QuestionI own a 2005 Hyundai Sonata, which I purchased new in June of 2005. Since then, I have had three batteries. The first lasted for 21 months, the second lasted for 27 months, and I just put the third one in yesterday. Every time the battery needs to be replaced, the car completely dies -- and dies suddenly. No warning signs, not even a battery indicator light. In fact, this last time, I drove it in the morning, everything was fine, but after sitting in my garage for four hours, it would not start at all. The dashboard lights flicked for a second and then complete darkness. The only indication of any life at all was the car door "buzzer" was trying to buzz, without much luck. They said my battery was "completely fried". But no one can tell me why, not the dealer and not my mechanic. Alternator and battery charging system checked out fine. All my batteries have been Hyundai batteries.
Answer So that's how Hyundai can sell a good car for a cheap price; they put a crap battery in it. I'm guessing that this car might sit without being driven for several days at a time on a regular basis. The computer in the car is on all of the time, even when the ignition is off. This causes the battery to discharge some every day, then get charged back up when the car is running. But, the charging system will not work if the battery is discharged more than about fifty percent. Charging the battery up and down repeatedly causes sulfate deposits to form on the plates of the battery, and that prevents the plates from reacting with the acid and permitting adequate amperage to flow through the battery. As all of this goes on, one of the cells will get worse than the others and, because it still has to perform up to the same standard as the other cells (there are 6 in a 12 volt battery), it is stressed even more and fails rather suddenly. A battery with one bad cell is no better than a battery with 6 dead cells, it is dead. Now, I know that the car is probably still under that gigundous warranty that Hyundai gives you, and if they're continuing to replace these batteries at THEIR cost, well, you might want to keep going back there. But if you're paying for these batteries yourself, find an independent garage that carries a big brand name battery like Interstate, Delco, Deka, Exide, etc. Buy the battery with the longest warranty that they offer, it is a better battery and will deliver better performance in all weather. Plus, since its' capacity for amperage delivery is much higher than the OE battery (of which the only thing that Hyundai cares about is its' price and hence its' addition to the cost of making and selling the car) you will get a lot more life out of it. If possible, make sure that the car is driven at least twice a week for at least 10 miles or so (a lot of short trips is as hard on the battery as infrequent driving). And keep the warranty papers AND the receipt that come with the new battery, you will need them if it goes bad down the road. Oh, and while you are getting the new battery, get them to check the performance of your charging system, just in case the dealer missed something.
