When the ignition switch is turned to the ON or START position, B+ voltage is applied to coil side of the CRANK relay. When the ignition switch is turned to the START position, the ignition switch sends a B+ voltage signal to the Powertrain Control Module (PCM) crank signal input. The PCM also verifies through the Body Control Module (BCM) that the PASSLOCK theft deterrent system has enabled the engine to start. The PCM then grounds the control circuit of the CRANK relay. When the CRANK relay is energized, it allows voltage to the starter solenoid terminal S.

When voltage is applied to the starter solenoid terminal S, 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 pull in and hold in the plunger, which moves the shift lever. This action causes the starter drive assembly to rotate as it engages with the flywheel ring gear on the engine. At the same time, the plunger closes the solenoid switch contacts in the starter solenoid. Full battery voltage is applied directly to the starter motor, which cranks the engine.

When the solenoid switch contacts close, voltage is no longer applied through the pull-in winding, as battery voltage is applied to both ends of the windings. The hold-in winding remains energized, and its magnetic field is strong enough to hold the plunger, shift lever, drive assembly and solenoid switch contacts in place to continue cranking the engine.

When the ignition switch is released from the START position, the CRANK relay opens and battery voltage is removed from the starter solenoid terminal S. Current flows from the motor contacts through both windings to the ground at the end of the hold in winding. However, the direction of the current flow though the pull in windings is now opposite the direction of the current flow when the windings was first energized. The magnetic fields of the pull-in and hold-in windings now oppose one another. This action of the windings, along with the help of the return spring, causes the starter drive assembly to disengage and the solenoid switch contacts to open simultaneously. As soon as the contacts open, the starter circuit is turned off.