PLEASE HELP! Post-logic board replacement, having issues.

[GraphikGeek]

Hey MacBook gurus.. Ready for a puzzle? So, here's the story. My buddy spilled coffee on his computer, it "turned off immediately," but I had him do a hard shut down anyways to be safe. We drained everything out, and dried everything off. Apparently he tried to turn it on again (against my recommendations), but nothing happened. I took it home and took it apart, cleaned the logic board, keyboard, and everything else I could get to. Still nothing. So I told him his logic board was most likely fried. Replaced the logic board, MagSafe board, keyboard, battery, and RAM. Now I get the prohibited sign (picture attached), and it wont boot past that screen. Here is a summary:

1.) New logic board, battery, RAM, keyboard, MagSafe board
2.) hard drive works (plugged it into my computer, and it booted up fine)
3.) keyboard still isn't lighting up, and doesn't appear to respond to any button prompts
4.) will NOT even turn on unless connected to MagSafe (can remove the battery and get the same effect)
5.) battery "indicator" on the side of the computer isn't registering a battery
6.) still get same screen with boot disc inserted

I think that is it.. Please, anyone have any suggestions!? I'm stumped here.

 

[GraphikGeek]

UPDATE! Was able to boot the computer using the OSX boot CD. So it appears as though it isn't recognizing the startup in the hard drive. However, when I plugged the hard drive into my other macbook, it worked fine.

 

[JPNFRK7]

May be coincidental, but the hard drive cable is known to go out on certain year MBP (especially the 2012s).

 

[GraphikGeek]

Thank you JPN, I bought a new HD cable, and it didnt change anything. I was able to boot it with the boot CD, and tried to reinstall a fresh OSX, but it wont let me. I'm stumped.

 

[DarkSel]

Why would you connect a perfectly good logic board to water damaged components? I reckon you probably killed some components hence the issues you are seeing. Hard for me to say what's wrong without testing with a multimeter.

 

[GraphikGeek]

@DarkSel All the components were completely fine on their own. Tested them all. What component, if damaged, could cause the prohibitory sign?

 

[DarkSel]

@DarkSel All the components were completely fine on their own. Tested them all. What component, if damaged, could cause the prohibitory sign?

My suspicion is the Airport card or display still had liquid, shorting out your new board once you connected them. Try testing with just the logic board, some RAM, a known good HDD and an external display connected. If you still have problems, I suspect either you killed your logic board, or it already came DOA.

 

[GraphikGeek]

The display and internet work fine, though. And I checked everything else on another computer, and they all worked. I didnt replace the logic board for a good week after the spill, and I had already taken the computer apart and cleaned the whole thing. Do you still think there could have been a short somewhere?