I came here looking for a solution, this is what i found normally when you drop the console, wifi module gets unplugged (that piece besides slot-1 with a little gray foam on it), that causes the console to go black screen when turned on showing green led light so how do you solve it? just plug it back, push it firmly and there you go... BUT!! in my case, the console was turned on many times testing it (not mine btw) so the wifi module got damaged. I replaced the wifi module with an old one i had from some DS junk and it worked again. that's it