SENSOR, Crankshaft Position: Operation: 4.7L

WARNING: This page is about a different car, the 2011 RAM Pickup and 2011 RAM Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.

Fig 1: CKP Sensor Operation And Tonewheel - 4.7L V-8

Courtesy of CHRYSLER LLC

1 - TONEWHEEL

2 - NOTCHES

3 - CRANKSHAFT POSITION SENSOR

4 - CRANKSHAFT

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 combined with an internal magnet. It is also sensitive to steel within a certain distance from it.

A tonewheel (1) is bolted to the engine crankshaft. Refer to Fig 1. This tonewheel has sets of notches (2) at its outer edge. Refer to Fig 1.

The notches cause a pulse to be generated when they pass under the sensor. The pulses are the input to the PCM.