I have NO audio in my car. My navigation works, the radio and cd player "look" like they work. I'm getting a message, however, stating that the phone is not available and the satellite radio is not available. All signs pointing to a fuse being out. Or more than one? I've located all the fuse boxes but the one in the rear trunk's fuses seem glued in. Is there a special tool I need to try to replace myself. Our local Mercedes dealer won't even try to walk me through it. They just want an appt. HELP!!! I am totally capable of replacing fuses and have done so previously but in a different location.