Crankshaft Position Sensor: Description

The crankshaft position sensor is located opposite the teeth on the flywheel and uses a non contact method to record the position of the crankshaft. The leading edges of each tooth on the flywheel generate a positive signal in the position sensor, while the trailing edges generate a negative signal. When the crankshaft is rotating, an alternating voltage is produced as a result.

The period of the signal is the time required by the crankshaft to turn through the gap between two flywheel teeth. The clearance between the crankshaft position sensor and the teeth of the flywheel is fixed by the installation.

Two teeth on the flywheel are missing. The resulting signal gap is used by the ECM to detect the TDC position of cylinder number one.