First thing when a piece of gear won't turn on: is it plugged in? I don't want to come across as though I'm insulting your intelligence, but you'd be amazed how often that turns out to be the problem. But I'll assume you've already checked this.
Next is to check the fuse. I assume you've already done this, too.
If so, next is to open it up, if you know what you;re doing, or take it to the shop.