The crankshaft speed and position sensor faces the marks on the flywheel. It consists of a magnetic core surrounded by a winding.
When the flywheel teeth pass the sensor, a change in the magnetic field is created in it, which causes an alternating voltage in the winding (sinusoidal signal) the frequency and amplitude of this voltage are proportional to the engine speed.
The flywheel has 60 teeth around its circumference, of which two are removed to determine the position of the TDC of the 1st cylinder.