I have a W209, 2007 CLK 550 convertible, and the sound system started coming and going, and then it completely went out. I am noticing that when I pull the fiber optic cable from the CD changer, Im not seeing any light coming out of it.

I tried to check all the fuses I believed were associated with the fiber optic loop, 26 and 64, as well as 40 44 10 13 16. What I noticed was that fuse number 13 seems to blow as soon as I turn the car on?

What does fuse 13 go to? and is there a wiring diagram that could maybe help me trace it out.

 

I think it's for the multi-contour seats, parktronic, and linguitronic (voice control). If you don't have any of those items, then I suspect a short somewhere in the wiring.