Backlight problem, it starts off but after a while it turns on

I spilled some juice on my Macbook, but quickly took out the battery and waited till it dried to see if there was serius damage. When I turned it on again, half of the screen was totaly black so I got a little scared, but as it started to load the screen came to life. When the desktop appeared it seemed as tere was no problem at all, my info was still on the hard drive, the speakers worked well, the mouse pad, everything... even the screen was totally iluminated by then. But the problem with the backlight made me decide to turn it off again and wait one more day... so the next day I turned it on again and the same happened, half of the backlight was dead (the display works fine though) but it comes to life as the desktop appears, even so, after a few minutes the backlight died again so I got scared again and turned it off, I made one final try and the same, backlight dead then alive... so basically I think that the display must be fine as it turns on (even if it starts half dead), and also can't be the logic board as EVERYTHING works just fine... so what do you think??

Im scared because Ive heard that changing the display is very expensive, and so is the logic board. Ive already changed it once and it was so painful when I read the cost of it, I dont want it to be that again!! ='( .