Starter Motor: Description and Operation

Starter Motor (Typical):

The Pass-Key II (R) system is designed to prevent the engine from starting if the proper resistance in not sensed from the ignition key. If the correct resistance value is sensed when the ignition switch is in the "RUN" position, the Body Control Module (BCM) will ground the starter enable circuit and output the fuel enable signal. This will allow the starter enable relay to send battery voltage to the starter solenoid switch. The starter solenoid switch will move the starter shift lever, causing the starter drive pinion to engage the flywheel ring gear. After engagement, the starter solenoid switch will close the main contacts, which results in cranking of the engine. When the engine starts, pinion overrun protects the armature from excessive speed until the switch is opened, at which time the solenoid switch plunger spring causes the pinion to disengage. To prevent excessive overrun, the ignition switch should be opened immediately when the engine starts.