StephenK

In my 06 SL600 today when starting the car the command unit comes on, but then instead of showing anything, like a radio station or CD or Map, a small message comes on and says "DEVICE UNAVAILABLE" and then the unit shuts off.

In the past after leaving the car sit for several days I would get a message in the instrument cluster saying convenience items unavailable, but then after running the car for a few minutes that would go away and items like the steering wheel moving up and down would work again.

Any ideas????

Murtaza

It could be your battery/alternator.

My car died a couple weeks ago and right before it did, I got that message. My alternator was out...

StephenK

Just went out to run some errands, got in the car, started it up and the command unit was up and running, noticed the clock on the dash was working too. Maybe the convenience battery was low, not sure, but oh well for now it is working again.

Scotsman

I've had the "convenience functions temporarily unavailable" quite a few times but never "DEVICE UNAVAILABLE" and shutting down. COMAND was always available. Doesn't sound like the same thing to me.
If it happens again try your heated seat - if the led's on the seat switch flash the battery's low. That's what happens when I get "convenience functions temporarily unavailable".

MBELITE

when battery voltage gets low the car will go into proitization (sp) and consumers will go offline.. if your having comand problems that can be a whole diferent story. you may have a problem with your fiber optics or the MOST RING.

BMS

Had dealer install Mercedes trickle charger in trunk so that all I have to do is plug it into wall when the car sits more than a day or two and it ended those kinds of problems

trident-7

My 3 year old SL500 with 11,000 miles on the clock comes up with "Convenience functions temporarily unavailable" whenever the car is left more than 18 hours without a drive. Within 5 miles the battery recharges so it all kicks back in again. If I leave it a week, you even have to use the metal bit of the key to get into the car.

I took it to Mercedes Benz main dealers 2 weeks ago thinking they would fit a new battery but was told that they had detected a drain on the battery but didn't know where it was coming from. (They thought it might be a fault with the EIS, or maybe with the immobiliser)

I took it back in for further tests this week and was then told that they could not detect any fault, and that the battery was fine, and that they had just recharged the battery and that everything should now be fine.

2 days later the "convenience functions-----etc" is coming back on again.

Any ideas what is going on?

Scotsman

I had the exact same problem. Found out it was the telephone wiring. It was draining the battery even with no phone connected.
Only get that warning if the car's not driven for 2 weeks+ now.