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Speed Limit Signs not detected

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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.
 
@howardnj

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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Slow down to 40 signs are almost all informational and not the actual speed limit. They are always in yellow if informational and not the actual speed limit.
In Virginia, yellow advisory speed limit signs:

"Advisory Speed: This sign indicates the maximum safe speed for a highway exit."

So in VA it is the actual speed limit. The car ignores these signs even with FSD. No bueno.

On my way to work every morning I take a 360 degree exit off a 45 mph divided road onto the interstate. It goes through the first 270 degrees with a limit of 30 mph, then there is a straight portion on an overpass to go over some railroad tracks (this section is part of a divided highway with a 45 mph speed limit, white signs), then a sharp, hard 90 degree loop to merge onto the interstate. This 90 degree turn is strongly banked the wrong way and is marked at 20 mph with a yellow sign.

The car comes around the first 270 at 45 mph, then about a quarter of the way on the straight portion it picks up the 65 mph speed limit of the interstate, not the 45 mph of the section it's on (which isn't marked, the white 45 mph speed limit sign is well past this short section). It accelerates HARD toward 65 and hits the opposite-banked hard right still accelerating. If I don't intervene it would crash.

Maybe its interpretation of yellow speed limit signs should be customized for the laws of individual states.

It also doesn't recognize stop lights when they are in an unusual position. I go through a guard gate, there's a red/green light near the ground on the right of the gate across my lane. The car doesn't recognize the light or the gate itself and would bust through the gate at 25 mph without intervention.

I keep sending clips in to the Mother Ship and trust these bumps will be ironed out in future updates.
 
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In Virginia, yellow advisory speed limit signs:

"Advisory Speed: This sign indicates the maximum safe speed for a highway exit."

So in VA it is the actual speed limit. The car ignores these signs even with FSD. No bueno.

On my way to work every morning I take a 360 degree exit off a 45 mph divided road onto the interstate. It goes through the first 270 degrees with a limit of 30 mph, then there is a straight portion on an overpass to go over some railroad tracks (this section is part of a divided highway with a 45 mph speed limit, white signs), then a sharp, hard 90 degree loop to merge onto the interstate. This 90 degree turn is strongly banked the wrong way and is marked at 20 mph with a yellow sign.

The car comes around the first 270 at 45 mph, then about a quarter of the way on the straight portion it picks up the 65 mph speed limit of the interstate, not the 45 mph of the section it's on (which isn't marked, the white 45 mph speed limit sign is well past this short section). It accelerates HARD toward 65 and hits the opposite-banked hard right still accelerating. If I don't intervene it would crash.

Maybe its interpretation of yellow speed limit signs should be customized for the laws of individual states.

It also doesn't recognize stop lights when they are in an unusual position. I go through a guard gate, there's a red/green light near the ground on the right of the gate across my lane. The car doesn't recognize the light or the gate itself and would bust through the gate at 25 mph without intervention.

I keep sending clips in to the Mother Ship and trust these bumps will be ironed out in future updates.
"In Virginia, yellow advisory speed limit signs:

"Advisory Speed: This sign indicates the maximum safe speed for a highway exit."

So in VA it is the actual speed limit. The car ignores these signs even with FSD. No bueno."

Can I Get a Ticket for Exceeding an Advisory Limit?

Advisory speed limits are not a legal speed limit; only the standard white speed limit signs carry the force of the law. Therefore, you cannot get a speeding ticket for disobeying an advisory speed limit sign. Yellow signs are simply a warning to drivers of a change in road conditions that may make their current speed dangerous. The number is usually based on the physics of the road, taking into account things like centrifugal force (around a bend) and angular momentum (at the top of a hill).
 
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"In Virginia, yellow advisory speed limit signs:

"Advisory Speed: This sign indicates the maximum safe speed for a highway exit."

So in VA it is the actual speed limit. The car ignores these signs even with FSD. No bueno."

Can I Get a Ticket for Exceeding an Advisory Limit?

Advisory speed limits are not a legal speed limit; only the standard white speed limit signs carry the force of the law. Therefore, you cannot get a speeding ticket for disobeying an advisory speed limit sign. Yellow signs are simply a warning to drivers of a change in road conditions that may make their current speed dangerous. The number is usually based on the physics of the road, taking into account things like centrifugal force (around a bend) and angular momentum (at the top of a hill).
Correction noted, thanks. I'm not really so concerned about getting a ticket as I am being in an accident because the car doesn't recognize posted maximum safe speed limit signs and flies around a 20 mph curve at 65 mph.
 
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I know the easy answer is to pay attention and change the speed
Seriously: Yes. Drive your car, don't let your car drive you. FSD isn't ready for prime time. These are some of the reasons why, so don't rely on it.

Sometimes it's as simple as an overgrown tree or shrub that obscurs the sign, sometimes it's a different height, or a temporary speed change. Drive your car.
 
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Seriously: Yes. Drive your car, don't let your car drive you. FSD isn't ready for prime time. These are some of the reasons why, so don't rely on it.

Sometimes it's as simple as an overgrown tree or shrub that obscurs the sign, sometimes it's a different height, or a temporary speed change. Drive your car.
FSD is doing really good but I agree it isn't ready for the masses. We'll see after the next update but there's still a couple things it has trouble with, mainly complex intersections.
 
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I am also having an issue with speed limit signs being ignored. It is always on the interstate where the speed limit increases in my area from 60 to 70 mph. Sometimes it misses the first sign and sometimes the first 2 or more. I set up a repair appointment with Tesla, they had my car for 3 days and said they could not recreate the issue or find anything wrong with the system. I picked up the car and on my way home that very day where the speed limit changed it did not detect the first 4 signs. At the 5th sign more than 5 miles from the speed zone change the car finally detected and registered the correct speed limit. I tried this from the outside lane and the center lane with the same results. I contacted Tesla and made a new appointment. I was contacted by them and they said they did a remote diagnostic on the software and hardware and found nothing wrong so there was no need to bring the car back. I don't have FSD but it doesn't make any difference if I am using autopilot or not I have the same issue. My concern with this is since the camera vision is part of the safety system on the vehicle other malfunctions in the camera vision system could be much more serious than just not detecting a speed limit sign.
 
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Not picking up the signs is a major problem in rural Colorado roads. It's clearly not the placement of the signs. There is some logic where the car ignores the signs because they are not quite consistent with what is in the car speed limit database. Very frustrating!
 
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@howardnj

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.
They actually do explain it...

 
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They actually do explain it...

Ah, no. The article says “Now this new update gives us some answers.”

The problem is Tesla assigns a speed limit to all roads. My car even thinks that my driveway is 25 mph.

Not all roads have speed limit signs or the speed limit signs are spaced very far apart.

How every foot of all roads have an assigned speed limit is not clear from Tesla. Nor is it easy to “fix”.

To a common degree States set standard speed limits for various roads, state roads, county roads, city roads. But these vary with local jurisdictions.

It would be helpful if Tesla explained how speed limits are set if the car does not see a speed limit sign. Then we could fix the places where generic speed limits are incorrect.
 
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