Ignition Hall Effect Sensor: Description and Operation

Hall Effect Distributor:

Hall Effect Pickup Assembly:

LOCATION

Sensor (pick-up), mounted on distributor plate.

PURPOSE

Powertrain Control Module (PCM) uses sensor input to determine engine speed and cylinder identification, and synchronizes fuel injection accordingly.

OPERATION

Pick-up generates pulses when shutter blades interrupt magnetic field in pick-up.

THEORY

Hall effect switch is mounted opposite a magnet.

A shutter wheel, containing four shutters, (one for each cylinder), passes between Hall effect switch and magnet.

When a shutter interrupts magnetic field, the switch turns OFF. When the shutter passes, the magnetic field is sensed, and the switch is turned ON.

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

If the PCM does not sense input from the Hall Effect pick-up, PCM will deactivate Auto Shutdown ASD and fuel pump relays. This interrupts voltage to the fuel pump, fuel injectors, and ignition coil, (no start condition).