jonta_dj

I have a year 2016 built in march. The collision prevention assist goes off randomly, showing the red triangle and makeing a loud beep. It seems like it's happening more often than before. Every time this happened the road has been free from other cars or people so it's strange that it is happening.

Anyone else experiencing this? I didn't fint it searching the forums.

Plutoe

Come on, that's a dealer warrantee issue----what's the real issue!!

alexasa

iTrader: (1)

Mine seems to always be working as intended.

The only time it goes off where it doesn't need to is when there is a car in a shoulder turning lane in the opposing direction, or a car turning off the main road.

hpilot

That happens to me occasionally, but it is very rare.

Abohunu

Happened to me too, but just a couple of times, I noticed the height of sidewalk was very tall and just passed very close from it.

SirC250

I also experience this issue many times and after I took the car into the dealer for another issue. I told them about this problem as well and they reset the onboard computer in my car.

Now two weeks after the reset I haven't had one falsely going off! (fingers crossed)

Aside note, I was talking to the MB technician about this issue and he told me he had a guy came in and complaining he almost got rear ended on the motorway by another car behind when the collision prevention assists went off in his CLA45 due to the auto brake engaging; bringing the car to a sudden stop!!

Geezus...now that's scary!

cptobvious64

Are you sure it's not the speed limit warning ? That used to confuse the hell out of me.

sadpanda

I've noticed that the material used to fill in cold weather-caused cracks in the road sometimes triggers the sensors when I'm going up/down inclines.

The material is mildly reflective, and I believe that causes the collision warning to go off. It's a small price to pay, considering that AEB technology is still in its infancy.

If your collision warning goes off on straight, flat roads, that's when I'd bring it in to the dealer.

ernieh

Mine did that; actually applying the brakes in narrow lanes. Cured by a software update.

Ernie

Sam Manuel

Mine keeps doing this ! I turn it off everyday which is crazy , it's back on when I drive the car next day<br/><br/>

GerritKw

I would bring it into the dealership immediately then.
I seen this message (or a similar one) twice in the 10 months I own it. Once when it was snowing (snow buildup) and once during heavy rain. Both fully acceptable in my opinion.
But your situation is not normal.

Sam Manuel

I want get it looked at when I go in for service B my car is also noisy as if front windows aren't all the way closed, just had them replace the headrest cause there was a shaking inside after the button broke

I feel like I go there too many times which is why I'm waiting on this one, I just switch it off every time I drive

What worries me is that it seems to kill traction control when it happens then it doesn't accelerate which pisses off people at stop signs ( Bay Area drivers aren't that patient)

jonta_dj

Thank you for your replies! It seems to be like I was expecting, other people are experiencing similar "problems".

I've read in another secion of the forums about Collision prevention assist going off in a different car model. Someone got their sensors realigned and maybe it is possible to make the sensors less sensitive.

I will bring this problem up to my dealer when I go there to get the acoustic glass installed.

My fear is what was mentioned by sir c250:
"...I was talking to the MB technician about this issue and he told me he had a guy came in and complaining he almost got rear ended on the motorway by another car behind when the collision prevention assists went off in his CLA45 due to the auto brake engaging; bringing the car to a sudden stop!"

Scary!

Jdem22

As others have said, take it in if it is happening too often. That said, when this first happened to me I pulled over and called up the manual for troubleshooting. I am paraphrasing, but basically "clean the sensors" and it started immediately working again.

GerritKw

Let's hope that MB service will check if the sensors are dirty before they start replacing or adjusting components then.

Jdem22

Yeah man, I would not have believed it if I did not see it/experience it. There may still be some underlying issue, but wiping everything down did the trick.

rongpanda

When I took delivery of my car, the dealer warned me that the collision detection would go off randomly, sometimes due to lamp posts or trees while turning, others due to elevation changes in the road. There have only been two times when the car actually applied the brakes, and that was in stop and go traffic, so they were justified.

Other than that, there are countless times when it would go off when nothing was around, but I soon realized that it was good that the car is over sensitive than under, especially in an instance when it ends up being necessary.

user 29474838

2015 C400, mine would do this 3 or 4 times during long road trips.
after about 2-3 minutes it would start working again "collision prevention assist is now availabel" would show in the display.

I took a look at the front radar unit in the grill and noticed the cable going to the connector was extremely tight. I mean really tight.
I managed to pull some slack to the connector and havent had an issue since.

CB949

Hi All,




I started a thread so we can get a head count on people with this issue, across different platforms. If your car's having this problem, please post here:




https://mbworld.org/forums/mercedes-...ml#post7833418