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I just replaced my iPhone 8 Plus screen, no every time I go to my phone after it has sat locked the screen is dimmed all the way to the lowest and I always have to turn the brightness up. I even took the new screen off and checked all the connections. Also I checked all the auto brightness settings. Any help is greatly appreciated!
You may have to buy a tool to copy the serial code from the old screen onto the new one, if you still have the old screen.
Maybe you havent transfer the filter from broken screen to new screen, the filter for proximity sensor. Or you can test this by stick a piece of tape on your new screen and colored this with a waterproof marker to make tape darker ( after the test you can easely take away the tape) so the sensor get less light.
