Starting System: Description and Operation
CIRCUIT OPERATIONSTARTER
When the Ignition Switch is moved to the START position, battery voltage is supplied to the Starter Solenoid through the PPL (6) wire. Both solenoid windings are energized. The circuit through the Pull-In Winding is completed to ground through the Starter Motor. The windings work together magnetically to close the Motor contacts. Full battery voltage is supplied through the Motor contacts to the Starter Motor, cranking the engine.
As soon as the Motor contacts close, voltage is no longer supplied through the Pull-In Windings, since battery voltage is supplied to both ends of the windings. The Hold-In Winding remains energized, and its magnetic field is strong enough to hold the Motor contacts closed and permit the Starter Motor to continue cranking the engine.
When the Ignition Switch is released from the START position, battery voltage is removed from the PPL (6) wire and the Junction of the two windings. Voltage is supplied from the Motor contacts through both windings to ground at the end of the Hold-In Winding. However, the voltage supplied to the Pull-In Winding is now opposing the voltage supplied when the winding was first energized. The magnetic fields of the Pull-In and Hold-In Windings now oppose one another. This action of the windings causes the Motor contacts to open. As soon as the contacts open, the starter circuit is turned off.