Hall Effect Sensor: Description and Operation

Hall Effect Distributor:

Hall Effect Pickup Assembly:

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

OPERATION
A shutter wheel containing four blades, (one for each cylinder), rotates between the Hall Effect switch and a magnet.

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

- When a shutter blade is between the switch and magnet, it interrupts the magnetic field, turning the switch OFF.

- When the shutter is not between the switch and the magnet, the switch is turned ON.

- Turning the switch ON and OFF generates voltage pulses which are sent to the PCM.

NOTE: If the PCM does not detect pulses from the sensor, the PCM deactivates the Auto Shut Down (ASD) and fuel pump relays, interrupting voltage to the fuel pump, fuel injectors, and ignition coil, (resulting in a no start condition).