parodielin

Today during a red light stop, the ECO mode activated and shut down the engine. The air conditioning is still on but the air wasn't "cold enough". It is code again after the engine turned on. It happened twice today. Is that normal? Is this a sign of the aux battery is dying?

s140s

Engine needs to run in order for the AC Compressor to operate and provide circulation in the AC system. After the engine is shut down the AC Coil will remain cold for 30seconds or so, it has no circulation due to engine being off, while warm air from the cabin is still forced through it.

parodielin

This is how I observed the system works too. The air wasn't as cold. I lower the temperature but not making difference. Once the engine is up, it is icy cold again.

Sounds like not a system issue. Just need to disable ECO if it's not cold enough.

PeterUbers

I shut eco off on hot days ...

pamiboy

I thought the Eco would shut off itself (become yellow) if the inside set temperature was too much different than the outside ambient air.

xthoms

Strange that the air condition wouldn't just shut off it itself.

nly04

I found out the ECO is annoying, too. Anyone know how to permanently shut it down instead of turn it of every time start the car?

nly04

The way ECO work will kill the starter in the long run because it make the starter work every time you stop at the stop light or a full stop at traffic.

cadetdrivr

I'm not sure about that. The starter motor on new(er) cars, and not just MB, with an ECO start/stop function is quite a bit more robust than the starter motors of yore.

That said, Mid City Engineering has an ECO Kill device for the W212.

http://www.midcityengineering.com/oe...-mercedes-benz

400ixl

Starter motor won't be any more likely to fail with ECO on or off, they have been tested and developed to do a huge number of starts over what any of us will put it through in its lifetime.

Diesel #2

This is normal, same thing happens on the 2016 models, i usually turn off ECO because it generally never comes on when i would like it too, like in a drive thru scenario. Plus, there is a slight delay when you take off from a red light while in ECO mode, which i do not enjoy at all. I will sacrifice the few drops of diesel i save and just turn it off.