Ive got a c55 and it's got the button for satellite radio but it is not activated. How do I activate it with sirius radio? Do i have to go back to mb? do i just sign up for sirius? Thanks alot.

First, you have to have the radio itself installed. Then an antenna has to be mounted. Finally you simply call Sirius and you get over a year of free service.
WARNING: I had the antenna installed in the rear deck lid in my brand new C55. There is an extra charge for this stealth procedure.
Reception is iffy and am having the dealer change it to a roof mount. The clean "no see" install is fabulous until you challenge the Sirius even a little bit. It is truly disappointing that MB put enough attention on Audio to integrate an excellent sat radio into the car and then totally dropped the ball on engineering a discreet antenna to finish the job.

Generally, you just go to channel 1 and follow the instructions or call the toll free number

I am activating mine and for some reason when I go to the "SAT" screen there are not any options that I can choose. It does not allow me to go to any channels.

All it says is the phone number to call and my ESN number. Any feedback? We are having issues activating this head unit.

Hey Quickvr4, Did you ever solve your issue? Having the same problem with my 08 C300.

Hi Silver -

If you have any questions about your SiriusXM radio, feel free to reach our Digital Care team by filling out this form.

https://listenercare.siriusxm.com/app/digital_ask/incidents.c$social_media/638

We'll be in touch at your earliest convenience.

Thanks,
Jess
SiriusXM Digital Care Team

Talked to customer care. The issue is with Sirius on their end for our cars. They need to reset our account/Radio Id on their end. Give them a call at: 888-463-5435