no usb detection unable to charge able to boot with charged battery
I got a device from a friend. The device didn´t start at all. Hard Rest......
Then I plugged a charged battery in and it booted to springboard. But the phone does not detect any USB connection. Even in DFU mode, my iMac doesn´t detect the phone. There were 3 missing caps near the battery connector. I replaced these. I checked the voltage on any component that is a need for USB detection and charging but all fine. In my opinion, the error should be caused by U2 chipset, but the voltage supplying this chip is fine and at the right value. Do you have any other ideas what could cause this problem? (no water damage, but he replaced his battery with a very bad third party battery)
Thank you in advance.