swensodts

Seeking some answers wondering if anyone else has had this problem or if this something I can do to fix it?? Email to my service advisor:
I'm having an issue with my vehicle, wondering if there's a quick fix I can do - So, all the driver assists are shutting off every time I start the car in the cold. If it's warm, say above 30 degrees I have no issues car works fine.

The traction control, brake assist and lane keeping are all off when I start it in the cold only, below 25-30 degrees. When they're off the car will only run at half speed, is slow to accelerate and only goes 55 MPH in comfort mode. If I start the car in my garage where it is warmer I have no issue with any of the systems.

Do you know any way I can fix this issue without bringing it in?? Maybe ice is freezing somewhere?? I tried wiping off the sensors, I'll try that again but seems odd it's only when it's cold and the traction control is off as well. I cannot duplicate it unless the car is left outside in the cold.

Mr. J

Limp mode. Bring it in right away. You cannot fix this yourself. They should provide a loaner.

rustybear3

More importantly, if your are in limp mode, have your vehicle towed at this point. Limp mode gives you just enough time to drive home or to a service center. If at home now, call and have your vehicle towed in....driving to the center may cause more or permanent damage.

I'd call your service center to determine if your systems are indeed a limp mode problem. You can then proceed accordingly.

Tirgoman

And when he says 'towed' it should on a flatbed rig, not towed behind a wrecker. Dealer should arrange it under warranty. In the meantime, get your phone out and start videoing as you enter the car, start the car and video the dash so you can show the dealer the issue.

swensodts

So admittedly I've been pretty busy and have not gotten to the dealership to explore this cold start issue, however I did read the manual throughly as the car suggested....From everything I can tell and see it's actually a safety system function rather then a malfunction....In the manual it clearly says something about the correct operating or ambient temperature must be met in order for the systems to engage. What I'm finding is several conditions must be met for the systems to shut off upon start, A.) Temperature is below 20 degrees, that's about boarder line from what I can tell, in that I can shut the car off after the engine warms up, fire it back up and the driver assists will work, any temperature below that , where the car has been outside and they stay off. B.) The other condition seems to be ice, there must be some ice or snow on the car.... All of this actually allows the car to run much better in deeper snow and ice conditions then had they been on...The systems that shut off are ESC, which I often had to shut off anyway in the 2 previous Benz I've had when climbing hills in snow and ice, ESC prevented the power from being put down due to wheel slip. The adaptive steering, again you don't want the car steering for you or correcting itself in the snow or ice and adaptive braking, same reason....The other thing it does is cut the throttle response to prevent laying down too much power and losing control, this can be overrided with manual paddling shifting if you do need more power....All in all I'm confident it's a built in system feature rather then a defect....Drove 250 miles in 3-4" snow in 9 degrees with the systems off over the weekend and she handled like a champ.... I'm going to call the dealer to confirm and any info to the contrary where the car has been left outside in snow/ice under 15 degrees Fahrenheit is most appreciated