Distributor: Description and Operation

DESCRIPTION AND OPERATION

NOTE: The distributor is serviced as an assembly only, except for the distributor stator.

The universal distributor operates and is installed as follows:
1. A Hall effect vane switch assembly (distributor stator) signals the ignition coil to be switched OFF and ON by the Powertrain Control Module (PCM) and Ignition Control Module (ICM).

Hall Effect Device:

2. The vane switch is an encapsulated package consisting of a Hall sensor on one side and a permanent magnet on the other side.

Rotary Vane Cup:

3. A rotary vane cup, of ferrous metal, is used to trigger the signal OFF or ON.

Figure 7 - Magnetic Flux Field:

4. When the window of the vane cup is between the magnet and the Hall effect device, a magnetic flux field is completed from the magnet through the Hall effect device and back to the magnet.

Hall Effect Device Response To Vane:

5. As the vane passes through this opening, the flux lines are shunted through the vane and back to the magnet. During this time, a voltage is produced as the vane passes through the opening.
6. When the vane clears the opening, the window edge causes the signal to change to zero volts. This signal is used by the PCM for crankshaft position sensing. The computation of the desired spark advance is based on engine demand and calibration.
7. The conditioned spark advance and voltage distribution is accomplished with a conventional distributor rotor, distributor cap, and ignition wires.