Black Screen on iPod Touch

About four months ago, my husband left his iPod Touch in his car while at work. When he returned after 10 hours his screen was black. He assumed the battery died but after recharging the Touch, the screen would not appear, it remained black. If its hooked up to the iTunes library everything seems fine. So now four months in...no change. I'm sure the heat (during summer reached 101) fried the screen. We are hoping to take it to Genius to see if there is any hope of saving it.