Chosen Solution
Hello, Just looking into an iPhone 6 and the device boots and behaves normally, it draws between 0.08mA and 0.50mA. It changes the battery icon when the cable is plugged in. Tried 3 computers, 2 different cables and 2 connector ports - same results. I would typically suspect U2 if it was drawing 0.00mA. From reading, Tigris is the element that deals with USB communication. The voltages around this area are ok, theres a 1.8V, VCC_Main, USB5V0. none of the caps around here read anything different when normal. The USB connector on the board itself is physically clean enough. Before going ahead with a U2 swap I am wanting to know is it best to swap Tigris first because to me this seems like the most likely culprit. Thank you :)
Although I doubted if the U2 was even the issue because power was getting inside the phone, replacing the Tristar IC did the trick. I usually like to refer to STS Telecom for this fault, they have a good video that I refer to if I need it: https://www.youtube.com/watch?v=XLFkvPA_… Problem fixed!