Sensor-Crankshaft Position: Operation

WARNING: This page is about a different car, the 2006 Dodge Magnum, 2006 Dodge Charger, and 2006 Chrysler 300. However, it is still accessible from the selected car via links, so may be relevant.

The crankshaft position and engine speed are detected contactless signal (hall effect). The distance between the crankshaft position sensor and the gaps of the tone wheel is fixed by the installation position.

When the crankshaft rotates, an alternating voltage is generated in the crankshaft position sensor by the gaps of the tone wheel located behind the flex plate.

In this case, the metal portion of the tone wheel generates a positive voltage pulse and the gap in the tone wheel a negative voltage pulse. The distance from the positive to the negative voltage peak equals the length of the gap.

The gap created by 3 missing teeth has the effect that no voltage is generated in the crankshaft position sensor. This gap, or time without a signal from the crankshaft sensor, is analyzed by the ECM in order to detect the TDC position of cylinder 1