Welcome to Tesla Motors Club
Discuss Tesla's Model S, Model 3, Model X, Model Y, Cybertruck, Roadster and More.
Register

Tesla Model 3 and speed limit signs

I am looking at purchasing a M3LR. I currently have a Ford Focus (2016) which actually picks up speed limit signs very well generally.
I have read reports that the Model 3 in the UK is fairly poor at reading and adjusting to speed limit signs. Equally others say it is pretty good. I also know it uses GPS data but this is obviously not very reliable because of temporary speed limit signs and general accuracy.
What is the current situation on sign recognition and speed change?
How many speed signs does it pick up, such as national speed limit sign, small speed limit signs, overhead gantries etc.
 

Arran

Member
Feb 4, 2020
224
160
Southampton
My experience since owning from December as been overall very good. However it completely misses 100% of the time Smart Motorway Speed Limits on the Gantries, as well as Road-Works signs. Our local Motorway has 100's of 50MPH signs (average speed check), and it doesn't pick any of them up.
 
  • Helpful
Reactions: justinhow

VanillaAir_UK

Well-Known Member
Jun 17, 2019
8,968
6,565
Surrey, UK
The official operational domain for speed sign recognition is "local roads" which seems to be American for excludes motorways and many A roads.

The also has (as of last time I drove ours early November but unlikely to have changed much) a habit of mis reading some signs from adjacent roads, obeying signs far too late (when on TACC and autopilot/AP) and simply getting it wrong.

It does however use map based speed limits as a second point of reference - which may well be out of date. Getting speed limits wrong seems to be a common factor in some TACC/AP phantom braking events.

tl;dr - I expect the Ford implementation is much more complete. Don't trust the Tesla speeds - more of a convenience, when it gets them right.
 
  • Helpful
Reactions: justinhow

Dilly

Active Member
Feb 24, 2020
2,543
2,020
Norfolk
Can’t confirm motorways. There aren’t any in Norfolk.
Locally, A roads including dual carriageways pick up well as do B roads
It will also pick up a sign at a crossroads. Unfortunately, one I regularly pick up is a 30 which is the road opposite. I turn left onto the 50mph and have to wait for the next 50 sign for cruise to pick it up.
Generally, where signs are seen and recognised, cruise will adjust up and down automatically.
 
  • Helpful
Reactions: justinhow

Kenners

Member
Sep 29, 2019
226
210
London
I am looking at purchasing a M3LR. I currently have a Ford Focus (2016) which actually picks up speed limit signs very well generally.
I have read reports that the Model 3 in the UK is fairly poor at reading and adjusting to speed limit signs. Equally others say it is pretty good. I also know it uses GPS data but this is obviously not very reliable because of temporary speed limit signs and general accuracy.
What is the current situation on sign recognition and speed change?
How many speed signs does it pick up, such as national speed limit sign, small speed limit signs, overhead gantries etc.
Whatever you think now, once you get it you could get a software update that either vastly improves it or just destroys it, then fixes it, then brakes it. Rinse, repeat. That is the world of Tesla.
 
  • Like
  • Funny
Reactions: browellm and Jez_GB

GRiLLA

Active Member
Jul 5, 2020
1,145
1,196
UK
The feature works well, spots gateway and repeater signs reliably. I've occasionally seen issues where the gps database is wrong, but as soon as the car sees a sign it corrects. Hopefully this is being fed back to update the gps at some future point. There's also one spot locally in a 40 where the 30 limit from a side road has been twisted so the car picks it up by mistake. I also once had it read a 20 sign on an industrial estate, but there's no 30 to undo, it doesn't seem to be able to understand I'm back on a public road.

As per the release notes it's designed for 'local roads' by which them mean not motorways ...

“Speed Assist now leverages your car’s cameras to detect speed limit signs to improve the accuracy of speed limit data on local roads. Detected speed limit signs will be displayed in the driving visualization and used to set the associated Speed Limit Warning.”

I think a lot of the complaints are from people that would like it to work with motorway's with variable speeds or roadwork limits. I expect it'll get there at some point through a software update.
 

GRiLLA

Active Member
Jul 5, 2020
1,145
1,196
UK
Does anyone know why the don't enable if for motorways?
It's just not ready yet, it didn't read speed signs at all when I bought the car, now it does on local roads. They'll need to train their model to recognise the different types of motorways signage that are specific to the UK and be confident it's largely correct before they release.

There are lots (if not most) things on the car that are a work in progress, and perhaps will always be.
 

DenkiJidousha

Member
Sep 13, 2020
190
107
Scotland
We have a fair few 20mph signs when lights flashing for schools, and the Tesla always just treats them as a simple 20mph.

Likewise an A road with a 50mph truck limit sign, Tesla treated it as a plain 50mph limit.

Clearly it does not attempt to parse the full sign, just pattern recognition of the round bit.
 

Durzel

Active Member
Jul 17, 2019
3,939
2,910
Bath, UK
We have a fair few 20mph signs when lights flashing for schools, and the Tesla always just treats them as a simple 20mph.

Likewise an A road with a 50mph truck limit sign, Tesla treated it as a plain 50mph limit.

Clearly it does not attempt to parse the full sign, just pattern recognition of the round bit.
To be fair, I think it’s asking a lot of an AI system to understand nuances like that, particularly a limit that only applies when lights are flashing alternately, etc.

Maybe the UK Government ought to think about consistency with signs, e.g. make vehicle specific limits have a different coloured border, and school limits that apply all the time, or a motorised sign that only displays the roundel during active times.

They will need to think about this stuff with more and more vehicles moving towards automation.
 

Neilio

Member
Jul 8, 2020
994
626
Brentford
It has its moments but its nowhere as reliable as a Mercedes system.

Its unreliable enough that I can't trust it and that's kind of the point. I've been in quite a few twenty zones were it is telling me it's a thirty. Therefore it's not something you can rely upon despite it being correct about 90% of the time.
 
  • Helpful
Reactions: justinhow
It seems really odd to me that Tesla only started supporting speed sign recognition last year (as I understand). This technology is not new and some other manufacturers cars have been doing it for many years (Ford for one). Traffic sign recognition (including speed limits) is absolutely essential to any good autonomous driving system in which Tesla regard themselves as a world leader. Weird.
 

VanillaAir_UK

Well-Known Member
Jun 17, 2019
8,968
6,565
Surrey, UK
It seems really odd to me that Tesla only started supporting speed sign recognition last year (as I understand). This technology is not new and some other manufacturers cars have been doing it for many years (Ford for one). Traffic sign recognition (including speed limits) is absolutely essential to any good autonomous driving system in which Tesla regard themselves as a world leader. Weird.

A Mobileye patent seemed to be the biggest barrier - hence why it was on early Mobileye equipped models, but not later ones. Rumour has it that an alternate way has been found to achieve the same without infringing the patent.

Quite possibly:
Mobileye - thats a speed sign and it says 30
Tesla - that a cone, or wheelie bin, or 30 speed sign
 
I just find it odd that they have not yet programmed the car to slow down to the desired speed by the time the speed sign is reached, rather than reacting to it once passed. I'm sure it will come - perhaps already on city streets beta?
Yea - that would seem pretty simple. Off topic but what do you think of the Andersen A2 and app? Thinking of getting that one as well.
 
No matter how good or bad sign recognition is in Tesla today, an over the air update will change it in the future. (Not always for the better.)
Your Ford however will never change.
Owning a Tesla is a voyage of discovery. There is always something different.

If you have not yet had a test drive, get one, and then sign recognition will seem less important.
 
No matter how good or bad sign recognition is in Tesla today, an over the air update will change it in the future. (Not always for the better.)
Your Ford however will never change.
Owning a Tesla is a voyage of discovery. There is always something different.
If you have not yet had a test drive, get one, and then sign recognition will seem less important.
TBH it is mainly the fit/finish/quality and reliability issues that are making me hesitate about spending £45k on a Tesla.
  1. Bottom of Which! reliability survey ("Tesla must be doing something right to inspire such passion in its customers, but that something certainly isn't making reliable cars")
  2. Very low in JD Powers "JD Power scored Tesla vehicles the worst among 32 major brands in its annual quality study")
  3. Very low in US Consumers Reports ("Tesla’s overall poor performance in the annual study placed it second to last among the 26 ranked brands").
Now these are consumer lead feedback/reports so I don't think they can be dismissed as bias, which some Tesla owners seem to wish to do unless you are into conspiracy theories.
 
TBH it is mainly the fit/finish/quality and reliability issues that are making me hesitate about spending £45k on a Tesla.
  1. Bottom of Which! reliability survey ("Tesla must be doing something right to inspire such passion in its customers, but that something certainly isn't making reliable cars")
  2. Very low in JD Powers "JD Power scored Tesla vehicles the worst among 32 major brands in its annual quality study")
  3. Very low in US Consumers Reports ("Tesla’s overall poor performance in the annual study placed it second to last among the 26 ranked brands").
Now these are consumer lead feedback/reports so I don't think they can be dismissed as bias, which some Tesla owners seem to wish to do unless you are into conspiracy theories.

I was initially worried... but those surveys are based on 3 year old cars. Tesla admit they had production issues - it was the first time they had done a “mass production” car.

They were building in a factory that wasn’t designed by them. Tesla eventually set up a production line in a “tent” so they could streamline the production process, which increased speed and improved quality. (Munro was most impressed - apart from door panel gaps on one side)

This “tent” formed the blueprint which Tesla improved upon for the Shanghai and Berlin factories. Shanghai quality is much improved (and based on how fast they ramped up production - many of the USA bottle necks seem to have been solved).

Am I suprised that Mazda was at the top of the surveys, no as I’ve had 2 and never had a single issue in 6 years. Mazda and Toyota are the only make cars I’ve never had issues with. I’ve had 2 Alfas and 2 VWs, all had minor issues. The Jag was sold after a year (at the time it was too big for where I needed to park) and the Lotus cost me the more than all the others combined (but that was an amazing car to drive - so worth it)

Do I think Tesla will stay at the bottom once the 2020/2021 cars are being surveyed... not a chance. That’s why I’m picking up my most expensive car yet in just a few weeks.
 
TBH it is mainly the fit/finish/quality and reliability issues that are making me hesitate about spending £45k on a Tesla.

Sometimes you take a chance in life and you reap the award.

My SR+ is a year old now, has no fit/finish snags and doesn't rattle at all. We did 1,700 miles round the North coast of Scotland and back in October just before Nicola closed it down and enjoyed driving evey mile. Very steep hills are a wonder (you don't notice them) and the high regen coming down the other side reduced braking to zero and brought energy consumption to not far off driving on a flat road.

You will always read about complaints as often said here and its always possible to get a minger but the RH drive cars now coming from China should be far better built.

If you book a test drive, just be ready with the money as driving any of these cars is nothing like an ICE and to me is pure fun! :p
 
  • Like
Reactions: Jez_GB

Products we're discussing on TMC...

About Us

Formed in 2006, Tesla Motors Club (TMC) was the first independent online Tesla community. Today it remains the largest and most dynamic community of Tesla enthusiasts. Learn more.

Do you value your experience at TMC? Consider becoming a Supporting Member of Tesla Motors Club. As a thank you for your contribution, you'll get nearly no ads in the Community and Groups sections. Additional perks are available depending on the level of contribution. Please visit the Account Upgrades page for more details.


SUPPORT TMC
Top