sensor
The camshaft Hall sensors are on the cylinder head above the respective camshaft.
Location
The camshaft Hall sensors are at the camshaft ends on the cylinder head.
Function
The camshaft positions are detected by the camshaft Hall sensors. The camshaft Hall sensors detect the positions of the segments (of 180° camshaft revolution) on the corresponding camshaft.
The signal voltages of the camshaft Hall sensors are approx. 12 V (high), if the segments are not above the camshaft Hall sensors. When the segments move past the camshaft Hall sensors, the signal voltages of the camshaft Hall sensors drop to approx. 0 V (low).
The camshaft Hall sensors detect the camshaft positions when the engine is off, which enables quick starting of the combustion engine. This improves the exhaust gas values when starting the combustion engine because each cylinder can be immediately assigned the optimum fuel injection quantity.
If the signal from the intake camshaft Hall sensor is implausible or incorrect, the signal from the exhaust camshaft Hall sensor is used to detect the ignition TDC of cylinder 1.
The gaps between the camshaft Hall sensors and the segments at the camshafts are not adjustable; they are predetermined by the installation position and cannot be adjusted.