If you want to troubleshoot the problem when you do a repair connect the screen to the iPhone without bending anything and power on the device. If everything works fine then install it properly. If after the installation something is wrong than you have 2 options. 1-You didnt bend the flex cable at the right spot or bent it too much which just broke your screen. 2-One of the 2 connectors (LCD/DIGITIZERS)have popped out of its socket and needs to be reconnected. When doing so make sure that everything is in place before installing the magnetic shield, on the iPhone 5s the connection doesnt seem as solid as on previous models (personal experience)