Chosen Solution
after doing a screen replacement on my 6s as per youtube instructional video, i cheked display/screen before fitting to phone body. as soon as i snap the new scrren together with phone body i lose my display. what have i done wrong or have i inadvertently damaged something is the process of replacing my screen ?
It sounds like you have a bad quality screen and is shorting out. Check that the screen is not shorting against anything.
Try also disconnecting the home key at the bottom. it could also be the Middle flex that runs up the rear of the screen
