Hi everyone, I have a 17" MacBook Pro model number A1229 that I'm trying to fix up for my grandpa to use. When I initially bought it, it had a bad display backlight then as well so I replaced the display inverter board. No luck in fixing the issue. Then I replaced the entire display assembly and still the display is not backlit. I can see the image if I shine a flashlight on it and it outputs to an external monitor. Yet replacing the inverter board and display did not fix this issue. What's going on?