Drivers Assistance Plus Review




- You can adjust the speed at pretty much anything over the posted speed limit. It does not seem to use posted limits for anything other than to display them.
- You “Suspend” the function by putting your foot on the throttle and adding pressure. It returns active as soon as you release the accelerator.
- Like any Cruise it turns off when touching the brake. Resume button reactivates it.
- The Lane Keep is no longer active if you Suspend it. In a way I like that because it solves the unpleasant jerk and braking if you cross a solid line. I didn’t realize how often that can happen dodging a pot hole or moving over when crowded by an adjacent vehicle. There is almost zero tolerance for the jerk and quick brake. My System is set at the factory “medium intervention”.
- The lane change function is more useful than I expected but requires you to turn on the turn signal. If it’s clear it will change lanes but not predictably. At times it’s smooth and gradual but sometimes turns quickly and the jerks as it reaches the outer lane marker. I tested it twice with a vehicle in the lane and it did not change lanes-Aborted the Command.
- Sometimes there are system errors or maybe the car thinks it sees a hazard when there is none. Several times things like an underpass, truck ahead or turning a corner activated the braking function.
- On some corners it will slow down 4-6 mph but doesn’t appear to follow any traffic sign. In some cases it slowed with no sign present but maybe heavy traffic triggered something. It’s not reliable on curves and occasionally crosses lanes on straight roads. There were probably 4 times the driver alert flashed requiring me to take corrective action. Didn’t appear to be poor lane markings or sun.
- At times the Distronic function works very well but in some cases it’s unsatisfactory. At Freeway speeds it may wait too long to slow down and then brakes hard. The same thing happens when a car cuts into your lane. Worse is the way it resumes speed in an abrupt manner. When the car has slowed down 10-20 mph it has a tendency to go half throttle to get back to speed. In these situations the hard braking and fast acceleration create another Jerky condition and has to hurt fuel economy. I soon got back in the habit of tapping the brake to start slowing sooner and gradually accelerated back to speed before hitting resume.
- I was under the impression that attention was monitored by sensors in the steering wheel but that’s not how it works. It senses inputs on the steering wheel so that on a straight road you will get a warning. Our Audi works the same and has a 10 second limit but Mercedes is more tolerable at about twice that. I drove for about 15 miles with my hands off the wheel but periodically pressed an inside spoke section of the wheel.
- At 3 hrs 45 minutes of continuous driving I started getting a notice to take a break. It appeared 3 more times in 15 minute intervals. Germans have a sense of humor….a mug of beer appears in the notice.
The System has a lot of potential but really needs some fine tuning. The hardware is there so maybe future updates will help. I will use it some on long trips but it might be dangerous for some people. The unexpected jerky corrections are one thing that might cause alarm. Crossing into the wrong lane might cause an accident! Several competitors have a better system. Hope the over the Air updates bring help soon.
Last edited by Ron.s; May 19, 2019 at 08:36 PM.
Maybe sensros are not installed properly and pointed up a bit?
Does it show up on speedometer as car in front going slower?
OR is this maybe from all the auto braking systems the car has and not the distronic?
Tech in your car is in all the other models with distronic and mine does not slow for overpasses.
I used if for 900 mile trip once and never had issues other then the person cutting in front very close - yes it applies the brakes then.
Yes it is slow to accelerate then I would but about as my wife would...
Wish they would allow a few more variable for drivers to set beside speed and distance...
Like accel rate and normal brake rate for car in front.








Maybe sensros are not installed properly and pointed up a bit?
Does it show up on speedometer as car in front going slower?
OR is this maybe from all the auto braking systems the car has and not the distronic?
Tech in your car is in all the other models with distronic and mine does not slow for overpasses.
I used if for 900 mile trip once and never had issues other then the person cutting in front very close - yes it applies the brakes then.
Yes it is slow to accelerate then I would but about as my wife would...
Wish they would allow a few more variable for drivers to set beside speed and distance...
Like accel rate and normal brake rate for car in front.
In my case the System accelerates too fast after the Distronic braking is applied. For example-traveling at 80 a semi pulls over to pass another truck on a 4 lane hwy (2 each direction). My car slows to 55 mph and works as it should until the lane clears and then it accelerates rapidly sometimes shifting down from 9th to 5th or 6th gear, engine roar and all! Just seemed unusual fo me and definitely not smooth.
The cost of the Driver Assistance Plus was $2350 but required the Multi Contour Seats $1100 and they required more options. This is a complex System that needs to work better to be useful. If my wife is at all typical many people will refuse to use it in its present form.
Edit-where I said Distronic works as it should in the truck scenario above I take that back. That’s the exact situation when my vehicle approaches at 80 mph and then brakes hard since the truck is going a lot slower. It would be nice if it slowed sooner eliminating the need to brake agressively.
Last edited by Ron.s; May 20, 2019 at 06:04 PM.
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Anyone see any reasons why I should just keep it on the build?
Been readily a lot of not so positive reviews on this package.
What is DA2-292 Side Airbags?




https://www.mercedes-benz.com/en/mer...benz-pre-safe/
I love it.
There are some FANBOY threads on here if you look.
My wife complains too so I use it much less now than when I first got the car. I still think this feature as a safety/backup driver, in case I feel tired on long ride.




On another related note-has anyone permanently turned off the Active Lane? I have an inquiry to my dealer to see if they will do it. It’s more of an annoyance than the Distronic Plus. Mine resets to on after turning the car off.




I now feel like I would definitely buy the Drivers Assistance Plus again but only because I make numerous long trips. It would also be useful for big City traffic congestion. I still feel the System is not reliable but I can get by adapting to it and understanding the weaknesses. It’s spooky at first when it jerks, lurches, crosses out of the lane or brakes hard for no apparent reason. On straight roads under most conditions it does its job well. I feel that I was able to relax more and it offers an element of safety. Rather than staring at the road all day I was able to look around more keeping the road in my peripheral vision. This seems to help with eye strain.
I recall reading that it has cameras and radar. It might be that assimilating/calculating radar data and camera data isn’t perfected yet or isn’t fast enough. The system seems to work better at lower speeds so those driving 60-70 may experience less of the issues or it’s remotely possible it’s just glitches with my system.
I won’t rehash the things I mentioned in the first post but now think that I understand them more.
CURVES-The system has consistent issues with curves It will not hold the lane at 80 mph on moderate curves. At 50 it had no problem with two sharp ones in a detour. It could be that the System can’t process data fast enough at speed. On curves a vehicle in an adjacent lane might trigger braking or deceleration for a short time but not always. The System frequently slowed unexpectedly on an inside curve with no vehicle In view. I noticed it occurred when there was irregular terrain like small hills close to the road. Tall walls along the side were never a problem but short concrete barriers were. Most of the issues were on curves and the result is the system doesn’t react quickly to notice the driver to take over. It might be 5’ into another lane before the warning.
Straight Roads-The System seems very reliable on straight roads or gentle curves. The only issue I had today was in a section where the Freeway had numerous cracks that had been filled. The criss cross black pattern apparently caused the issue and the warning to take control came on.
Rain-Heavy rain didn’t seem to cause any issues with Distronic and even Lane keep seemed OK. I assume that Radar is involved with Distronic since visibility was so poor at times.
Misc-Early in the trip an overpass caused hard braking. There were no support pillars anywhere near the roadway and I couldn’t identify any reason it happened.
Hopefully there will be some upgrades to the software making it more reliable!
Literally EVERY AAC has problems with curves. Never, ever rely on any system around serious curves. Slight bends in the road is usually max that most systems can handle.
"Misc-Early in the trip an overpass caused hard braking. There were no support pillars anywhere near the roadway and I couldn’t identify any reason it happened."
Perhaps the system saw some shadows and/or breakage in the yellow/white lines.
Last edited by superset; May 21, 2019 at 09:28 PM.




Literally EVERY AAC has problems with curves. Never, ever rely on any system around serious curves. Slight bends in the road is usually max that most systems can handle.
"Misc-Early in the trip an overpass caused hard braking. There were no support pillars anywhere near the roadway and I couldn’t identify any reason it happened."
Perhaps the system saw some shadows and/or breakage in the yellow/white lines.
The underpass had no issue with lane markings, the loss of them don’t trigger aggressive braking anyway. That braking only happens (in my experience) when Distronic detects a Vehicle or object it thinks is in the lane of travel.
Personally I will have a hard time ever trusting any Driver Assistance Program.








Our 2020 450 had problems with cameras and sensors - so much that it was bought back. Miss the E-ABC.
With some trepidation, we ordered a loaded '21 53, and it's been trouble free....
Except after a windshield replacement, where the camera couldn't be calibrated.
Culprit discovered!
The Dealer found two TSB's regarding film/haze on the camera lens and glass, applied the alcohol and heat procedures and no further problems.
That was late 2021.
Now the cameras are supplied with protection (I think) from that hazing, and we haven't seen recent reports from newer cars.
I have recently been doing a lot of cross country driving, and I've been using Active Steering Assist (not Active Lane Keeping Assist - too aggressive for my taste, uses braking) on long stints, freeways and secondary roads, and it's impressive and reliable.
It does hand off control back to the driver when lane markings are hardly visible.
I actually trust it to navigate sharper corners and narrow bridges next to semis, but of course I must touch the wheel every 30 seconds, per Fed law.
Watching the MB compared to Tesla's VERY expensive subscription solution (YouTube), it looks like the Tesla implementation is inferior. It can't even change lanes on it's own.😧
I never thought that I'd ever rely on, much less trust, a Nanny like these, but I find that I arrive more refreshed, partly because I take the time to look around more.
You know - traffic, mirrors, gauges, traffic, mirrors, gauges etc. Now I add "distance view" to the mix. It's an important part of 10 hour driving that I often forget.
I also don't like "route based speed adaptation" because I corner faster than the warning signs, but it also works if you want it.
Distronic seems much smarter in my '21 than my '20.
Add Distracted Driving as a peril these days, and I'll take some additional Nannies.
Probably a resale problem on resale without it.
Of course, you can disable or ignore the Nannies if you want to play.
Last edited by mikapen; Oct 15, 2023 at 02:57 PM.




Mercedes seems to be the leader with SD Tech but that’s on a different system.




Mercedes seems to be the leader with SD Tech but that’s on a different system.
I did have two "camera view restricted" that disabled the system, but it was bugs. First instance - three long bursts of wiper fluid. Second - Needed a gas station scrubber to clear.
Regarding Tesla's $199/month subscription, it's not a Full Self Driving mode. It's more like Mercedes Driver Assistance Package.
Quote from Tesla: "The currently enabled features require a fully attentive driver, who has their hands on the wheel and is prepared to take over at any moment."
https://www.tesla.com/support/full-s...y-subscription
Mercedes is the only manufacturer with FSD passenger cars in the US right now, only under limited conditions and locales.
https://www.teslarati.com/mercedez-b...al-california/
Last edited by mikapen; Oct 15, 2023 at 07:25 PM.



