wrong speed limit detected
Thread Starter
Newbie
Joined: Jun 2011
Posts: 14
Likes: 3
Current: GLS 350d - X167, E 250 CDI 4Matic W212, Past: E 280 CDI - MB211K
wrong speed limit detected
Hello,
I usually drive with the cruise control on when in the highway. The system is nice enough to detect speed limits and adjust the car's speed.
There is this highway close to my home (tangential di Milano) that has speed limits specific for trucks. This particular sign is the same as a speed limit with the addition of a regulatory sign that specifies that the speed limit applies only to trucks.
In conclusion the speed limit signs alternate between 90km/h for cars and 70 km/h for trucks.
The GLS ignores the regulatory sign and suddenly slows down, then sees the sign for cars (90km/h) and accelerates, then again a speed limit for trucks comes and speed is down to 70km/h. This is annoying since cars do not expect my car to slow down all of a sudden ...
I tried to tell an Italian MB retail shop about this issue and they told me that the GLS computer did not record any anomaly so the car was fine ... no comment on this ...
Any one has a suggestion on how to report this to MB so that they can think about a fix ?
I usually drive with the cruise control on when in the highway. The system is nice enough to detect speed limits and adjust the car's speed.
There is this highway close to my home (tangential di Milano) that has speed limits specific for trucks. This particular sign is the same as a speed limit with the addition of a regulatory sign that specifies that the speed limit applies only to trucks.
In conclusion the speed limit signs alternate between 90km/h for cars and 70 km/h for trucks.
The GLS ignores the regulatory sign and suddenly slows down, then sees the sign for cars (90km/h) and accelerates, then again a speed limit for trucks comes and speed is down to 70km/h. This is annoying since cars do not expect my car to slow down all of a sudden ...
I tried to tell an Italian MB retail shop about this issue and they told me that the GLS computer did not record any anomaly so the car was fine ... no comment on this ...
Any one has a suggestion on how to report this to MB so that they can think about a fix ?
Junior Member
Joined: Mar 2021
Posts: 27
Likes: 17
GLS 580
Strange, but I experienced that problem for the first time yesterday. Usually, the speed limit detection is right on, even recognizing reduced speeds in work zones. Yesterday, on a 200 mile trip on the interstate, the 580 reduced its speed from 75 to 55 three times and once cut the speed to 40. Each time that happened, I had just passed a speed limit sign that announced that the maximum speed is 70 and the minimum speed is 40. The speed limit signs in my state look just like the graphic speed limit sign in the HUD, so strange signage is not the problem. In addition, a warning on the instrument screen has been coming on repeatedly in the last few weeks that says "camera view unavailable." And there are no bugs on the cameras.
Junior Member
Joined: Mar 2021
Posts: 27
Likes: 17
GLS 580
Nope. There wasn't a cloud in the sky on a 400 mile (200 each way) trip yesterday. It has been going on for several weeks now, even on short trips. Can you imagine what would happen if Boeing built its 737 series airplanes with this many software bugs?
Newbie
Joined: May 2021
Posts: 10
Likes: 5
From: Sweden
GLS 580
I have had similar problems, including mine picking up the lower speed limit signs on off-ramps (when I’m not getting off). There is one road I drive regularly that is 90 or 100 most of the time, and in two different spots it randomly starts slowing down (I haven’t noticed what it is slowing to - too dangerous with cars behind me to let it keep slowing down). Very annoying, but I attribute it to the camera mis-seeing something,
Member
Joined: Apr 2022
Posts: 78
Likes: 33
From: Medina Ohio
2022 GLE
Hello,
I usually drive with the cruise control on when in the highway. The system is nice enough to detect speed limits and adjust the car's speed.
There is this highway close to my home (tangential di Milano) that has speed limits specific for trucks. This particular sign is the same as a speed limit with the addition of a regulatory sign that specifies that the speed limit applies only to trucks.
In conclusion the speed limit signs alternate between 90km/h for cars and 70 km/h for trucks.
The GLS ignores the regulatory sign and suddenly slows down, then sees the sign for cars (90km/h) and accelerates, then again a speed limit for trucks comes and speed is down to 70km/h. This is annoying since cars do not expect my car to slow down all of a sudden ...
I tried to tell an Italian MB retail shop about this issue and they told me that the GLS computer did not record any anomaly so the car was fine ... no comment on this ...
Any one has a suggestion on how to report this to MB so that they can think about a fix ?
I usually drive with the cruise control on when in the highway. The system is nice enough to detect speed limits and adjust the car's speed.
There is this highway close to my home (tangential di Milano) that has speed limits specific for trucks. This particular sign is the same as a speed limit with the addition of a regulatory sign that specifies that the speed limit applies only to trucks.
In conclusion the speed limit signs alternate between 90km/h for cars and 70 km/h for trucks.
The GLS ignores the regulatory sign and suddenly slows down, then sees the sign for cars (90km/h) and accelerates, then again a speed limit for trucks comes and speed is down to 70km/h. This is annoying since cars do not expect my car to slow down all of a sudden ...
I tried to tell an Italian MB retail shop about this issue and they told me that the GLS computer did not record any anomaly so the car was fine ... no comment on this ...
Any one has a suggestion on how to report this to MB so that they can think about a fix ?
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Junior Member
Joined: Mar 2021
Posts: 30
Likes: 5
GLS580
MB's software likely recognizes both speed limits and can probably distinguish which sign is applicable to you, but there are a number of more nuanced cases where only drivers can make the call. For example, I've seen plenty of signs that say something along the lines of X MPH WHEN WORKERS PRESENT Y MPH ALL OTHER TIMES. Or two speed limit signs stacked on top of each other -- the normal speed limit followed by the school zone limit. The technology just isn't mature enough to distinguish between "workers" and people standing on the side of the road, or determining if school is in or out of session (is today a half-day? does Thanksgiving break start on Mon or Tue?). So instead of guessing, the car plays it safe and goes with the lower limit.
This isn't just a MB thing, and it's not just road signs. When driving you're making one judgement call after another, both consciously and subconsciously. Manufacturers are spending billions trying to figure out how to solve for that. The technology is evolving rapidly but it's not even close to being there.
Last edited by neetorama; Nov 14, 2022 at 09:31 AM.
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Super Member
Joined: Mar 2022
Posts: 556
Likes: 197
From: NJ
2022 GLE 450
Totally agree with @neetorama . One cannot rely 100% on tech. Otherwise would could all just read a book while driving. I believe this happens to most of us. I have become accustomed to it, and simply just hit the gas and reset cruise control speed. I have also experienced the opposite - while driving over a bridge with a stated 55MPH limit, my GLE suddenly accelerated to 80MPH. I looked at the HUD, and it was displaying 80MPH. Very odd. I never reported it to MB cause they probably wouldn't be able to duplicate it.
