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Crankshaft Position Timing Ring: Description and Operation

CRANKSHAFT BALANCE INTERRUPTER RING

Each interrupter ring has blades and windows that either block the magnetic field or allow it to close one of the hall-effect switches. The outer hall-effect switch sends a pulse called the 18X reference signal. The outer interrupter ring has 18 evenly spaced blades and windows. The 18X reference signal produces 18 ON-OFF pulses per crankshaft revolution. The inner hall-effect switch sends a pulse called the sync signal. The inner interrupter ring has 3 unevenly spaced blades and windows of different widths. The sync signal produces 3 different length ON-OFF pulses per crankshaft revolution. When the sync interrupter ring window is between the magnet and the inner switch, the magnetic field will cause the sync hall-effect switch to ground the supplied voltage from the ICM. The 18X interrupter ring and the hall-effect switch react similarly.