The starting system includes the battery, starter motor, solenoid, ignition switch, circuit protection and wiring connecting the components. An inhibitor switch is included in the starting system to prevent the vehicle from being started with the vehicle in gear.
When the ignition key is turned to the START position, current flows and energizes the starter's solenoid coil. The solenoid plunger and clutch shift lever are activated, and the clutch pinion engages the ring gear on the flywheel. The switch contacts close and the starter cranks the engine until it starts. To prevent damage caused by excessive starter armature rotation when the engine starts, the starter incorporates an over-running clutch in the pinion gear.
Vehicles with a manual transaxle are equipped with a clutch pedal switch in the starter circuit, which is designed to prevent the starter motor from operating unless the clutch pedal is depressed. Vehicles equipped with automatic transaxles use a Park/Neutral position switch in the starter circuit. These switches prevent the starter motor from functioning unless the transmission range selector lever is in Neutral ( N ) or Park ( P ).
Heavy cables, connectors and switches are utilized by the starting system because of the large amount of amperage this system is required to handle while cranking the engine. For premium starter motor function, the resistance in the starting system must be kept to an absolute minimum.
A discharged or faulty battery, loose or corroded connections, or partially broken cables will result in slower-than-normal cranking speeds. The amount of damage evident may even prevent the starter motor from rotating the engine at all.