Hi Peter I have a Macbook air that has the same issues. It looks that also have the same issues, with out the corrosion. and i have no idea where to start checking. please note that, 1. it works IF you let the battery drain to 0. If you do, the computer works perfect. One all is done, and charge it can be used. once is you turn of the air, it does not turn on. It have to press the turn on bottom of 6 to 10 set to boot it up, and the cpu is up to 90% to 100%. it show water marks in red, but no corrosions. Where i can start checking the board.