Backlight not working, replaced LED driver board and LCD but no luck

Backlight went out while house was running on generator. Since then, I have replaced the LED driver board (it had burn marks on it) but still didn't have a backlight. I then replaced the LCD but still the same thing. I also replaced the thin cable (the one that you push in), but still no luck. I've tested the power supply and the voltages check out. Any help at this point is greatly appreciated! Thanks