Chosen Solution
I just changed my cracked display, I ordered a full assembly kit from iFixit and followed the provided guides. The replacement went smoothly but after fiddling around with the phone I found the next issue: Auto brightness setting is now useless, it doesn’t adjust anything on the screen, everything else works perfectly, front facing camera, speaker, proximity sensor. just this one thing, so, any ideas of what could be happening? Thanks for the advise.
Not a whole lot that could be wrong here. Most likely the flex got tore during install. The fix is a new cable, it shouldn’t be too hard. I suppose it could also be software. Restart your phone by holding power and home. After it boots, check to see if auto brightness is enabled and working. If not, its almost 100% that the flex tore.
The replacement screens iFixit ships are not original Apple products, and the iOS detects this (even if you swap the front camera flex with the original), and the “Auto Brightness” feature is disabled. I had this issue with an iFixit display, and so far there is no solution. Also iFixit has not recognized this problem officialy :(
I know this thread is old. But I have to add that I replaced the pre mounted set of front facing camera and sensor cables with the original ones of the original display unit. Now it works flawlessly! But the button for auto-brightness is still missing, allthough the auto function now works!
