how does the alternator work? I need details ASAP. Does it work harder at night since there are lights at night and what are the things it powers and give details please.


Asked by Apr 03, 2014 at 02:14 PM

Question type: General

1 Answer


The alternator is designed to maintain the charge in your battery, that is it's main function but it will supply voltage to the entire electrical system of your car while it is running down the road, ie. headlights, brake lights, turn signals, engine controls anything electrical. Newer vehicles have alternators that can deliver over 100 amps of power but only intermittently, at full load they will burn out, that is why a good battery is so critical in today's vehicles due to high current loads of today's cars. So your alternator will charge high just after you start your engine to replenish the battery then drop back, it wil vary amperage and voltage outputs as you drive depending on demand, so yes it will work a little harder when everything it turned on like heater, lights etc. most alternators in 12 volt vehicles run between 13.8 to 14.2 volts. It is a good idea to have your charging system checked at least once a year, sometimes it can pick up on a problem before it becomes a real headache. Hope this helps.

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