Hi all, I have done some search on the treads but I cant seem to find any solutions, I have a 2008 W211 E63 that the radio only turns manually and it is not communicating with the steering column, and after a while it says turn on the engine or the radio will shut off.

On the steering column I cant see the radio, navigation, or telephone, or control the radio up/down. The car has a brand new battery, alternator is good, all the fuses related to the command + radio are good, the CD changer does not open either. what else can I check. I don't want to by a new head unit when it could be something else that I could do.

Thank you in advance,

 

Has anyone been doing work in your dash or was the radio pulled recently for any reason? Sounds like your connection to the canbus is broken somewhere.. If you're lucky it's just a broken wire.

If I remember correctly the head unit connection to canbus happens off to the lower right from the head unit: far upper left of the passenger footwell. You can check for continuity between that hub and the wiring going into the back of the head unit. I can't recall exactly how much voltage you should have on can+ and can-, but there are a couple head unit install threads here that have that information if you search.

 

nobody has work on the radio but they where working on the back of the car does this cable runs to the back?

 

Back exterior or back in the trunk somewhere? The canbus network runs all over the car, but really hard to say without knowing details. There were a few different connections for the comand unit depending on where you are in the world, the most common US connection was a single plug in the back of the comand with power, canbus and fiber for the MOST fiber ring. If you have this connection then your canbus is made in the passenger footwell.

There is another part that could be affecting you: everything on the fiber ring needs to be alive and working or other things won't work correctly. If they were working in the lefthand side of the trunk where the audio gateway is or the GPS unit, and one of those fiber connections got damaged or didn't get reconnected that could cause some issues like this.

 

thank you, I will double check the back connections, thank you, for taking the time to respond,

 

Absolutely correct, if a component is part of the MOST ring, it should be powered, else the ring fails. I also found out that behavior when the Comand refused to start after pulling a fuse for the Voice Control System (after disabling this in the computer).

 

So finally I had the time to open up the trunk, and I found the these two optical cables, in that module, only one of them shows the red light.



plug it only one has the red light the other show nothing,.

 

Buy this (https://a.co/d/9qW8Meq) and put it on that connector in your hand, it should carry the signal forward and bypass that module. If the radio functions normally you could leave it bypassed or replace that module, not sure exactly which one that is but maybe phone?

 

Thank you, will try it,