Once the solenoid switch contacts close, current stops flowing through the pull-in winding because battery voltage is applied to both ends of the winding. The holding mode winding remains energized, with the electromagnetic field strong enough to hold the plunger, actuator arm, starter drive mechanism, and solenoid switch contacts in place to continue rotating the engine crankshaft. Once the engine starts, the pinion clutch protects the starter motor from overspeeding until the ignition switch is opened.
After the ignition switch is moved from the start position, the starter relay opens and battery voltage is no longer supplied to the starter solenoid. Current flows from the starter contacts through both windings to ground at the end of the pull-in winding. In this case, the direction of current flow through the pull-in winding changes to the opposite of what it was when the winding was first energized. This circumstance, together with the action of the starter return spring, leads to the disconnection of the starter drive and the simultaneous opening of the solenoid switch contacts, as a result of which the starter circuit is de-energized.
When the ignition switch is turned to the start position, a discrete signal is sent to the body control unit, notifying it of the transition to the appropriate ignition mode. The body control unit sends a message to the engine control unit, notifying that the starter has started to rotate the engine crankshaft. The ECM checks the transmission's park/neutral position and, if this condition is met, supplies 12 V to the starter relay control circuit. This causes the battery voltage to be supplied via the starting relay to the starter solenoid
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