2002 Hyundai Sonata Automatic 60000 miles. Several times my battery light has come on, and each time I check the battery there would be corrosion and a slight chemical smell and I would clean it off. Then the light will go off. Recently the same thing happened, but when I cleaned the battery this time the light stayed on. I relpaced the battery with a new battery. But the light is still on. A friend says that it's my alternator, and my brother says it's the wiring to the battery or engine. The cost of an alternator job would be about $2,000.00. Can you give me a clue as to what to check next? I do not want to spend money needlessly.
You need a new alternator, when the battery light comes on it really has nothing to do with the battery. The voltage regulator is not toggling to charge which turns the ground to 12v positive thus shutting off the light. Unless you have a wiring issue replacing the alternator you should solve your problem.