If you don't immediately power down and thoroughly dry it out the current flow causes corrosion. Looking at your pictures I THINK I see some blue - can't tell for sure - it isn't sharp enough but I would open it up, power it down (disconnect the battery too) examine the board closely for any corrosion and clean it off very carefully if found. If you aren't comfortable with thatpernaps your friend can help. If you find any you really ought to check the back of theboard and the screen connector too, if you find parts that are damaged you might need to have to get professional assistance if your friend is good at his job he should be able to guide or assist you. I'm nowherebut suspect there's a guide on tearing it down. Good luck if you do find corrosion try alcohol and a soft small toothbrush on it... dry thoroughly before reconnecting the battery and trying it out. With luck cleaning the corrosion will do the trick.