Chosen Solution

Hello iPhone X after replacing the rear glass has stopped working FaceID (the function is temporarily unavailable). I will add that everything was ok before the repair. What I also noticed, you have to wait long enough for the rear / front camera to run. It takes about 10sec. First the black image is displayed and then the view from the camera. The image is sharp and clear. The same happens with the flashlight. You have to wait a little longer until it works. Before the repair everything worked as it should. I checked all the tapes and connections are ok. DFU and soft clean did not help. What can it be fault? Camera? Damage on the motherboard? greetings

It would probably be damage to the motherboard if you used heat or the heat may have fried the front camera. unsure of the front camera.