Braking during automatic lane change

[Fursty Ferret]

Since updating to 2023.12 the constant micro-braking during a lane change has got exponentially worse, with the car now braking hard during 90% of lane changes (to the extent that for half a second the regen bar goes fully green). I don't know why it's doing it but it's been happening since December last year, but getting worse.

Can't imagine that it's a hardware fault as everything else works fine, but it's doing my head in, as well as making passengers sick. Is anyone else experiencing the same problem?

 

[M1tch]

Yes I have it on mine, but in a courtesy car at the moment and it’s almost non existent for a good 99% of the auto lane changes

 

[Fursty Ferret]

On those grounds do you think it’s worth raising a service request?

 

[M1tch]

Possibly. You know the answer will be “it’s a known issue which will be resolved during a future update”

 

[MrBadger]

Any difference in settings?

In a past thread, there were some discrepancies highlighted on lane change braking/stuttering when on TACC by some and not others. I think it potentially came down to one of the settings (possibly follow distance but may be wrong) and driving style (how close to vehicle in front when manoeuvre is started). It did seem to improve over time. I appreciate that this is auto lane change, but it could be similar, although I would expect driving style/how close to vehicle in front for same driver albeit in different cars to be fairly similar.

I have a sneaky feeling, based on several posts about difference in behaviour, that some of single stack changes are incorporated into the recent builds and that initially, some settings are being a bit over cautious resulting in some hesitant behaviour.

 

[Fursty Ferret]

Hmm. My follow distance is set to 4 at the moment and lane change on “mad max”.

 

[MrBadger]

Hmm. My follow distance is set to 4 at the moment and lane change on “mad max”.

Mad max only determines (in UK its suggestion that needs confirmation rather than an unconfirmed change) how aggressive it is in its choice of when to change lane rather than anything to do with the actual lane change itself. Mad max will be more aggressive in its choice to suggest a lane change, rather than a more relaxed approach which will stay in the same lane for more scenarios. ie, in some traffic mad max might suggest to change lanes more often had it not been MM.

Now if you accept the lane change in MM when close to the vehicle in front than perhaps you might, that may be an unintended consequence, but no different to do a non suggested auto lane change when closer to vehicle in front. If we had unconfirmed lane changes, then I could see it perhaps having a bearing on auto lane change behaviour, but in UK, timing of auto lane change is completely determined by driver, mad max mode or not.

 

[Pagemakers]

I’ve noticed this micro-braking too. Lane change either way and a momentary hesitation after the lane change before continuing. Irritating to say the least.

 

[Cardo]

I’ve also been experiencing the lane change hesitation for the past few months. It’s almost like the AP software is handing over the driving to a different lane change process and the handover isn’t particularly smooth. I also notice the hesitation at the end of the lane change, when I’m guessing control is being returned to the lane keeping process. Though, in my case, I haven’t noticed it getting worse. It’s certainly not a significant braking event, more of a slight hesitation.

 

[Overworked]

I have got it more noticeably than before with this update.

Have sent a service note with “please inform Texas”! Fully expecting the future fix notice - but if we don’t complain they will think all is ok

 

[Rob Smith]

Don't hold your breath, I think they are focusing on FSD.
As I understand it (from tweets lol, feel free to correct me) EAP looks to be code dependant for decision making and execution…and doesn’t even use all the cameras apparently (which might indicate where some issues lie). Elon recently said FSD12 should be end to end AI and not rely on falling back to (EAP or comparable?) coded routines for brake and steering.

 

[Pagemakers]

My NOAP took a massive turn for the worse when the car went vision only. It was much much better before.

 

[Pagemakers]

This is still happening on every lane change. It’s mildly unnerving and a tad uncomfortable.