Is your MacBook screen very dim/dark? It’s likely a backlight issue.
Is your MacBook LCD too dark even when you put it up to full brightness? If you press a flashlight against the white Apple logo (in the back of the silver cover) do you see something on your screen? If you do, it is a backlight problem and it is 100% fixable. Please note that the flashlight troubleshooting method does not work if you have the latest models where the white Apple logo has been removed and replaced by a shiny logo; for those models, flash the light on the screen directly and angle the screen at about 45 degrees until you see something. If you do see something it means it is indeed the backlight.
Over the years we have fixed many backlight issues and we can say with confidence that it is 100% fixable, no matter how bad it is. There is no need to replace the entire logic board.
The backlight problem is very common with liquid damage particularly if the liquid entered from the back of the MacBook, very often unnoticed by most users until the backlight is gone. No worries, we can fix it and we can undo it!