iPhone 4 will charge in wall, but won't sync or charge via USB
I know, in most cases, this problem to be the usb port on the iphone. Unfortunately this part seems to be a part which only one in five of these parts to be good from experience. Either the mic or data port are defective which makes a diy repair frustrating. Most people will change it once they hit a defect part and give up. Don't give up. Trying to help people who are frustrated as I was. Usually occurs when you update with a port having bad contacts and ends up with a no sync or no voice on phone mic. May not be what you want to hear.