Charging circuit has damaged in oneplus one

Hi. I have accidentally short circuited my Oneplus one and its not charging normally now. It only charges when turned off at 500 mA. And when I connect it to pc, pc is not recognizes it. I have replaced USB dock connector flex cable. But nothing changed. I think damage is on motherboard, but I dont know exactly which part of it. As pc not recognizes it, damaged part should be related to 2nd and 3rd pin of USB port. Can you please tell me which parts can be damaged in short circuit and how to FixIt? Thanks