Hello Guru’s,
New member so please correct me if I get anything wrong.

I have a late 2004 MB E270 CDi Avant-garde W211
The other day I was listening to an MP3 CD in the CD changer
When suddenly it froze…I left on for about 30 second but still no movement from the song.
I then turned off the COMAND unit off and turned back on…
But now all that happens now is the MB logo appears on screen for about 5 seconds (also I can hear a burr burr burr sound coming for the CDC) and then switches off
I can’t even bring the CDC out by pressing the little button under the hazard light switch.

Is there any way I can reset the COMAND unit (if this is a possible fix)?
Or
Is there some way to bring out the CDC manually?
Any suggestions would be deeply appreciated.

Thanks in advance.
Jem

This behaviour means that something on the fibre optic network (of audio devices, called MOST bus) has failed.

As you have a W211 with COMAND, it has atleast the following
COMAND
AGW (amplifier/tuner) (in the boot between inner and outer wings on left
NAV processor (in boot)
CDC (below COMAND)
And possibly
Phone
Linguatronic (VCS)
Harmon Kardon version of the AGW

Finding out what has failed really requires a visit to the MB dealer or a specialist with Star Diagnosis AND the knowledge to diagnose MOST bus fault.
- Those without the specialist knowledge (including MB dealers) often do a 'change that item and see if it fixes it' - fine under warranty, but expensive and unnecessary otherwise - it is highly unlikely more than one unit has failed. Unless is the AGW or the COMAND the dealer should be able to bypass the failed unit before changing it and prove the system works (obviously you'll lose the functionality of that unit)

You can PM (private message) alfie on here, he is in Surrey, UK and will be able to do the diagnosis for you properly if you're anywhere near.

Richard

__________________
Of course i'll take it apart.

www.mercupgrades.com
http://www.comandonline.co.uk