Cruise control adapting to speed limits

Cruise control adapting to speed limits

I have a questions for the other model 3 owners about using cruise control. My understanding was that cruise would automatically reduce or increase speed depending on the speed limit and whatever offset you may have chosen. You didn’t have to touch the speed limit button on the screen.

That has happened exactly twice for me (both times, I went from a 70 mph limit to a 55 mph speed limit). Weird that it has happened twice, but never any other time. Is cruise control speed limit adjust supposed to happen automatically, or did I just dream that up? Thanks for any advice!


barb@duke | 30 mai 2019

Ours will consistently adjust to speed limit signs (plus the offset) when on autopilot.

BuffaloBillsFan | 30 mai 2019

Aaah . . . There’s the rub! I thought it would automatically adjust on just adaptive cruise control as well. Tanks for the input!

rwade2666 | 30 mai 2019

if the offset isn't indicated but the speed limit is correct just touch the speed limit sign and the offset will update.

EVRider | 31 mai 2019

TACC does not adjust your speed based on speed limit changes, and Autosteer doesn’t either if you’re on a limited access highway. If the car doesn’t think you’re on a limited access highway, Autosteer will be limited to the speed limit plus speed offset (up to a maximum of 5mph) and will adjust your speed accordingly.

walnotr | 31 mai 2019

I sadly haven’t haven’t been able to drive my car for a couple of weeks, but have noticed more instances of the speed adjusting on both TACC and autosteer/NoA. What I can’t remember at this time is if it was only on controlled access roads or on some surface streets as well. I tend to use it as much as possible hoping to be part of the solution to FSD so my experiences maybe a little blurred in my not so young brain. I do recall one instance of the car slowing as it approached a lower speed limit sign and was pleasantly surprised when it happened.

cafutter | 31 mai 2019

Be aware, the speed limit it thinks is correct, is sometimes incorrect. My experience is near the Maryland -DC line on my way to work. My car thought the speed limit was 25 mph when in fact is was 35 mph. I reported it several times as a bug report and eventually it corrected (whether or not it was because of my I my reporting, is unclear).

CharleyBC | 31 mai 2019

I have noticed the set speed reduce, but only when using Autosteer, not just TACC. And “notice” is pretty conspicuous, as it puts a message on the screen about 5 above the limit for Autosteer.

As @cafutter said, it’s annoying when the speed limit data are wrong. It forces you to choose to continue to use Autosteer while driving below the limit, or disengage Autosteer and go your desired speed. (“Bug report: posted speed is 65. Car thinks 55.”)

Techy James | 31 mai 2019

@CharleyBC, I agree it's annoying when the Posted Speed Limit and the Map Data Speed Limit don't match, but this will always be a problem until the Camera Recognition is able to identify Street signs. What I find funny about the Map Data, is on one side of the street the data will be off, but when your going other way the map data is correct.
As for the part about using AP or not because the Speed limit, I only noticed AP being affected is if the road is not a Limited Access Road. On Limited Access Roads/Highways I have never noticed it adjusting the speed automatically except occasionally in cases where the road has a hard curve, then it slows for the curve then speeds back up after out of the curve. Now on Limited Access Roads, then AP is limited to 5 over the expected Posted Speed Limit.

BuffaloBillsFan | 31 mai 2019

Thanks for the feedback everyone.

xavier | 5 octobre 2019

Please add the cruise control function without auto steering with the function of regulating the speed by the signals, I have a 2017 Mercedes and it does, it is perfect for not catching speeding fines.

andy | 6 octobre 2019

Difficulty is that the speed limits in the navigation database are very often inaccurate. In the UK we also have the added complication that mandatory speed limits change in real time - gantries are used to adjust the speed limit and display it depending on the level of congestion that's detected and any incidents that occur.

In the Leaf I was able to use the speed limiter and then adjust it at each gantry and speed limit change The car also read speed signs. This gave a double assurance that you had set the correct speed. In cruise control in the Tesla the car sets a reference speed of what it thinks the current limit is according to the database. As soon as you touch the brake then you've lost what you previously set. I've found that you can, if you hold the accelerator down and maintain. speed that way, engage cruise control with the car holding the current speed until you have manually changed the maximum down to the current speed and then released the accelerator - but it is a lot of work.

Another downside of relying on the navigation database and variable speed limits is that you can't reply on the chime to warn you when you what the limit as the chime is linked to the navigation database and not the current local conditions. In a car that accelerates so smoothly, combined with the cameras that are on many gantries, this makes driving on motorways much, much harder and stressful work that it need be.

All that's needed is to introduce and implement a speed limiter in the way that other manufacturers do. The driver can then make decisions pending the time when the car can read and act on he myriad of confusing signage that we have.

SolArray | 6 octobre 2019

My experience with EAP is this - when going to reduced zone (e.g. from 55 zone to 45 zone), the adjustment in "setting and actual driving speed" are reduced. However, when returning from 45 zone to 55 zone, the speed limit sign icon shows the change back to 55 zone, but the "setting and actual driving speed" for EAP don't increase. I have to do that manually - with R scroll wheel.

andy | 6 octobre 2019

It’s good that it works that way as we don’t have a speed limiter. The way it works allows the driver to check the speed limit change is correct and then increase the speed.

Hugues1965 | 7 octobre 2019

That's odd. I never managed to have my car slow down when going to a speed reduced zone. It does detect it, i can see it on screen, but my speed stays the same. Is there a parameter that needs to be set for this to happen ? I'm using speed and lane assist, but not NoAP.

n7vdr1 | 7 octobre 2019

you have to be in some form of auto pilot. tacc will not reduce speed.

walnotr | 7 octobre 2019

I have experienced speed limit adjustments while on AP. For some time now. What has recently changed is the resume speed after going through a speed zone, returns to the preset speed before the reduced speed. .i.e, cruising along with a set speed at 62 MPH, enter a 45 zone, car adjusts speed to 50 MPH, exit 45 zone back to 60 MPH and speed resumes 62 MPH set point. This seems to be new in 32.11.1. Or at least I’ve never encountered it before.

EVRider | 7 octobre 2019

The speed limit adjustments only happen when using Autosteer and when the GPS data determine that you’re driving on a “secondary” road (which is often incorrect). In that case you’re limited to the speed limit plus 5mph. If the car thinks you’re on a limited access highway, it doesn’t slow down for speed limit changes.

It has always worked this way, so it’s not a V10 change.

mike.occhis | 7 octobre 2019

How does one make a bug report?

jdbeth | 8 octobre 2019

mike.occhis, push the button on the right on the steering wheel, hold it in, say"but report" and then state the problem.
You will not receive any type of confirmation afterwards, but I have gotten my issues fixed within 24 hours every time I used it.

FISHEV | 8 octobre 2019

"The speed limit adjustments only happen when using Autosteer and when the GPS data determine that you’re driving on a “secondary”"@EVRider

It happens in regular AP all the time. An artifact of the self driving tech that plagues Tesla's AP system.