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Ignition Hall Effect Sensor: Description and Operation

Hall Effect Distributor:




Hall Effect Pickup Assembly:







Location

Pick-up mounted on distributor plate.

Purpose

PCM uses sensor input to determine engine speed and cylinder identification, and synchronizes fuel injection accordingly.

Operation

Hall-Effect pick-up generates pulses when shutter blades interrupt magnetic field.

Theory

Shutter contains four blades, one for each cylinder. Hall effect switch mounted opposite a magnet.

When a shutter passes between Hall effect switch and magnet it interrupts magnetic field.

Hall effect switch turns OFF until shutter passes, and magnetic field is sensed, then switch is turned ON.

Turning Hall Effect switch ON and OFF generates voltage pulses which are sensed by PCM.

Note: If PCM does not sense input from Hall Effect pick-up, controller will deactivate ASD and fuel pump relay, interrupting voltage to fuel pump, fuel injectors, and ignition coil, (no start condition).