FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
Courtesy of Operation CHARM: Car repair manuals for everyone.

Operation







OPERATION

The crankshaft position and engine speed are detected based on the hall effect. Gaps in the crankshaft position sensor tone wheel, which is mounted to the flywheel, allow the crankshaft sensor to generate a digital voltage signal based on crankshaft position. The distance between the crankshaft position sensor and the surface 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 solid metal portion of the tone wheel generates a voltage pulse while and the gap in the tone wheel generates no voltage pulse.

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 voltage signal from the crankshaft sensor, is analyzed by the ECM in order to detect the TDC position of cylinder 1