I have a 2005 E55 with the stock command unit up front. I got in the car one morning and everything was fine I turned my head unit on from the power button and could not get it to turn on. The only thing that happens is the Mercedes logo pops up as it looks to boot and then shuts down. Some of the info that I have gathered said that the system is all tied together with fiber optics and if one part it bad it takes down the entire system.

I have also check all the fuses up front and in the rear. So if anyone has some kind of troubleshooting guide that can help I would greatly appreciate it. I have looked everywhere and come up with nothing.

 

Check main battery in trunk if fine; check battery control module if fine; check MOST modules starting with minimum configuration COMAND & audio gateway only (AGW) using bridge part # 0005454484 ($5 or so) then loop in single modules until defective device is found. Check PM.

 

PM replyed, I have the Bridge part I ordered it and picked it up. I just need the guide on how to go about locating and testing all the modules. Thanks for your help.

 

I am experiencing the same thing on a 04 e320 4matic wagon...I'll be watching your thread and if I have anything to share I'll pass it along...