Question 13inch late 2011 MacBook pro does not show signs of life other than green charging light on the side.

[palmsaresweaty]

I recently got a late 2011 MacBook pro 13inch and it does not turn on at all.
I checked the motherboard and there appears to be nothing wrong other than a tiny amount of corrosion near the Ethernet port.
Does anybody know what could be wrong with it?
The charger does work by the way.