I need to find out how to reset my battery on my iPhone 4
What do you mean "reset my battery"?
What do you mean by reset? If you mean recalibration of the battery meter, then all you need to do is completely drain your battery to 0% or until the phone shut itself off, then charge it to full.
The battery on my iPhone 4 won't charge and I remember "reseting" the battery on my3GS and it then took a charge. I not sure if "reseting" is the right term but the battery won't charge.
If you are still under warranty and your battery does not take any charge, then I would suggest that you take it to the apple store and have them replace the battery. If you are under warranty, they will not charge you for the replacment.
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