Heated seat not working. What's the cause and how do I verify/fix the problem? on 2002 Mercedes-Benz E320

I'd like to repair it my self if possible. I just need some help in figuring out what the problem is. I don't have a fuse list to check if its a blown fuse and I can't find anything helpful in my operators manual.

Thanks for your help!

If the switch light lights when pressed the element in the seats done ,
Need to take seat out replace , i would goggle it and try to get on mercedes forum to get info...