Sensor, Crankshaft Position: Operation
The engine speed and crankshaft position are provided through the CKP (Crankshaft Position) sensor (3). The sensor generates pulses which sends an input signal to the Powertrain Control Module (PCM). The PCM interprets the sensor input signal to determine the crankshaft position. The PCM then uses this information, along with other inputs, to determine injector sequence and ignition timing.
A tone wheel (targetwheel) is bolted to the engine crankshaft (1). This tone wheel has notches (2) on the outer edge.
The sensor (1) is a hall effect device combined with an internal magnet. It is also sensitive to steel within a certain distance from it.
The notches (3) cause a pulse to be generated when they pass under the sensor. The generated pulses are the input signal to the PCM.