Sensor, Crankshaft Position: Operation
WARNING: This page is about a different car, the 2017 Jeep Cherokee. However, it is still accessible from the selected car via links, so may be relevant.
Engine speed and crankshaft position are provided through the CKP (Crankshaft Position) sensor. The sensor generates pulses that are the input sent to the Powertrain Control Module (PCM). The PCM interprets the sensor input to determine the crankshaft position. The PCM then uses this position, along with other inputs, to determine injector sequence and ignition timing.
The sensor is a hall effect device.
A tonewheel (targetwheel) is located on the rear of the crankshaft.
This tonewheel causes a pulse to be generated when passing under the sensor. The pulses are the input to the PCM.