I have also fixed 1000s of iphone dating back to 2009 and never once did i have to do that as well but if you kno anything about electronics the hardware was just simply not compatible i tried a different screen and the samething would happen just instead of red it would go blue and so did the original as soon as i restored with original apple parts things work fine customer very happy thank you and i did the restore with the phone open and no emi shield and it still worked