Display is dim and will not brighten
The image on the display of my MacBook Pro A1278 is very dim. I'm not sure but I don't think that it's the backlight since the image is visible enough that the laptop can still be used but the screen lighting is very dim. The brightness adjustment on the F1 and F2 keys do nothing when either one of them is held down. The brightness adjustment in the System Preferences doesn't do a thing to dim or brighten the screen image. Is this a common problem and is there a fix for this problem.