Originally Posted by wizardknight
There are only two other options. Bad cable or bad system board. I have never heard of a system board with that kind of a problem.
You are not using a case are you? I have seen cases that cover the spot where the light sensor is on the lcd. I had to drill a hole in one once.
Also did you get a new or used lcd. Maybe someone was getting rid of a lcd that worked, but had a bad light sensor.
I am not using a case.
Both replacement LCD/Digitizers were reconditioned. But I think the light sensor is not part of the LCD -- it is on the flex cable, right?
Is it possible that something in the firmware is no longer properly accessing the light sensor? Does it make sense to try to load a different build in before going to another flex cable?
The strange part is that normal screen power function stopped right when the LCD was replaced--that's what makes me think it is hardware and not the firmware. But what would cause a light sensor to all of a sudden stop functioning?
And then again, is it definitely the light sensor which makes the screen power toggle non-functional?