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Autopilot speed limit changes

Dilly

Active Member
Feb 24, 2020
1,345
995
Norfolk
I had a 30 mile “eyesight test” trip along with a picnic so did some more tests.

on a decent A road going straight into autosteer and staying in.

Automatic changes on autosteer took place over 7 miles without any intervention from me.
I was in a 60 limit with max speed set to 55. Came to a 40 limit and it dropped to 40. Entered a 60 limit and went up to 55. Entered a 50 limit and went down to 50 and lastly a 30 and down to 30.

Annoyingly, the one spot where I wanted to test TACC/autosteer on/off there were parked cars and traffic and couldn’t reliably test.

I also tried ‘chill’ mode. Well’ it’s sedate and economical and reminds me of most of my recent cars. Boring!!
 

Wol747

Member
Aug 26, 2017
666
271
Tea Gardens
Oops sometimes it feels like this is an M3 forum, apologies.

Accepted <g>

It does however bring to the fore what is a fundamental issue with the update system of Tesla.

We get updates all the time which make quite systemic changes to the car and its behaviour. The documentation of these is to say the least minimal. We see dozens of YouTube videos of people driving Teslas, all with different updates, and have to try and understand what our own car is capable of doing from these.

With such major changes especially to the autopilot functions I question whether we are in legal territory. Politicians seem to be like the deer in the headlights, taking all the industry hubris as gospel with little understanding of what is coming down the road (no pun intended).
 

Dilly

Active Member
Feb 24, 2020
1,345
995
Norfolk
One thing I did realise yesterday was that some speed limits which have only been in place for a year or so, are not recognised and the car uses the original limit.
Is that map or GPS at fault?
 

Wol747

Member
Aug 26, 2017
666
271
Tea Gardens
One thing I did realise yesterday was that some speed limits which have only been in place for a year or so, are not recognised and the car uses the original limit.
Is that map or GPS at fault?

Good question!

The incar indicated speed limits seem at times to be almost random. Sometimes they are wrong, and in fact some that WERE correct last week are now not so!
 

Jez_GB

Supporting Member
Dec 28, 2019
377
282
Nottinghamshire, UK
Reading through this thread I think I have witnessed most of the scenarios played out in my (non FSD) M3 LR. Unfortunately I have not documented the settings I have used and I keep changing them to try and find a Derek (happy medium :p).

I have come to the conclusion that while the speed setting and maintenance there of is systemically related to a combination of settings, external (detected) factors, hardware and software versions, the basis for the decisions and alterations the car makes is not something I can fathom, so I’ll just sit back and enjoy the ride and not worry too much more about it ;)
 
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Dilly

Active Member
Feb 24, 2020
1,345
995
Norfolk
Reading through this thread I think I have witnessed most of the scenarios played out in my (non FSD) M3 LR. Unfortunately I have not documented the settings I have used and I keep changing them to try and find a Derek (happy medium :p).

I have come to the conclusion that while the speed setting and maintenance there of is systemically related to a combination of settings, external (detected) factors, hardware and software versions, the basis for the decisions and alterations the car makes is not something I can fathom, so I’ll just sit back and enjoy the ride and not worry too much more about it ;)
Yup. Must be down to the wrong sort of leaves on the road or the wrong sort of clouds in the sky. Or even the wrong sort of dust on the cameras!
 

NorfolkMustard

Active Member
Apr 18, 2019
2,106
2,017
M3P w/FSD
Also, haven't seen this in the owner's manual before, is it recent?

It still doesn't say it reads speed limit signs, but even so it goes on to say what situations it may not be able to read the signs.

ftgyhuijkolp%3B.png
 

Mr Miserable

Supporting Member
Jul 8, 2019
4,097
7,584
UK
My hardcopy from last year says in the Limitations and Inaccuracies :
The speed limits stored in the GPS database are incorrect or outdated.

So yes this is a BIG change.
 

VanillaAir_UK

Supporting Member
Jun 17, 2019
6,936
4,478
Surrey, UK
Lets hope so.

If reliable, consistent and you are slowed to the limit by the time you pass the sign that will be a big one off the todo list. Icing on the cake will be variable speed limits and gantries etc. Hopefully they will also incorporate an offset for climatic conditions etc.
 

Dilly

Active Member
Feb 24, 2020
1,345
995
Norfolk
Well, I’m on 16.2.1. The on screen limits change later than passing the signs and the speed alters later still.
Tried again as road was quiet. Going out of autosteer, leaving TACC on and going back into autosteer knocks out auto speed change.
 

NorfolkMustard

Active Member
Apr 18, 2019
2,106
2,017
M3P w/FSD
I joined the club today :)

5 times the active max speed changed on its own. 4 times on single carriageway when the speed limit changed from 60 to 30. I thought it may have been because there was a car in front, but driving back through the same limit change with nothing ahead and it did it again

the 5th time was on a dual carriageway where an A road becomes a motorway. The limit doesn’t change but the max speed changed down to the 70 limit as I entered the motorway.

I still have speed assist set to relative +0
 

Dilly

Active Member
Feb 24, 2020
1,345
995
Norfolk
I joined the club today :)

5 times the active max speed changed on its own. 4 times on single carriageway when the speed limit changed from 60 to 30. I thought it may have been because there was a car in front, but driving back through the same limit change with nothing ahead and it did it again

the 5th time was on a dual carriageway where an A road becomes a motorway. The limit doesn’t change but the max speed changed down to the 70 limit as I entered the motorway.

I still have speed assist set to relative +0
Yes. It’s really weird and at the same time unintuitive and clunky. on my previous car, Lane keep remained active once engaged. If I indicated to change Lane it was temporarily disabled and then resumed once the indication was stopped. Having said that, it had no bearing on speed but you knew where you stood!

I hope it’s just work in progress. It would be much more intuitive and indeed safer, if you either run in autosteer or TACC rather than maybe both acting in unison or then again both acting independently.
 

Dilly

Active Member
Feb 24, 2020
1,345
995
Norfolk
The fact that (without FSD) once autosteer has been disengaged either by indicating and changing lane or just cancelling, re-engaging it doesn’t allow automatic speed limit changes and TACC takes over requiring manual speed changes, does this warrant a bug report?
Is it supposed to change speed automatically?
thoughts anyone?
 

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