Ignition System - LUCAS Electronic: Operation

As distributor shaft turns, reluctor turns with it. Refer to Figure. As each of the 12 teeth pass across the pick-up coil's pole piece, the magnetic field strength around the pick-up winding is intensified. This creates a voltage in pick-up coil winding.

The rise and fall of this voltage is sensed by the amplifier module, which then sends a signal cutting off voltage to the primary circuit of the ignition coil. This causes a voltage surge in the secondary, firing the spark plugs at the proper time.