Hi,
How i fixed the error 14.
My iPhone 5s had glass cracked. I changed the class, restore the phone it was all working just great. I put the plate on the LCD cables, put all the screws back and it was not starting no longer. After i read the review from u guys i tried removing the plate from the LCD plugs on the main board but it wasn't working from a PC so i tried on a mack where, surprise.....it was working and i got back to the start.
So for me was working removing the plate and the screws and restore it from a mack computer.
Hope u fix yours like i fixed mine.
Thanks for the reviews that helped me and sorry for my English :)