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Home> How To> Repair Alternator> What is an Alternator?

What is an Alternator?





The alternator is part of the automotive charging system. The alternator and your battery work together to provide power for all of the electrical components in your car. The alternator is powered by the crankshaft, which converts the energy created by the pistons into a circular motion. The electricity created in the alternator flows through the battery (which keeps your battery charged), providing the voltage necessary to power all the different electrical components in your particular vehicle.


If you look on the back of your alternator you will see a variety of different electrical connections. The S terminal is responsible for measuring battery voltage. The IG terminal is the ignition switch that powers on the voltage regulator. The L terminal closes the circuit to the warning lamp. The B terminal is the primary electrical output that connects to the battery. Finally, the F terminal is a full-field bypass for the regulator.


The failing of cooling fans is a common alternator-related problem that many people experience in their car. The alternator generates a lot of heat when it is functioning properly and it must be cooled down to avoid overheating. There are cooling fans inside the aluminum housing that keep your alternator from getting too hot during normal operation. When these cooling fans break, it is important to get them fixed right away because without the cooling effect from the fans the alternator will overheat and eventually fail.


If your alternator is not working properly, it can cause damage to your entire electrical system. Over time, dirt can build up in the rotors of the alternator and cause the rotors to lock up. Bearing failure is one of the most common problems with older alternators. When your alternator seizes it will destroy your battery. You want to make sure you catch alternator problems early before they wreak havoc on your electrical system. If you think that your cooling fans might be failing, or you hear the rotors in your alternator grinding then you should have the issue examined by a mechanic immediately.. 


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