Chosen Solution
Spilled a few drops of water on MacBook Air. Screen is dim but working (I have to shine a flashlight on it to see it). Works fine on external monitor. Took it apart and found nothing. All cables, etc. are seated fine, good continuity on ‘P’ fuse for backlight and no corrosion anywhere. Apple on back of MacBook no longer lights up. Would seem odd to be the logic board since the drops of water were on the power button side of the keyboard. Any ideas? I’ve done all the PRAM resets, etc. listed in the solutions here but nothing is working so it must be a problem I can’t see.
The display cable and the backlight logic are right under the power button! Remember when you are looking from the bottom (left) you are in truth looking on the tops right side. You’ll need to check the backlight MOSFET and its support logic. Do you know how to use a DVM?
I suspect you have either a bad solder joint or the chip is blown Q7706 (FDC638APZ)
