A couple months ago, when I was on vacation in Mexico I had my iPhone 3gs charging to my wall charger and it was working perfectly fine, when I woke up I realized there was a power surge since there was no electricity, and to my surprise my iPhone was on 12% battery after I had let it charge the whole night, I knew right away something had fried, my first guess was the battery so when I got back home I had the battery replaced and that wasn't the case because the phone was still on low battery,I then thought it might be the USB charging port but I am not sure and I wouldn't want to waste the money replacing it if that's not the problem. I would really appreciate it if someone could help me out, thank you