Intermittent Red Triangle warning light

[TonyWilliams]

Every once in a while, without warning, a red triangle pops up with a warning sound and just as quickly goes away. Seems to happen daily.

 

[pathiel]

I've had same experiences. I suspect that it's related to forward looking sensors detecting rapid closing distance between you and an object (e.g., vehicle) in front of you, but in an adjacent lane (e.g., another vehicle in a right turn lane that you are about to pass on the left).

 

[baysal]

I agree.
Your car has a Collision Warning system that uses a Radar sensor up front. If it thinks you're about to collide, it warns you with 2 beeps and the red triangle (upper left).
I have had circumstances where it beeps for no obvious reason, but generally the beeping is justified. Maybe I am a little aggressive in my driving?
I think you can shut the warning off in the cluster, but I haven't tried it.

 

[wiredjawz]

I've noticed the same thing. Anybody have any other insight on this issue?

 

[pathiel]

I've experienced more and more of these events, many of them where there was no vehicle, or even object, anywhere within a range that could reasonably be considered worthy of a warning. (Road surface excepted, of course.)

The most frequent of them seem to occur in roughly the same general area along my routine commute path, and either in the pre-dawn/very early morning, or well after sunset. (I frequently do the same commute during daylight hours, and it seems as if there are less events then.)

I'm beginning to suspect an atmospheric condition (think temperature gradient or fog) may be causing a false trigger of the internal algorithm. If so, it seems likely that either:

1) all Benz autos (with this feature) would suffer the same/similar problem
2) ICE vehicle engine heat might prevent the same false trigger
3) it was necessary to modify the algorithm for the EV and they didn't do enough real world testing (e.g., under similar climate conditions) to catch the problem before launch

If a techspert was to tell me it was related to passenger weight/balance, i wouldn't be shocked because it also seems to occur more when i have a passenger in the front seat.

 

[JupiterRed]

In addition to the B-Class, I own an CLA as well. Over on the CLA forum, there have been a number of cases where people get the warning all too often. It took Mercedes a while but some owners found a loose sensor. You cannot see the Collision sensor as they are under the bumper cover. They are not in the "star" nor are they the parking sensors that you can see on the bumper.

Once the loose sensor was fixed, the problems went away.

If you want to research it yourself the forum is MERCEDESCLA.ORG. I have the same handle on that forum as here. I believe Tuxedo Cat was the person on the forum who suffered from the problem.

That said, you will get an occasional false alarm.

 

[mddg]

I've had that warning light with beeping twice, but it's gone almost as soon as I notice it. Based on the various webpages, I think it's the Distance Warning system that's configurable (on/off) from the dashboard menu.

I have gotten some other odd warnings too and wanted to know if others have seen these. "Charging cable connected" on key entry even when it hasn't been connected for hours, Malfunction - Visit Workshop" or something like that, also on start up. Both these odd messages disappear after starting.

Edit: Got that warning again today after charging at public charger - "Malfunction - Visit Workshop", but no obvious problems starting.

 

[pathiel]

Thanks JupiterRed. I'll give that a look-see.

 

[Anonymous]

It's the Distance Warning Sensor. A bit too sensative for my taste or as suggested it could be a problem with the sensor itself. It CAN be turned off in the Settings menu on the steering wheel cluster. I'll have them check sensor issues next time I bring it into service. For now the problem/annoyance is gone.

 

[ophthodawg]

i've experienced the same "false alarm" a few times with no vehicles around. A minor annoyance so far

I would not turn the system off though. it is designed to save you from a front crash. I'm happy to put up with a few false alarms for the protection the system is designed to provide.

I am curious though... as I understand the system if you engage the brake during the warning I think the car is designed to apply the necessary brake force to help avoid the crash, i suppose you could then get rear ended if you inadvertently and suddenly came to a stop... hmm