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Crankshaft Position Sensor: Description and Operation

PURPOSE
The crankshaft position sensor generates a frequency signal used by the ECM to determine piston location.

Crank Angle Sensor:




Crank Angle Sensor Output Signal:





OPERATION
The sensor generates a signal whenever the engine is rotating. As a tooth on the crankshaft pulley passes below the sensing head, a small electrical pulse is generated. This signal is combined with the cam angle sensor to determine the position of all pistons in their cylinders.