Grand Cherokee 2WD Limited V8-4.7L (2002)
Fig. 20 CKP Sensor Operation And Tonewheel - 4.7L V-8 Engine
On this engine, a tonewheel is bolted to the engine crankshaft. This tonewheel has sets of notches at its outer edge.
The notches cause a pulse to be generated when they pass under the sensor. The pulses are the input to the PCM.
