When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
My EQE developed this odd error after the s/w update to 505.
Between my home, and a stretch of 101 in Northern California about six miles away, the speed limit display flashes.
When I leave my home in the morning I drive about 1/4 mile on a "driveway" that serves a few homes, to a small road that leads to a larger road. Leaving the house there is no display, when I reach the first small road, it flashes with no speed, when I reach the larger country road, it flashes with the posted speed limit. It continues through town, and onto South 101 for about 5 miles, flashing the 65mph speed limit on the freeway, then stops flashing at the same location.
Returning home from the south, north on 101, it may or may not begin flashing at about the same location, and continue until I turn off the second small road that leads to what is effectively a long driveway for three homes.
You can see the flashing in the attached video. I had to dramatically downsample and edit the video to make it small enough to upload. You can see the flashing sign. Sometimes it will alternate between the US style sign, and a round sign within a red circle, the European style speed limit sign.
The dealer is of course mystified. They fooled with the car for two days, but weren't able to do anything useful. It only does this on a specific stretch of road and freeway. And usually only on the first drive of the day when departing. My guess is that there is some data missing in the nav db and a software bug that doesn't know what to do with the missing data, but that doesn't quite explain the fact that it doesn't always do exhibit the bug. It always does this on the first trip of the day from home, but only sometimes when returning home.
While it is flashing the auto lane change function is disabled and flashing on the main display (the invoked by pressing the car icon), and the lane change with steering assist invoked with the turn indicator stalk does not work.
I know that it normally flashes three times when the posted speed limit changes so this may be a bug in that s/w.
As explained in the owner's manual. The speed limit sign with just dots in it is displayed when the system cannot determine the maximum permissible speed due to lack of signage for example. It is supposed to fall back to the default national speed limit of the road you are currently driving on, or the speed limit that's stored in the map database for the current road if it can't detect a speed limit sign for a certain distance. Where exactly on 101 is this happening? I know parts around Petaluma are under construction. Might be that the speed limit data is missing from your map database, so if it doesn't see a speed limit sign for a while, it won't find a speed limit in the database, either, so it doesn't know what the speed limit is until it sees a sign again. When this happens, do you remember how far back the last speed limit sign was and does it show the speed limit again as soon as you pass another sign? Basically the question is does it detect the speed limit sign when there is one? If data is missing from the navigation database or is currently incompatible with the latest firmware then hopefully this will be corrected with the next map update. It is possible that they changed the map database schema and you currently have a mismatch between an old schema and newer software.
I Get 85 indicated in a 1/2 mile stretch in town where it is 40 and Car takes off if I'm on cruise conttol !
DISTRONIC automatically adopting the current speed limit can be turned off in the settings. I've turned this off a long time ago as I don't find it very useful here in the USA. I did use it during my European Delivery due to the ever changing speed limits over there and the strict enforcement with speed cameras around almost every corner. Helped me avoid getting unwanted souvenirs in the form of a speeding ticket, but here in the USA speed limits are more of a guidance than a hard fact and no speed cameras, at least not yet.
Last edited by superswiss; Mar 14, 2025 at 01:33 PM.
I also turned off Adaptive Speed Control when the car did a maximum braking from 45 mph to 15 mph when I drove past a closed school. The car isn't smart enough to read the posted hours when the limit is in effect. In Florida there are lots of signs with effective hours or days or "when children are present".
As explained in the owner's manual. The speed limit sign with just dots in it is displayed when the system cannot determine the maximum permissible speed due to lack of signage for example. It is supposed to fall back to the default national speed limit of the road you are currently driving on, or the speed limit that's stored in the map database for the current road if it can't detect a speed limit sign for a certain distance. Where exactly on 101 is this happening? I know parts around Petaluma are under construction. Might be that the speed limit data is missing from your map database, so if it doesn't see a speed limit sign for a while, it won't find a speed limit in the database, either, so it doesn't know what the speed limit is until it sees a sign again. When this happens, do you remember how far back the last speed limit sign was and does it show the speed limit again as soon as you pass another sign? Basically the question is does it detect the speed limit sign when there is one? If data is missing from the navigation database or is currently incompatible with the latest firmware then hopefully this will be corrected with the next map update. It is possible that they changed the map database schema and you currently have a mismatch between an old schema and newer software.
Yup, that's the display, thought it sometimes shows the European version.
The problem is that it's not consistent, and will flash when there is signage. Southbound the problem is from my house outside Healdsburg, until I reach Windsor on S 101. Northbound it starts at Windsor, sometimes, and flashes until I reach the one lane road up to my house. I think this is a bug between s/w and nav db.
I've owned five Mercedes and it's just tragic to watch a great engineering company fail so badly. UI/UX, software quality, software in general are just awful and it may reduce the company to a shadow of its former self. It kind of reminds me of Kodak. The king of photography, until it was no longer about chemistry.
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren
Slideshow: A one-of-one U.S.-spec Mercedes-Benz SLR McLaren Roadster became even rarer after a factory-backed transformation at McLaren's headquarters.
