Chosen Solution
So my iphone 6 has a black screen. its unresponsive, nothing at all, but when i plug it in to my pc with usb cable it vibrates 3 times, which i think means that it has to accept the usb cable to pc, which i cannot do sine the screen is black, tried it with several other screens and still not working, changed the battery but thats not fixing it either. So i think the problem lies with the motherboard, but i really cant nothing about microsoldiering, but i have the basic soldiering equipments which i think is not good enough for the micro-work. Any suggestion to what i can do?
This sounds like a backlight issue. Try shinning a torch on the screen and see if it has image. ITunes want recognise it if it is passcode locked, unless it has been connected to the pc recently. If it is the backlight it will need to be repaired by a board level repairer as the backlight IC is close to the CPU Usually they will replace the IC, coil and diode and maybe a fuse or capacitor if they have blown.
The screen is dead but the battery and phone itself is ok this usually happens with water damage
