Crankshaft Position Sensor: Description and Operation

PURPOSE/OPERATION
The crankshaft position sensor detects the crankshaft angle (position) of each cylinder, and converts that data to pulse signals, which are then input to the engine control module. The engine control module, based upon those signals, calculates the engine rpm, and also regulates the fuel injection timing and the ignition timing.
The power for the crankshaft position sensor is supplied from the ignition switch (IG) and is grounded to the vehicle body, The crankshaft position sensor produces pulse signals by intermitting the flow (to ground) of the voltage applied from the ignition switch.