No display backlight, no warranty, left IO board to blame, options?
I have a Macbook Pro (15", 2008, A1260) that a few weeks ago started showing lines all through the screen. I figured it was nVidia GPU rot, so I sent it off to Apple for free out of warranty replacement of the logic board.
When I got it back from my local Apple Store, the tech informed me that they were "unable to fix the display issues". They gave me back my Macbook with a nice new logic board, complete with a nice line-free image on the display... and no backlight! Come on, that was never the issue, my backlight was always fine!
Well, now Apple refuses to troubleshoot or fix the issue that came up while the machine was in their care unless I pay them over $300. I'm not putting that in to an old machine, so it's left to me.
The first thing I tried was replacing display's LED driver board using the instructions here. Nothing, no backlight. I replaced the whole display with a working unit from another Macbook Pro and that display didn't light up either! I switched back the displays.
Next, I took the left IO board from the working Macbook and placed it in mine. Success! My display lit up! So now I know the issue is somewhere on my left IO board. Nothing happened to it, no liquid spill, no drop. It just broke when I sent it off to Apple to get fixed.
I'm an engineer with experience soldering surface mount components. All the other features on the left IO board seem to be working just fine. Short of replacing the whole board for over a hundred bucks, if there anything I can look at replacing (or shorting if it's unimportant)? Or should I just cut my losses and grab the board I need? Or do I have more power to force Apple to do this for free than I imagine?