I was driving the other day and all of a sudden all of my options malfunctioned. The warning messages for the ABS, EPS, Parking assist, blind spot assist etc. all came on one after the other, then the COMAND screen shows a message saying " please restart the engine or COMAND will shut down in 3 seconds." Mind you I was driving at the time, so eventually it went black and the red battery symbol popped up. I assumed it may have been the batteries, so I had them both replaced. As I am driving along again, the same thing happens. The car basically feels as if you are driving through quicksand. I luckily was close to home and made it into my garage. After ding some research, I was wondering if anyone else had the same issue and was it the Altenator or something else? I heard people mention the SAM control module in some of the other blogs. Any insight is appreciated. Thanks.

I would first check all fluid levels and check for leaks underneath the engine before to restart , if all is well,have (someone with) Xentry to read codes..

I had one system come up and do that and I went to the dealer and they found nothing. Hopefully next time it happens I will be near a Tech Workstation.

If you do not have anyone near you with a XENTRY/DAS laptop, then the dealer is the only option to get the alarm codes and potential solution.

Thanks for the info. I forgot to mention that the car shut down and I had to jump it, which is why I replaced the batteries.

I had the same two months ago - alternator was died for sure. After restart it worked for a while then drained battery and stop the car at all.

Did you check the alternator for proper charging? When the voltage drops, systems will start shutting themselves down to protect them.

My alternator fault was strange - it shows on display (enter to service menu Hold button and left OK) that charging on 12,5-14,2 (never 14,4) and sometimes immediately drops till 11.0 > 10.0 below this value Merc was shut down on the middle of street in seconds
I thinking alternator had short inside. Replaced to new one and charging ALWAYS is 14,4V

So it was the Altenator. My father and I replaced the alternator and now the car runs great. I purchased an aftermarket one from NAPA auto parts for $400, considerably less than the $1400 Mercedes charges for theirs. Accessing the Altenator is somewhat of a nightmare, but we struggled through it. We ended up having to remove the radiator fan and the air filter connection in order to be able to actually remove the unit. I can understand why the dealerships charge so much to do the job. It took us almost 8 hours to complete, but some of the time was just figuring out how to approach aspects of the job.

Great that you have it sorted !
When my alternator died I took car to workshop (starters and alternators specialist). They sold me renewed alternator and replaced it for 250$ in total (alternator + replacement and collected old alternator). Job took 2hrs - mechanic disconnected rear battery, removed radiator and replaced alternator). They offered 1 year warranty on the device with no mileage limit.

Manieks500, wow, only $250? Where are you located? I would have paid that just to save my efforts.

We have some good rebuilt alternators next time. Parts catalog. Glad you found the issue!

-Luccia

Location: Eu -> Poland -> Piaseczno Little bit far from US..