W205C43PFL

Shouldn't had doubt a veteran
Anyways, thanks again for your help.

ddeliber

Just yesterday I noticed that this is not just a HUD symbol. It shows up in the standard assistance monitor (similar to the same in the HUD) in the center display between the gauges. I never use that monitor but I thought about this thread and wanted to give it a shot.

To me It looks like an "undocumented feature" in the drivers assistance package. I noticed the car slowing down when coasting while approaching a car in traffic and it feels like the car is lightly applying the brakes to attempt to pace the car up front and this symbol demonstrates that the car is at least recognizing something. Personally, I think it is pretty useful and cool. I could also see how some owners might not like their car braking automatically at all during normal driving conditions (non-emergency situations). Maybe this is why it isn't "well documented/advertised" as Mercedes didn't want to have to deal with that "justification". I asked my son to look to see if the brake lights came on when it happened and he couldn't really see but he thought that he saw an increased glow back there from his spot in the passenger seat. He's 15 and on his phone so he wasn't really interested, maybe someone else could check that.

John Tzezanas

I had the time yesterday and I made a lot of tests.
I saw that it lights in 2 faces, as another member here stated, when you approach fast to the front car it lights on but sometimes without the dots just to make you cautious.
When also the green dots appear (sometimes simultaneously, sometimes not) it always uses recuperation and the breaking which I assume is not really breaking by brakes. You can check in the night and see that the stop lights do not come on.

Mikey53

I believe the “recuperation” in relation to this symbol is only in your imagination and more likely you easing your foot off the gas. Brakes aren’t applied unless the red triangle appears. That is my experience.

I have the assistance monitor displayed almost 100% of the time so I see the symbol lots during freeway driving.

John Tzezanas

Your don't understand. No one is saying, brakes are applied.. you just feel the car is slowing in a faster pace (maybe just because the altenator of EQ boost is engaging). All this for the 48v E450. I am also sure by now that when the green dots are on, then it always recuperates. If not also the green dots on, then it just warns your as you have said. If white car on and green dots on, the car warns and recuperates also. You can watch the EQ boost symbol also at the screen to go full green. I just tried to make it more clear now to be easily understood.

Brakes are only applied only when the big red symbol and not the small one comes on.

If needed, I will make another more comprehensive video to make it clearer.

ddeliber

My car absolutely decelerates noticeably when the symbol comes up.

Anyone can it for themselves. Cruise at 55ish on a multi-lane road, lift off the gas as I approach some traffic, coast smoothly then once I reach just past the 100ft bar on the display for a slower moving car in front of me after 15 or so seconds of coasting freely and the symbol shows up and the car starts to actively slow down. I do not know for sure that the brakes are applied as I didn't design it, but I watched the tach/gear display and it sure does not downshift. Not sure what else other than some light brake force would do this.

Recuperation is a side affect of whatever it is. I see the same regen bar go up whenever I touch the brakes and sometimes when I don't (comfort mode coasting down a hill - consumption goes to 999mpg on the consumption gauge).

John Tzezanas

Exactly this!
I also think that maybe the huge 48 alternator is engaging and causing this slow down so the recuperation is not a side effect but what causes it to slow down, just an idea!
I noticed also that sometimes only the car without the green dots comes on and in this case the car does not actively slow down but only when the green dots are on and of course the green EQ boost bar full green also.