Spontaneous Lane Change

[Radlaw]

Recently downloaded ver. 2022.12.3.20. Today while driving with autopilot on a city street in the right lane of a 2 lane street, the left blinker suddenly came on and the car started moving to the left lane. I didn't want the left lane so I disengaged the autopilot and kept the car in the right lane. Has anyone else experienced this? Is this a defect that needs to be corrected or is it "normal"?

 

[MJB-CO]

This is/has been normal for FSD at least since its October 2021 release to Beta testers. The automatic lane changes can go both left and right on any road that has multiple lanes. Also watch out for changes into incorrect turning lanes.
When driving on highways we have the option to have FSD suggest lane changes and only change lanes if approved. For city streets we do not have that option.
When my 3 starts a lane change I don't want to make, I hit the reverse of the lane change indicator - that cancels the change, but it is annoying.
Hopefully we'll get the same option that we have for highway driving - only change lanes when the driver approves.

 

[Tam]

...Is this a defect that needs to be corrected or is it "normal"?...

I wouldn't call this "normal" but if you ask Tesla, it will answer that it's within the parameters or it works as designed!

 

[Radlaw]

I wouldn't call this "normal" but if you ask Tesla, it will answer that it's with the parameters or it works as designed!

Does it only do that when it's safe to make that lane change? It scared me the 1st time because I didn't know whether a car was in the left lane or not.

 

[UncleCreepy]

FSD has a bit of an attitude. You gotta be very clear what you want it to do. Like this:

 

[Tam]

Does it only do that when it's safe...

No. You are the safety driver. The beta is there for the purpose of testing.

I would not call beta as safe. No!

...It scared me...

That is the healthy attitude because if you let the beta does what it wants to do, bad things can happen fast (collision, traffic tickets, fatalities...)

...I didn't know whether a car was in the left lane or not.

Don't let the beta drives you. You need to drive it.

 

[Radlaw]

Got it! I like being in control, so my wife says

 

[MJB-CO]

Does it only do that when it's safe to make that lane change? It scared me the 1st time because I didn't know whether a car was in the left lane or not.

Yes, it will only make safe lane changes. My 3 actually kept me from getting hit at high speed twice by aborting lane changes (on a highway).
The problem is the lane changes are not always where I want to be, or logical in relation to the route plan.

 

[Dewg]

There are many times the software will tell you why it's changing lanes. Keep an eye out for that - it'll be in the traffic visualizations at the bottom (where it tells you to periodically move the wheel to make sure you're alert).

You may see things like "Changing lanes to keep on route" or "Changing lanes for maintaining speed" or "Changing lanes for obstacle/traffic cones". But there are also many times it changes lanes without telling you why at all.

I've found that if you go into NoA settings and disable automatic lane changes for speed, then it won't change lanes unless the route or construction calls for it. The downside is that FSD Beta will get you onto the freeway, and then just stay in the slow lane until it needs to get off the freeway. You can manually change lanes with the turn signal though - and it will automatically change lanes when needed for the route.

 

[MJB-CO]

This is/has been normal for FSD at least since its October 2021 release to Beta testers. The automatic lane changes can go both left and right on any road that has multiple lanes. Also watch out for changes into incorrect turning lanes.
When driving on highways we have the option to have FSD suggest lane changes and only change lanes if approved. For city streets we do not have that option.
When my 3 starts a lane change I don't want to make, I hit the reverse of the lane change indicator - that cancels the change, but it is annoying.
Hopefully we'll get the same option that we have for highway driving - only change lanes when the driver approves.

Correction : If my 3 starts a lane change I don't want to make I just cancel the change, I do not reverse it.

There are many times the software will tell you why it's changing lanes. Keep an eye out for that - it'll be in the traffic visualizations at the bottom (where it tells you to periodically move the wheel to make sure you're alert).

You may see things like "Changing lanes to keep on route" or "Changing lanes for maintaining speed" or "Changing lanes for obstacle/traffic cones". But there are also many times it changes lanes without telling you why at all.

I've found that if you go into NoA settings and disable automatic lane changes for speed, then it won't change lanes unless the route or construction calls for it. The downside is that FSD Beta will get you onto the freeway, and then just stay in the slow lane until it needs to get off the freeway. You can manually change lanes with the turn signal though - and it will automatically change lanes when needed for the route.

Note: Disabling Lane Changes for Speed in the NoA settings only disables the lane changes when on highways, it does not disable them in FSD Beta for street driving.

 

[sleepydoc]

You may see things like "Changing lanes to keep on route" or "Changing lanes for maintaining speed" or "Changing lanes for obstacle/traffic cones". But there are also many times it changes lanes without telling you why at all.

Except sometimes it says ‘changing lanes to follow route’ when it’s already in the correct lane and the proposed lane change is the wrong one!

 

[Dewg]

Except sometimes it says ‘changing lanes to follow route’ when it’s already in the correct lane and the proposed lane change is the wrong one!

That's due to current issues with the planner. I'm excited that more people got invited into the Beta (40K additional), but I wish they were brought in on a more stable version. 10.12 moved a few things to new neural nets, and reconfigured existing neural nets, and planning was one of those functions that needs tuning.

I'm hopeful the next version will tweak the NNs a bit and give us better lane selection.

 

[Supcom]

Except sometimes it says ‘changing lanes to follow route’ when it’s already in the correct lane and the proposed lane change is the wrong one!

The car changes lanes because the NN planner says to change lanes. I suspect the "follow route" notice is a fallback when there is no other reason specified.

 

[2101Guy]

That's due to current issues with the planner. I'm excited that more people got invited into the Beta (40K additional), but I wish they were brought in on a more stable version. 10.12 moved a few things to new neural nets, and reconfigured existing neural nets, and planning was one of those functions that needs tuning.

I'm hopeful the next version will tweak the NNs a bit and give us better lane selection.

They'll get it ironed out. Right now AP and NoA are nearly flawless for me. .....

Perspective. The two posts above show how one mans "nearly FLAWLESS" can be another man's "this cars ability to effectively and consistently change lanes on its own, is working poorly right now. To the point where I disable auto lane change".

LOL at "nearly flawless"..but has "current issues" and "needs tuning".

Elon is NOT paying you $12k man. Ease up..you are paying HIM

 

[Dewg]

Correct. AP and NoA are nearly flawless for me. I have disable lane changes for speed, so I don't have issues with it changing lanes when it thinks another lane is moving faster, but still changes lanes for route. I have exit passing lanes enabled so I make sure I'm not in the fast lane when it needs to change lanes for route into the fast lane. I have HOA access disabled so the system won't attempt to enter the HOA. Works well for me.

FSD Beta, on the other hand, does not take those settings on city streets, so it does change lanes based on it's neural net configuration. Recent changes to the planner, which was moved off old static code and more onto a neural net, need some adjustment and tweaking, which is evidenced by sporadic lane changes just before a route turn (people commenting that it changes to a left lane just before a right turn is required), and indecision on which lane is appropriate just before an intersection (such as the car deciding to go into the far left turn lane, and then suddenly changing into the #2 left turn lane at the last moment, sometimes taking up both lanes).

 

[Dewg]

Just to add clarity to the discussion, for those who are new to the Beta or did not know, there are currently two "stacks" of code running on the cars. There is the AP/NoA stack, which is older code, though periodically updated, and the FSD Beta stack, which is actively updated and where Tesla is focusing most of their development resources. When your car moves from a city street on FSD Beta onto a freeway/highway, the FSD Beta stack is relegated to the background and the AP/NoA stack takes over main processing. So your experience on one stack may be different from your experience on the other stack. You may read people talking about how their following distance changes when on the freeway vs when they are on city streets, as the two stacks handle those functions differently.

The goal is to merge the stacks into a single, unified code, where freeway/highway driving uses the FSD Beta stack instead of the older AP/NoA stack. This would have the effect of clearing up processing power, RAM, and storage as the system doesn't need to keep both stacks running at the same time (with one being shunted to the background when not needed). We don't know when that merge will happen. My guess is that FSD Beta users will be the first to get the new merged stack to test functions on freeways/highways for a few versions until it's ready to be released to non-FSD users. At that point the features will work for non-FSD users only on freeways/highways and discontinue when the driver or NoA exits the freeway. Those with FSD will continue onto city streets with the same stack.

 

[Supcom]

Perspective. The two posts above show how one mans "nearly FLAWLESS" can be another man's "this cars ability to effectively and consistently change lanes on its own, is working poorly right now. To the point where I disable auto lane change".

LOL at "nearly flawless"..but has "current issues" and "needs tuning".

Elon is NOT paying you $12k man. Ease up..you are paying HIM

Ahab, go back and reread those two posts you quoted. As usual, your obsession with Tesla has blinded you. The first post you referenced referred to FSD beta. The second referred to AP/NOA. You are comparing apples and whales.

 

[sleepydoc]

You are comparing apples and whales.

Apples...whales, it doesn't matter! What matters is if there's some way to spin, distort, remove context or otherwise find a way to speak negatively of Tesla. You people need to get over your need for truth, accuracy and perspective!