Model S

Posted speed limits signs not recognized.

edited November -1 in Model S
Was wondering why some speed limits signs are not recognized on my Tesla..

Don’t need a ticket.


  • edited March 2019
    HW 2 and HW 2.5 do not recognize ANY speed limit signs. Only HW 1 can do that as of now. There has been a promised update for it, but it has not shipped. At this point the speed limit comes from a poorly maintained database. For example I live on a standard residential tract house street. Half way down my street, the speed limit in the car shows 45 MPH. But the speed limit is 25. This is common. For my normal driving the database is about 80% accurate. So if you want to avoid a ticket, ignore the screen and watch the signs. It can be a handy guide in an area you are unfamiliar with - but you cannot rely on it.
  • edited November -1
    Tesla NAV currently uses GPS for speed limits--does not read signs.
  • edited November -1
    Tesla NAV can read speed limit signs but only on AP1 cars. MY P85D reads the 15-mph sign that I personally installed on our driveway - proof that it does so, because it is a 1-mile-long private road and would not be listed in a GPS database, and the speed limit isn't technically legal - but I did have it made by a professional road sign company, so the car sees it as real. Our friend's newer AP2.5 car cannot read that sign.
  • edited March 2019

    So how will FSD maintain proper speed limit? GPS only?
  • edited March 2019
    "So how will FSD maintain proper speed limit?"

    That's least of potential FSD's issues.
  • edited March 2019
    Jerry, JPP, PD, Hammer +1

    Silver2k +1 ( recognizing good points )
  • bpbp
    edited March 2019
    AP1 was using Mobileye's technology to read speed limit signs.

    When Tesla dropped Mobileye for AP2 and shifted to their own "Tesla Vision" software, they lost the speed limit sign feature. The software is likely detecting the presence of traffic signs, but not yet reading them.

    The onboard speed limit database currently being used for AP2+ is pretty bad, with many instances of missing or incorrect (too high or too low) speed limits. And when the AP2+ software uses that data, it will sometimes drive too fast or incorrectly slow down when it has the wrong speed.

    Traffic sign detection is supposed to be coming soon - not only the speed limit signs, but the other traffic signs and signals needed to implement NOAP on surface streets.

    Patience... Though when they do roll out that feature - we won't trust it and will continue to closely monitor NOAP, just like we would with a student driver...
  • edited March 2019
    Speed limit databases apparently don't get updated very often. When the road near my house was widened they reduced the speed limit from 45 to 30. Five years after the project was completed the speed limit was still at 30 in the databases. It finally went back to 45 a year or so ago.
  • edited March 2019
    Speed limit sign recognition will be welcome addition to my daily commute. Several expressways in Georgia have dynamic speed limit signs, which AP1 handled flawlessly. The difference can be from 35mph to 65mph. The problem here is that the car recognizes the default database speed as the highest speed and if the signs are set to the lowest speed you can not only get a ticket, in Georgia that would subject you to a "Super Speeder" ticket which is huge points possibly a loss of license and or trip to the jail if the officer happens to be in a bad mood.

    It is certainly not trivial.
  • edited November -1
    Then again there are many cases of AP1 misreading speed signs, so it's not a 100% solution. For example, there are cases where it reads the signs on the back of some trucks as a speed limit, or worse, reading interstate numbers as speed limits. I think in CA, parts of interstate 80 were read as 80 mph, where the limit is 65 mph!

    Tesla (and other automakers) will have to come up with a better solution than Mobileye reading / misreading signs. Some kind of database and sign reading with a dose of crowdsourcing is likely necessary.

    Then there are signs that are confusing like "15 mph when children are present". Does the camera look for children? Does it have a database of school hours for every school? Not sure the answer (although the safe solution is just go 15 mph).

    So the problem is far more complex than it seems on the surface.
  • edited November -1
    Who is actually responsible for updating the GPS speed limit databases? And how many are there?
  • edited March 2019
    “EVRider | March 8, 2019
    Who is actually responsible for updating the GPS speed limit databases? And how many are there?”

    IDK the answer but what I do know is that I have reported the same 45mph sign that both of our Tesla’s treat as 35mph (reported as a big and emailed from both cars) for over a year now and it still holds to 35mph today. So long story short....probably no-one is responsible and -0- people are working on it.
  • edited March 2019
    @Boonedocks: I wasn’t expecting that Tesla had anything to do with updating the speed limit databases, unless they have their own. By “how many are there” I meant how many databases.
  • edited March 2019
    They come from the major map companies. It's not a GPS database. GPS tells where on the map to find the speed limit. Tesla used to use Garmin but now they are using some free crowd sourced map I think. Its inaccuracy made me late for my nephews wedding last month. The turns were totally wrong. Never again will I trust Tesla navigation.
  • edited March 2019
    @murphy - I use the technique - trust but verify. I've never heard or seen of a nav system that is perfect in every situation. The key is to look at the total routing. Sometimes nav (again on any car) does strange things. On my last Lexus, on a 4 hour trip that I take regularly, it's routing would have made it an 6 hour trip. At least Tesla got that one right right. I've also seen Tesla routing that I knew a better route, although not a huge difference.
  • edited March 2019
    If we knew the exact source of Tesla’s speed limit data, maybe we could report errors more directly, rather than depending on Tesla to do so.

    @TeslaTap: Do you know?
  • edited March 2019
    @EVRider - Sorry, I don't know. In fact, if I was in charge of the speed data, I'd been taking AP1 speed detection with multiple hits - at least 5 per sign at a GPS location and use that to build a database, along with some additional validation. The sort of system that semi-automatically gets better with time. For all I know they may be doing this now, but haven't rolled out the resultant data yet.
  • edited March 2019
    Tesla drivers obey speed limits?
  • edited March 2019
    Was this on AP1 or AP2/2.5?
  • edited March 2019
    I had problems with AP1 misinterpreting signs in the earlier days, but not much in recent years. It used to be that it got conditional speed limit signs wrong. Now it's pretty good at those. It can't handle "end speed limit xxx" signs, which mean that the speed limit returns to the prima facie speed limit. But it can handle things such as a sign that says "speed limit 55" with a sign underneath it that says "trucks only or cars with trailers."
  • edited November -1
    I do not know for absolute certainty that this is accurate, but it was reported late 2017 that Tesla had switched to TomTom for speed limit data. If that’s the case, then best approach for getting database updated would be to report directly to TomTom.
  • edited June 2019
    I noticed in the latest Model 3 manual that it mentions speed limit signs. It doesn't say anywhere that it reads them but gives multiple warnings for speed assist that it may not work if speed limit signs are not clearly visible, if traffic signs don't conform to standards, if speed limit signs are concealed by objects, etc.

    Logically it might not work under those circumstances if the software doesn't even support reading speed limit signs, but it implies strongly that it does.

    I know that the manual isn't referring to Model 3s with HW1, and these are changes from what was in earlier manuals, so it follows that the software either reads signs, or they got ahead of themselves with the manual and it's coming soon. There's no reason that they should add this for the Model 3, but not the S/X with the same hardware as at least the earliest Model 3.

    I'll have to pay more attention if I drive the Model 3 near speed limit signs, but lately I've been driving it a lot less than the Model S, and mine is HW1.
  • edited November -1
    @Haggy: I think the mention of speed limit signs in the Model 3 manual is probably just left over from the original Model S AP1 manual, from which the Model 3 manual was eventually derived. The current Model S manual also has these references. I think the old AP1 speed limit sign recognition is probably coming back, but isn't here yet.

    Note that there are no HW1 Model 3s, they are all HW2.5 or later.
  • edited November -1
    All of that was added to the Model 3 manual and wasn't in the earlier release of it. The Model S manual has some of the same statements, but the manual applies to HW1 also, and there are the standard disclaimers about things varying by model.

    It wouldn't make sense to add things to the Model 3 manual unless they work with HW2.x, but didn't work with it before. I can't see any reason that it would be added for the Model 3 but not other models with the same hardware, given that there's no user interface issue.
  • I have a 2020 S and it is too frequently wrong about speed limits. Can a service tech fix this ?
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