Hi everyone!
I just purchased a 2014 E350 coupe and had a question about the distance warning. It doesn't seem like its working?? I have a 2014 ML350 and 2010 E350 with distronic, and those distance warnings are very sensitive. I know this system isnt as advanced, but I've driven other vehicles with only the distance warning and they seem to go off fairly regularly (yes, I do drive a little aggressive). So is this feature indeed standard and operative? how close do I actually need to come to having a crash to get it to sound??

 

The collision prevention assist feature is indeed standard.. The range of the sensors seems to be about 60 to 80 feet by my estimation. With that kind of sensor range, it's obviously called collision prevention for a reason. The seat belt tightening up gets your attention almost as fast as the beeps. From what I have experienced, the system seems to work by the relative rate of speed you are closing to the vehicle or any other large object in your direct path to determine you are in danger of collision. Being stuck in bumper to bumper traffic doesn't seem to trigger the system as you're going slower than the minimum speed programmed into the system. I think you need to moving at least 20mph (may be wrong) for the system to function. I kind of like that it is not overly sensitive, as it becomes annoying real fast to be getting false alerts all the time.

 

Maybe this changed over the years, but my 2016 will beep and display a red warning light in the instrument cluster in slow traffic. For example, if I'm stopped at an intersection and the light turns green, and then I take my foot off the brake and start to accelerate, my car will warn me if it doesn't think the vehicle in front of me is accelerating fast enough in relation to my speed.

 

Thanks guys!! just confirmed mine is working.. kind of a quiet beep though.. it is much louder on my 2010 E350 and on my ML.

 

Is this system at all related to the distronic radar that sits behind the grill? I just put an aftermarket grill on my car (states its 100% distronic compatible and the plate looks like the oem one as far as thickness is concenred) and I feel like the collision prevention assist is going off too often. Granted this is happening when I am driving more "spirited". I am getting warning lights from switching out of a lane with traffic into a completely open lane. I've also gotten warnings when cars in the lane to my left and right have slowed down or just drive slower then me and I have passed them (again nothing is in front of me in this situation). Lastly I have gotten seatbelt tightenings during the same lane changes to an open lane on the freeway. In fact the only time i've not seen it beep is when i've driven close to someone directly in front of me and that was to test this system. Are these all normal things and do I just need to be on the autobahn if I want to drive this car to its full potential?

Btw: I did test the distronic plus cruise control and that works flawlessly, it brakes and accelerates normally in traffic or even high speed freeway driving.

 

Not sure if Distronic would use the collision assist sensor located in your front bumper as part of its overall array of sensors Distronic relies on. Distronic is a lot more sophisticated system than collision assist. From your description of how you're driving, it is possible to trick the collision assist system to think there is a problem if you quickly change lanes and the vehicle now in front is substantially closer than the vehicle you were just behind in the other lane. You can also trick the system by going around curves and if there is a sign post or other large metal item along the curve path, the system will momentarily beep as it scans the metal. Collision assist is strictly a forward looking, proximity warning system only. Doesn't take into account lane changing activity like when Distronic is active. So I have no idea why a vehicle either directly on your left or right hand side of your vehicle would trigger a beep from Collison Assist unless Distronic was also active at the time. Some part of those cars would have to be partially in your lane before they were next to you for the Collision Assist system to detect them as a potential risk. Overall, I would say your collision assist is working properly. Doing high speed zig zagging through traffic would likely cause the Collision Assist system to beep like crazy, if the system deemed you were too close to the car in front in the new lane compared to the old lane.

Finally to answer you question, yes you need to drive all these cars on the Autobahn as they were intended to be driven. There is no way you can truly enjoy the potential these vehicles have on our roads. Same holds true for any performance oriented vehicle from Europe. One caveat though, even on the Autobahn they frown on zig zag driving. You can go as fast as you want, just do so by their rules.

 

Thanks I assumed it may have to do with my driving style as I was changing lanes closely to the car ahead of me that I exited the lane from but to clarify the lane i switch to is completely vacant with nothing in it ahead of me. I wasn't really clear on how the distronic and the collision exist behave or if they both work together but wanted to make sure there wasn't something special in the stock mercedes distronic disc that the aftermarket one is not able to reproduce. The situation where the two cars were on both sides of me could possibly have been caused because i was far behind them so they were picked up as I approached (the radar for the distronic is supposed to cover a 90 degree sort of triangle angle). Does distronic pick up on break or red lights? Because I have noticed that it will beep during these situataions and have also seen it happen at a redlight before (no i wasn't running it but I did approach it somewhat fast). I called the dealership and they said that these systems can be thrown off by other radars/signals or even signals from an airport (the dealer near me is right next to an airport) and that they often have to reset the distronic systems. Not sure how much truth there is to this...

 

The system''s sensors are using radar-style technology as opposed to optically based. My guess is that the reason you are getting sporatic beeps when a car brakes in front of you taps his brakes lights, is that you were already following the car in front of you fairly close. The action when the driver tapped his brakes probably resulted in reducing the distance of the car in front of you just enough to trigger the system.

The thing you have to remember about these safety systems is yhat they were not designed for certain styles of what we may call "spirited" driving. When I was in Germany, most MB drivers told me they ended up shutting-off some safety festures they paid for, like Lane Assist, because they got tired of the steering wheel vibrating every time they opted to change lanes without signaling or had to make a quick, unexpected adjustment to avoid something in the road. Safety features like Collison Assist Prevention, Lane Assist and Distronic are designed to promote very safe driving styles and can be annoying as hell if your regular style of driving is on the more aggressive side as you described.

As your MB dealer has already told you, some of these system can be potentially triggered to generate false beeps or alerts due to interference from other electronic signals operating in the same frequency spectrum near by. The airport radar dish near the dealership must be a real headache for the MB dealersip. Just like radar detectors had to be re-designed a few years ago with a filter circuit to eliminate or at least suppress most false alerts when you're driving down the road for the same reason, at some point auto manufactures will have have to spring for a few more dollars more per vehicle to either add better filtering technology to eliminate this type of interference or add filtering technology they have decided to skip to date. The more the automotive industry rushes towards self driving vehicles, all of which will be loaded with massively more electronic sensors broadcasting on the very same frequencies these much more advanced systems will rely on for normal operation than today's cars,, the more auto makers will have to eliminate any potential for interference from external sources operating all around them.

 

 

Let us know what the dealer says. Most likely they will find nothing wrong as these systems are kind of designed to try and force the driver to "drive like granny". Which at times can be annoying to those of us that enjoy driving these vehicles to their potential occasionally. I pretty much know at this point how I could drive to create false alerts, so I know to avoid creating those conditions. These systems definitely will trigger lots of alerts, if you do any type of high speed, zig zagging or what the systems are programmed to conclude is either tailgating or accelerating too quickly towards the car in front of you relative to your traveling speed. Thus in some unsafe manner as the systems are programmed to check for.

Enforcing driver safety is the goal of these systems and their programming perameters from MB are tailored as such. Very predictable and orderly driving styles are what these safety systems seek to create through the various audio, tactile and visual feedback given to the driver. What you may consider to be "spirited" driving, the safety systems in your car are programmed to conclude is potentially dangerous and thus beeping like crazy at times.

 

Dnasty, a little off topic, but can you tell me where you got your grill? Mine got broken, and I've had little success finding a suitable aftermarket grill for my 2017 E400C4. I have Distronic and a front camera at the bottom of the grill. Any assistance would be appreciated.

 

Wouldn't be too off topic but you might be quite a risk taker if you are looking for a distronic replacement aftermarket grill as my car is still with mercedes and they are deliberating whether or not this (or some other component) is the cause of my radar system issues. If you are looking for a non distronic after market star they are all over ebay just type w207 grill. Mine I actually had got from a euro car aftermarket parts store in my area. This grill is not currently on ebay to my knowledge but if you are in the los angeles area pm me and I can give you their info.

 

Still in the shop? Did they pull any kind of error messages off your system when they checked it or are they just poking around to see if something is out of tolerance?

 

Was actually going to call them today, i've been busy but i'll keep you guys posted.

 

I received the car back and was told from the dealer that an iphone bluetooth/music adapter that I had plugged into the ipod output in the glovebox was causing these excessive false warnings. They said they reset the system and all the stored codes and it is functional now. I was skeptical because why would a bluetooth adapter for an iphone interfere with the collision prevention system but I've driven it on the freeway and so far have not had any unnecessary seatbelt tightenings occur (typically I would have had one by now).. even drove somewhat "spirited" to confirm and nothing so far. I have heard some beeps and they were as to be expected. Hopefully this resolved this issue although I still do not see the correlation as many people use these devices. It could be that they simply needed to reset the system.

 

So the problem was RF interference from the active Bluetooth adapter in your glove box with the Distronic / Collision Alert electronics in the head unit sitting right next to it. That certainly doesn't say much for the level of RF shielding MB used around their electronics in their head units to prevent cross-over signal interference. Wow. Hopefully that has been corrected in later model.years. Improper or inadequate RF shielding around circuits designed to process RF sensor data can indeed create all kinds of false events.

 

Possibly why they moved this cabling to the armrest cubby in later models. If this is the case though, I know there is an on going thread now regarding these aftermarket large screen headunits that do also incorporate bluetooth and sit right above the factory command I was contemplating doing this but have since decided to hold off. Wouldn't this also make their collision prevention system go wild?

 

Depends on the level of RF shielding those after market units have to prevent cross-over signal interference. If the stuff comes from China, then the quality can be all over the place. Standards are sometimes not exactly tightly enforced over there. Quality runs from everything being perfectly fine to over-priced junk that just looks good .All depends on the individual company over there. The problem you have is apparently your head unit isn't well shielded against stray RF emissions, so it was picking up frequency interference from the active Bluetooth adapter in the glove box next to it. MB probably fixed the issue in subsequent model years and they also relocated the Bluetooth adapter farther away from the head unit more for convenience at this point. Now if you go out and buy the after market display unit you mention and sit it on top of the head unit, you are potentially recreating your problem all over again. It depends are how well the after market unit is made and how sensitive your head unit is. At the end of the day, the head unit in your car is apparently not particularly shielded well against stray RF signals. So anything you place in close proximity to the head unit, like sitting something right on top of it, may be enough to interfere with your Distronic and Collision Alert systems. If I were you, I wouldn't bother with the after market display for that reason, as both a properly functioning Distronic and Collision Alert system is more important. Just my two cents.

 

Yea I will mention it in that thread. The unit is basically made by one company in china and rebadged by other companies it has to be affixed above the existing headunit as it replaces the stock screen. It requires running and splicing cables into the existing head unit so I would say it is more intrusive then a simple plug in adapter that goes into a glove box.

 

OK sounds good. I popped over to read that thread and read through all the posts and watched the videos to see what you are looking to do. The installation process seems as straight forward as most after market offerings are for MB. Anything involving accessing the wiring harness for the head unit entails pulling all that stuff out. If you ever saw how they assemble the dash at the factory, the first thing you would notice is everything is done from behind with them only flipping the dash around to finally add the Nav display and now on the newer models, the led panel that replaces the analog gauges. So as long as you take your time, have the right tools and are careful to not crimp any of the wiring when putting everything back together, it seems reasonable. Best of luck to you and hopefully your problem with Distronic and Collision Alert won't resurface with his new hardware in place.