Original post by: rdklinc ,
Don't get liquid on the heatsync unless you plan on re-applying thermal paste. Have you booted to an external drive to see if you can wipe the SSD in Disk Utility and do a fresh install? If the SSD is not visible in that scenario I would re-seat it and try again before resorting to cleaning the entire logic board. And even then, I would examine the entire board for corrosion and just remove the corrosion before I arbitrarily starting scrubbing down the whole thing. (I'm assuming you don't have an ultrasonic cleaner.) Personally I use 99% alcohol. 85% alcohol is 15% water....