cheong651

Hi

My new FL W204 MY 2012 has ECO function, but I found some problem in using it.
Per my understanding, the ECO button will be "green" each time I start the engine, in case the driver does not want ECO, just press once to switch it off.

Remark : before two weeks i discover eco function did not work, than i change the aux battery (bosch BLA-12)

However, I switch engine on as normal, the ECO does not automatically on AND even no response with my manually pressing the ECO button. So...this journey was driven with no ECO, no matter I try to press the ECO on in between, still no response.

If I switch off the engine, take out the key and then switch the engine on again, the ECO button "on" automatically that I can press it to off or on manually.

I know there are so many conditions for ECO to on, but it seems strange that if I switch off the engine and restart it immediately, the ECO can auto-on.

michail71

So it does not come on at all? Or should I say the engine does not turn off at a stop?

I'm sure there are a lot of people that would like to have that happen to their car. I actually like it as it can make traffic stops at long lights a little more peaceful. But my car does not have the function.

Antique-Ace

+1
I REALLY wish my ECO button would become permanently inoperative in the "off" mode to save me the trouble of having to turn it off myself every time I start my car!

cheong651

I agree

michail71

Also, if anyone knows how to break E mode please let me know.

xEryx

I was looking around with STAR and I found a setting that lets the car start on E in 1st gear which is a big part of what S does although not everything.

capt_paul

So....I assume that your car did not come with an owner manual? It explains the system and all the conditions that must be met for ECO function to work

cheong651

First..........tks for your reply
I saw the manual, the manual say , if cannot met the condition , the eco symbol also can showing in mutil function srceen until i turn it off........but the problem is, when turn on the engine , the yellow eco symbol showed in multi function screen, but after running about 2 and 3 min the yellow eco symbol was disappeared and cannot turn on again. Than i running about half hour in highway the eco symbol also cannot showing in multi function screen.

1. w204 had eco function model cannot use oem battery and must be use original auxiliary battery?

capt_paul

If the ECO mode is on (by default when you start the car), the ECO should initially be yellow Neil all conditions listed in the manual are met, then it will turn green, which indicates that the system is in the ready mode. Now, if the indication just disappears altogether while driving, you have some malfunction within the system

tripper80

hi, have you fixed it? the ECO died out after i changed the battery(kirkland from COSTCO). Before the change, the start/stop function occasionally works seemly when the battery is changed full.

mine is 2013 c300 3.5L 4 matic sport with start/stop. I cannot find the aux battery under hood.

pcy

Look in the trunk (next to spare tire) for AUX battery.