Chosen Solution
I’ve tried everything I could think of or find with this issue. I’ve taken the battery out, I’ve tried it with the SD card taken out, I’ve taken off and put back the wifi card, I feel like I’ve done everything to try and fix it but nothing has worked, and I have two with the same exact issue.
There is a chance there is an issue with the screen itself. Like jayeff said, you can check the screen with a flashlight in a dark room. If there is no visible picture, there might be an issue with the screen and not the backlight. You can try to reseat the screen cables, as they might have come loose and might not be making proper contact. This can happen when the console is taken apart or dropped. All you have to do to reseat them is to unplug them and plug them back in, making sure they are making good contact and are completely attached.