Lesson3/Learning Event 3
DESCRIBE THE PRINCIPLES, OPERATION, AND CONSTRUCTION OF SOLID-STATE
The recent rise of electronic ignition systems is due to the superiority of electronic ignition over
conventional ignition systems in several major areas. These systems totally remove one area of
maintenance from the ignition system, that of the ignition (contact) points. Also, because the
electronic ignition system produces a higher voltage than the conventional system, the electronic
ignition system usually can fire a fouled spark plug. In the area of high performance, the electronic
ignition system is far superior in that its voltage does not deteriorate as quickly at high engine
speeds as the conventional ignition system. Because the electronic ignition system does not contain
ignition points that wear, ignition performance does not deteriorate with mileage.
The electronic ignition system differs from that of a conventional ignition system in that it consists
of a special pulse sending distributor, an electronic control unit, a two-element ballast resistor, and a
special ignition coil. Also, the ignition breaker points and capacitor used in conventional ignition
systems have been replaced by a gear-like piece called a reluctor and a pickup unit. The reluctor
replaces the distributor cam used in the conventional distributor. The pickup unit is made up of a
permanent magnet, a pole piece, and the coil.
The ignition primary circuit is connected from the battery, through the ignition switch, through the
primary side of the ignition coil, to the control unit where it is grounded. The secondary circuit is
the same as in the conventional ignition system. The magnetic pulse distributor also is connected
to the control unit.