Bigglen1

Did anyone ever have any problems caused by an unexpected slight current drain when your w212 was left parked for couple days or more?

The reason why I ask is because this is what Happened to me three times over the last month:


After a few days or a week of sitting unused, When I go to start my car the following happens.
When the engine started, the cooling fan came on full blastand the car does not shift out of park.
The following messages scrolled on the dash:
· SRS Malfunction – Service Required
· Cruise Control inoperable
· Blind Spot Assist Inoperable
· Tire Pressure Monitor Inoperable
· Pre Safe Inoperable
· Lane Keeping Inoperable
· ABS Inoperable
· Traction Control Inoperable
· Front Left Malfunction Inoperable – Service Required
· Front Right Malfunction Inoperable – ServiceRequired
· Power trunk closer does not work
It's going in for diagnosis this weekend.

alanme123

I think this forum had threads about the battery being drained if the car hasn't driven for days. It was an issue that people were having. You can try doing a search on the forum?

Live Oak

For my car, at least, there was a software issue of the AC evaporator drying fan cycle running full time, draining the battery. Intermittent . . .

Normally runs about a half hour? about an hour after parking.

Arrie

All those errors could be from the battery going too low but if you was able to start it then the battery did not go down.

It's probably the power module issue that feeds those devices.

I have left my car parked for three weeks several times and never had any issues. This with both my 2011 E350 that I had and with the current 2010 E550.

PGT

there's a dryer in the HVAC system that is known to fail open (i.e. "on"). I had this issue on my '10 E550 Coupe; the fix was to disconnect it. Its an overbuilt system and not necessary apparently.

Bigglen1

The SAM (Systems Acquisition Module) was changed and it did not fix the problem. The Svc Tech astutely observed, " because it only happens after the car has been parked for a while, it might have to do with a current drain. when the power is low it can do funny things to the computer"

Bigglen1

maybe the iPod is staying on and draining.

Arrie

Yes,

Low battery can mess up with the computers but if the battery is that low that the minimal current needing computer will get screwed up it will not be possible to crank the engine with that battery. Something else is wrong here.

mikeyle

i remember someone else on the forum having this done to the dryer and their car ended up smelling really musty and moldy and the service tech who disconnected it got fired or something. imho it wouldnt be there if it wasnt somewhat necessary

Live Oak

See my message, above. Fixing the dryer motor was originally done incompetently --- tech disconnected it (in software); never ran. Eventually we began getting "manure" smells from the vents when starting up. That's what the dryer fan is there for. So MB had to fix the thing twice (and the tech no longer works there we were told.)

And this is in the dry desert!

Bigglen1

Well the car's been at the dealer since Saturday. Still no word from them. I haven't called them yet.

Bigglen1

The dealer said they are replacing the rear SAM (systems acquisition modual) and one of the fuse boxes that they say has electronics built into it. I will get my car back today, eight days after I dropped it off. Originally they had replaced the front SAM. But it didnt cure the above intermittent issue.

ImInPA

It could be the alternator. If the alternator is not receiving the correct signals (the rear SAM controls this) the error messages can be triggered. I had this issue with my E350 Bluetec. The Alternator was being told by the SAM not to come on. The battery was low, but, the alternator should come on and supply the current to meet the demands. In mine, this was not happening. While I saw similar messages, once started, all of the function operated correctly.

Bigglen1

Picked it up. As I was originally told, they replaced the rear Sam and the fuse box only. I guess they deemed the alternator was fine. Only time will tell if the problem's rectified. The true test will be after it sits a few days and I start this Friday for the weekend's use!