Crankshaft Position Sensor: Description and Operation

PURPOSE
The Crankshaft Position (CKP) sensor is the primary sensor for ignition information to the integrated Ignition Control Module (ICM).

CONSTRUCTION
The CKP sensor is a magnetic transducer mounted on the engine block adjacent to a 36 minus one tooth trigger wheel located on the crankshaft. The trigger wheel has a total of 35 teeth spaced 10 degrees apart with one empty space for a missing tooth.

OPERATION
By monitoring the trigger wheel, the CKP output is a spiked sine wave that is proportional to crankshaft speed and position information to the integrated ICM. By monitoring the missing tooth (36 minus 1) design, the CKP is also able to identify piston travel in order to synchronize the ignition system and provide a way of tracking the angular position of the crankshaft relative to fixed reference.