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I just replaced the screen in my IPhone 6s Plus, I also replaced the rear camera lens, just the glass part. Now both the front and rear camera won’t work. I did have the battery disconnected and all power drained from the motherboard (I held the power button for 30 Secs.) this has never happened to me before and I have replaced several screens. Thank you for the help!
The flash won’t work if the rear camera doesn’t. The two cameras are on separate flexes so either you accidentally damaged the flexes during the repair or you may have damaged the logic board. Both cameras are driven by the same power rails so if one of them was damaged, then both cameras would fail. Ideally, you need to isolate a variable here. If you have access to known good cameras, then you would see if they are the issue or not.
