iPod classic 3rd gen won't turn on

Hello,

I have an old 20 gig 3rd gen iPod with a click wheel (the only one with the buttons between the screen and the click wheel). It won't turn on. I have heard that it could be the logic board or the battery.

Is there a way to find out?

I have tried to plug it in to power and nothing. It hasn't been used or powered on for over a year.