Chosen Solution
Here is the problem: If I leave the phone for a couple of minutes with locked screen and then unlock it the screen brightness is normal but if I do something on it the after 2-3 minutes the screen goes very dark. Also the auto brightness is not working. What can be the problem? Maybe temperature sensor or proximity? Update (05/14/2016) The CPU is getting extremely hot and the screen starts dimming. When I try to put my thumb on the CPU to get it cooler the screen is getting back with normal light. Any help about what can cause CPU overheating?
if the screen replaced recently, you can check if the black tape is still on the blacklight contacts. if not maybe that’s your problem, because this could in fact create a short circuit and make the phone really hot.
Sounds like a proximity sensor. Was the screen replaced recently? If so sound like you need to replace the front camera assembly.
The black tape is all right. It is properly placed. Other strange thing I have noticed is that when I plug in the phone on the charging cable the screen goes lighter and the cpu doesn’t gets hot that much. Is there a possibility the battery can cause this hotting issue?
Hi, Have something somewhat similar. Iphone 6. Phone was dropped and screen went dark. Phone still answers and connects to itunes. Noticed that in very bright sunlight, I can faintly see the screen and operate it. However, it is very faint and appears to be totally blank in normal light. Re-seated the 4 cables from screen but no change. Think it is the screen? Or possibly proximity sensor? Or something else to check based on phone being jarred? Thanks in advance for any pointers.