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Autosteer and Adaptive Cruise Control problems

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New owner of a 2021 Model 3 LR. Performance Upgrade.

I just took my first 1200 mile trip with our new Model 3.
LOVE the car! Does everything well.

Except...

The Autosteer would drift quickly to the right whenever there was an exit or entrance lane starting
on the right of the slow lane. So, the auto steer determined that I suddenly was driving on a much wider
lane and so it would snap quickly into the new "middle". Then, it would snap back quickly into the
actual lane when the lane right line would return to its proper place. VERY disconcerting!

Also, the Adaptive Cruise Control would determine there was a non existent hazard in the road and rapidly
decelerate... dangerously. Sometimes the hazard was a change in the color of the highway - concrete with
a strip of black pavement for about 40 feet and then back to concrete. I think one time the car saw the shadows
of the trees that came across the road as a "hazard". Needless to say, it was again very disconcerting and dangerous!
Luckily, there was never anyone behind me when it happened. Which it did about 6 times on the trip!

Anyone else have these issues or is in my car?
 
...much wider lane and so it would snap quickly into the new "middle". Then, it would snap back quickly into the
actual lane when the lane right line would return to its proper place...

The system is not smart enough so it robotically centers itself between lane lines which can be inappropriate in a merging lane or a big lane. Humans would either hug the left side or the right side of a big lane so other cars can negotiate as needed.

It's unclear when it will be as good as humans in this scenario.

...Also, the Adaptive Cruise Control would determine there was a non existent hazard in the road and rapidly decelerate... dangerously. Sometimes the hazard was a change in the color of the highway - concrete with a strip of black pavement for about 40 feet and then back to concrete. I think one time the car saw the shadows
of the trees that came across the road as a "hazard". Needless to say, it was again very disconcerting and dangerous! Luckily, there was never anyone behind me when it happened. Which it did about 6 times on the trip!..

These are undesirable brakes or phantom brakes that are common in radar-equipped Tesla. Radarless Tesla cars were made starting 4/27/2021 in North America with the hope of escaping the crutch of radar phantom brakes.

A promise is a promise and Tesla will fulfill that in the future with your current radarless system.

 
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New owner of a 2021 Model 3 LR. Performance Upgrade.

I just took my first 1200 mile trip with our new Model 3.
LOVE the car! Does everything well.

Except...

The Autosteer would drift quickly to the right whenever there was an exit or entrance lane starting
on the right of the slow lane. So, the auto steer determined that I suddenly was driving on a much wider
lane and so it would snap quickly into the new "middle". Then, it would snap back quickly into the
actual lane when the lane right line would return to its proper place. VERY disconcerting!

Also, the Adaptive Cruise Control would determine there was a non existent hazard in the road and rapidly
decelerate... dangerously. Sometimes the hazard was a change in the color of the highway - concrete with
a strip of black pavement for about 40 feet and then back to concrete. I think one time the car saw the shadows
of the trees that came across the road as a "hazard". Needless to say, it was again very disconcerting and dangerous!
Luckily, there was never anyone behind me when it happened. Which it did about 6 times on the trip!

Anyone else have these issues or is in my car?
Lots (if not most) of us have these problems to one extent or another. I have a 2020 M3LR, so I have the radar. Auto steer works flawlessly for me on interstates, even as I pass exit ramps. On secondary roads, it also works quite swell but not flawlessly. Having said that, I rarely use it because I find it annoying to have to keep a certain amount of pressure on the steering wheel or get that annoying warning. I understand and respect the necessity of having to keep some pressure on the wheel, but still, why not just steer the car? It requires very little extra effort and I don't have to constantly think about applying that pressure. Regarding the M3's Adaptive Cruise Control, even with my M3's radar, it's not very good on secondary roads. I had a 2017 Volvo S60 and it's adaptive cruise control was considerably better than Tesla's, with far fewer instances of "phantom braking".
 
Yeah, no idea why Tesla doesn’t at least have detection in the steering wheel instead of requiring resistance like Audi and others have added. Maybe they’re pinning their hopes on the cabin camera, but that’s sure taking plenty of time.
 
New owner of a 2021 Model 3 LR. Performance Upgrade.

I just took my first 1200 mile trip with our new Model 3.
LOVE the car! Does everything well.

Except...

The Autosteer would drift quickly to the right whenever there was an exit or entrance lane starting
on the right of the slow lane. So, the auto steer determined that I suddenly was driving on a much wider
lane and so it would snap quickly into the new "middle". Then, it would snap back quickly into the
actual lane when the lane right line would return to its proper place. VERY disconcerting!

Also, the Adaptive Cruise Control would determine there was a non existent hazard in the road and rapidly
decelerate... dangerously. Sometimes the hazard was a change in the color of the highway - concrete with
a strip of black pavement for about 40 feet and then back to concrete. I think one time the car saw the shadows
of the trees that came across the road as a "hazard". Needless to say, it was again very disconcerting and dangerous!
Luckily, there was never anyone behind me when it happened. Which it did about 6 times on the trip!

Anyone else have these issues or is in my car?
What is your software version? I got my first update to 2021.32.21 about a week ago. I noticed a big improvement in the phantom braking thing. It may take up to eight weeks for the first update after taking ownership. Don't forget, this car will be "in development" for a while yet. Still the leader in AI in my book.

As far as following the off ramps that is what it is. I don't know it that will ever be improved. I see many of those around here will have a dotted white lines marking the RH side of the travel lane separate from the solid white line of the ramp lane. That seems to solve the problem. Bug your local DOT.
 
Vision only is much worse for phantom braking right now.

Hopefully it's better soon.
This is interesting... My car has a radar, but I thought that in some newer SW versions Tesla abandoned the use of the radar on all cars. If I am wrong on that, this explains why I have virtually no phantom braking while seeing a host of complains about it here on TMC coming from new Tesla owners. Well, I guess then that Tesla decided that the new owners have to experience the same pain with phantom braking the old owners had in early SW versions.

I think that the both the lane centering and phantom braking will improve with NN-trained FSD-based AP. Before that, it gets easier to predict the AP behavior with time spent in a Tesla. I usually know when to expect phantom braking (I'd say 80% of all cases, which are about 1 case in a week or two now) and either switch to the manual controls or get ready to adjust the accelerator pedal.
 
The offramp behavior seems based on if your state paints roads correctly or not.

Here, exits use dotted lines so the car knows it's not a single GIANT lane happening and I never experience this.

In states where they don't do that, seems to be an issue.

As I think alexgr is alluding to- the highway stack is supposed to get updated to use the same type of stack city streets (BetaFSD) is using today- and you might see this resolved when that happens as it seems to be generally smarter about dealing with lane markings (or lack thereof)
 
Actually, a single solid line is correct under the vehicle code as it indicates a lane you should not cross such as when you are near the gore point of an exit. And mine has done both of those behaviors since day one.
 
Actually, a single solid line is correct under the vehicle code as it indicates a lane you should not cross such as when you are near the gore point of an exit. And mine has done both of those behaviors since day one.


You're misunderstanding me.

The places I've seen this behavior reported there was NO line between the right-hand highway lane and the off-ramp.

So to a car going entirely by lane lines, it appears the lane suddenly doubled in size.

I've never seen it confused into thinking the lane got bigger when the lanes are actually marked by any line, dotted or solid.


Here, specifically, is what I'm talking about:

dotted.png



The dotted lines are optional.

Remove them, and it looks like your lane just got super big if only paying attention to the lane markings.

Include them and your car stays in its lane normally.

Not every place uses them.


The solid lines you talk about come much later/nearer the exit.
 
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The Software is 2021.11.104. Which I believe is not the latest. How do I update?
Make sure your car has a good WiFi connection when parked and then… wait.

I got my first update a month after taking delivery but it will vary based on what you have at delivery and when there is a newer version.

Also, I am on 2021.32.21 and about an hour ago I had my most severe phantom brake incident but it is in a spot where it has happened before. Guy in the pickup behind me was understandably not amused.
 
New owner of a 2021 Model 3 LR. Performance Upgrade.

I just took my first 1200 mile trip with our new Model 3.
LOVE the car! Does everything well.

Except...

The Autosteer would drift quickly to the right whenever there was an exit or entrance lane starting
on the right of the slow lane. So, the auto steer determined that I suddenly was driving on a much wider
lane and so it would snap quickly into the new "middle". Then, it would snap back quickly into the
actual lane when the lane right line would return to its proper place. VERY disconcerting!

Also, the Adaptive Cruise Control would determine there was a non existent hazard in the road and rapidly
decelerate... dangerously. Sometimes the hazard was a change in the color of the highway - concrete with
a strip of black pavement for about 40 feet and then back to concrete. I think one time the car saw the shadows
of the trees that came across the road as a "hazard". Needless to say, it was again very disconcerting and dangerous!
Luckily, there was never anyone behind me when it happened. Which it did about 6 times on the trip!

Anyone else have these issues or is in my car?
I had the same problem with adaptive cruise control in my 2021 Model 3 on a trip from FL to NY this summer. Does anyone know if Tesla is addressing this?
 
New owner of a 2021 Model 3 LR. Performance Upgrade.

I just took my first 1200 mile trip with our new Model 3.
LOVE the car! Does everything well.

Except...

The Autosteer would drift quickly to the right whenever there was an exit or entrance lane starting
on the right of the slow lane. So, the auto steer determined that I suddenly was driving on a much wider
lane and so it would snap quickly into the new "middle". Then, it would snap back quickly into the
actual lane when the lane right line would return to its proper place. VERY disconcerting!

Also, the Adaptive Cruise Control would determine there was a non existent hazard in the road and rapidly
decelerate... dangerously. Sometimes the hazard was a change in the color of the highway - concrete with
a strip of black pavement for about 40 feet and then back to concrete. I think one time the car saw the shadows
of the trees that came across the road as a "hazard". Needless to say, it was again very disconcerting and dangerous!
Luckily, there was never anyone behind me when it happened. Which it did about 6 times on the trip!

Anyone else have these issues or is in my car?
Yes, same issues. Mostly on secondary roads, so right now I don't use cruise on secondary roads.
 
New owner of a 2021 Model 3 LR. Performance Upgrade.

I just took my first 1200 mile trip with our new Model 3.
LOVE the car! Does everything well.

Except...

The Autosteer would drift quickly to the right whenever there was an exit or entrance lane starting
on the right of the slow lane. So, the auto steer determined that I suddenly was driving on a much wider
lane and so it would snap quickly into the new "middle". Then, it would snap back quickly into the
actual lane when the lane right line would return to its proper place. VERY disconcerting!

Also, the Adaptive Cruise Control would determine there was a non existent hazard in the road and rapidly
decelerate... dangerously. Sometimes the hazard was a change in the color of the highway - concrete with
a strip of black pavement for about 40 feet and then back to concrete. I think one time the car saw the shadows
of the trees that came across the road as a "hazard". Needless to say, it was again very disconcerting and dangerous!
Luckily, there was never anyone behind me when it happened. Which it did about 6 times on the trip!

Anyone else have these issues or is in my car?
It's not you.

I have disabled emergency braking (requires doing so every time I start the car) after AP decided a bridge was a hazard and slammed on the brakes doing 80 on 95 with someone tailgating me. I've also disabled allowing the car to take over steering even when not on autopilot.

But. AP still has a bug and will still incorrectly recenter when there's an ON ramp on the right.

Longer term apparent fanbois say "gotta break some eggs" ... I just call these bugs