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Speed Limit Signs not detected

Hello All.

I noticed something that I'm not really sure Tesla can fix or improve upon. I noticed this was I was on the road near Norfolk, VA on the Chesapeake Bay Bridge Tunnel. I noticed their signs were set a bit high and on the arm of the bridge. I noticed my model Y did not pick up or register the new speed limit. I adjusted accordingly, of course.

But I live in the Catskills area of NY and sometimes a speed limit sign is up high and it does not register either. There seems to be a pattern here, and I'm not sure if Telsa can even fix this since they can't control how high those signs are placed.

Another thing I noticed is the speed limit on some roads are set to 55 MPH, but when there are sharp S turns in the road going up or down, there are smaller signs posted to slow down to 40 MPH around those types of corners. If the car is in Autopilot, it will not slow down and take those corners at 55MPH, which makes it kind of scary. I think I did notice the car did decelerate once or twice. Will the car slow down if it detects too much centrifugal force?

I know the easy answer is to pay attention and change the speed. But the more we use Autopilot, the more we like it.

Is this something that runs better on FSD with regard to picking up the speed limit signs? I'm considering purchasing it now that my wife and I have learned to trust the tech more and more. I think at first it was just getting use to the phantom breaking or the warning tones and what they mean. I'm to the point where I am going to subscribe to FSD for a month, and if I like it, I'll buy it. Especially since the price will continue to grow.

The GPS only supplies location. The speed limits come from the Tesla Nav software. The Nav software is populated from various sources, Google map data, TomTom map data and perhaps OpenStreetsMap.org. It is hard to know and Tesla doesn’t explain where speed limits come from.

When Tesla ”sees” a speed limit sign it uses what it “sees” instead of the database speed limits.

It is a complex data problem. There are many threads in the forum on attempts to update incorrect speed limits with varying successes.
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