Ignition System - HITACHI (4WD): Description
The Hitachi electronic distributor consists of a housing, shaft assembly, rotor, and distributor cap. A reluctor, mounted on upper end of distributor shaft, combines with the stator and pick-up coil to provide ignition timing.
Distributor reluctor rotates past the stator. As each tooth of the reluctor approaches and passes the stator, a signal is sent to the ignition control unit. In response to the signal, the control unit then turns the primary circuit in the ignition coil on and off.
This causes a build-up and collapse of a magnetic field in the coil, resulting in a high voltage surge in the coil's secondary circuit. This fires the spark plugs.