Crank Angle Sensor

The signal from the hall effect sensor in the distributor is used to determine crankshaft angle (relative to the next ignition fire). While its signal does not describe the exact position of the crankshaft (which cylinder is firing), it does describe the number of degrees of crankshaft rotation remaining before TDC of each firing stroke. The hall effect sensor generates a square wave signal which the ECU "reads". The beginning of each wave pulse indicates approximately 60~ of crank rotation before TDC of the next firing stroke. For more information, refer to HALL SENSOR.