Phantom braking (TACC/AP) [Not AEB]

[Katic1972]

That's all I wanted too

I get that the additional safety features are of value to some, and when I get my car I may come to appreciate them but I am most worried about the random phantom braking, not just for me but my wife will also drive the car so God help me if she encounters this issue. She will probably be able to deal with it and will lose all faith in the car.

I’m slightly less uncomfortable though as she seldom engages cruise as far as I am aware.

 

[init6]

That's all I wanted too

What? You want a cruise control that will plough into the car in front of you? How very 1980s

 

[init6]

I get that the additional safety features are of value to some, and when I get my car I may come to appreciate them but I am most worried about the random phantom braking, not just for me but my wife will also drive the car so God help me if she encounters this issue. She will probably be able to deal with it and will lose all faith in the car.

I’m slightly less uncomfortable though as she seldom engages cruise as far as I am aware.

They are of exceptional value in that they will stop the car from ploughing into the car in front of you when IT phantomly brakes.
I've had cruise control in almost every car for the last 20 years and TACC is by far much more useful than 'plain old cruise control' I've probably had 5 or 6 lapses of concentration where normal CC would have led to an accident. You've got to put all this talk of phantom braking into perspective. There are 40000+ Model 3 in the UK. If was as bad as the forums let you believe then the cars would be off the road.

Oh, and it will improve with time.

 

[Katic1972]

Yep. I get it. I do tend to use cc on non motorway routes like a roads. This to allow me to set the speed and not worry about police scotlands finest hiding behind a sign or engaging in other devious tactics to try and boost their pension pot. If we did have a non tacc for such situations then it’d all be great.

I really shouldn’t comment of course, I actually haven’t driven with tacc yet. So I’ll shurrup.

 

[MrBadger]

You soon learn the situations where there may be an issue and how to mitigate against the phantom braking - eg use of the accelerator overrides phantom braking and don’t use TACC when and where it is not appropriate. If you stay attentive and expect the unexpected, you should be OK. Just accept that it will happen from time to time, in the same way that something will happen from time to time that will mean that you have to take sudden evasive action in any car. If you are slow to react to TACC phantom brake, you will have a big slow down. If you are slow to take evasive action for something in any car, then you will probably have an accident. Neither are nice, so you drive prepared for them and they become non events. But if someone is tailgating you, probably best not to use TACC - its quite possible that the driver of the following car is not paying the same level of attention. Likewise, if you are not going to pay attention, don't use TACC or auto steer. The other thing to note is that the most common phantom braking events are relatively mild, reducing the car speed by only a few mph, equivalent to lifting off quickly and not needing any mitigating action - a bit like being driven by someone who doesn’t feather the accelerator for regen.

 

[NewbieT]

My biggest issue is the unpredictability- a new software update can change the behaviour. When you learn to cover the accelerator rather than cover the brake something is a bit wrong!

 

[squarepeg77]

2021.40.6 seemed to increase the occurrence of phantom braking for me. I had three braking events in about 20 miles on the M1 before I disengaged TACC and Autosteer.

I drove a few thousand miles on 2021.24.x, 2021.32.x and 2021.36.x and they were all much better behaved.

2021.40 got bad press in USA for phantom
braking too, which makes me think Tesla probably have changed something fairly significantly in this branch.

Tesla has a serious phantom braking problem in Autopilot

Tesla is seeing an increase in complaints over serious and dangerous phantom braking events plaguing Autopilot in the latest software...

electrek.co

 

[MrBadger]

My biggest issue is the unpredictability- a new software update can change the behaviour. When you learn to cover the accelerator rather than cover the brake something is a bit wrong!

I totally agree with this, but it is what we have and can be mitigated against. Most importantly, unlike other vehicles, behaviour can change from one release to another, for better or worse (I reverted to standard setting to avoid getting 2021.40 but still got .40.6 which is hopefully better), so historical performance cannot be used as an indication of future performance. So if anyone is considering ditching their order because of phantom braking, they need to consider that the general trend is that it does improve. However, the when and where to use is an important thing. If anyone wants to use TACC ignoring the scenarios in the manual (some excerpts below), then all bets are off. Its certainly something that takes a little time to learn.

 

[debrooker]

I totally agree with this, but it is what we have and can be mitigated against. Most importantly, unlike other vehicles, behaviour can change from one release to another, for better or worse (I reverted to standard setting to avoid getting 2021.40 but still got .40.6 which is hopefully better), so historical performance cannot be used as an indication of future performance. So if anyone is considering ditching their order because of phantom braking, they need to consider that the general trend is that it does improve. However, the when and where to use is an important thing. If anyone wants to use TACC ignoring the scenarios in the manual (some excerpts below), then all bets are off. Its certainly something that takes a little time to learn.

View attachment 739327View attachment 739328View attachment 739329

Might as well have just written do not use in the UK

 

[MrBadger]

Lots of places it can be safely used. Its also instantly controllable by steering wheel thumb control, disengaged/engaged by a slight movement of the stalk and can be overridden by the accelerator and brake. Its not going to drive the car for 100 miles on twisty or busy roads, but you learn when and where you override. Most of the exclusions would also apply to regular cruise controls and adaptive cruise controls.

 

[debrooker]

Think I'll be giving its first try when the family are not in the car - I get moaned at enough about my driving style with out random braking added to the mix

 

[d1217]

Lots of places it can be safely used. Its also instantly controllable by steering wheel thumb control, disengaged/engaged by a slight movement of the stalk and can be overridden by the accelerator and brake. Its not going to drive the car for 100 miles on twisty or busy roads, but you learn when and where you override. Most of the exclusions would also apply to regular cruise controls and adaptive cruise controls.

To be honest I wouldn't want it to drive me on twisty roads anyway, I still want to enjoy doing that myself while I can before Elon introduces cars with no steering wheel!

 

[candida]

Most of the exclusions would also apply to regular cruise controls and adaptive cruise controls.

I just don't agree with this at all: like many here I've used adaptive cruise and dumb cruise for decades altogether and my experience is that TACC is worse than either. I would go back to dumb cruise rather than continue using TACC.

 

[Wol747]

2021.40.6 seemed to increase the occurrence of phantom braking for me. I had three braking events in about 20 miles on the M1 before I disengaged TACC and Autosteer.

I drove a few thousand miles on 2021.24.x, 2021.32.x and 2021.36.x and they were all much better behaved.

2021.40 got bad press in USA for phantom
braking too, which makes me think Tesla probably have changed something fairly significantly in this branch.

Tesla has a serious phantom braking problem in Autopilot

Tesla is seeing an increase in complaints over serious and dangerous phantom braking events plaguing Autopilot in the latest software...

electrek.co

I have to agree with this: I've had my fair share of PBs but mainly just the odd few mph - nothing too dangerous. But the last week or so I've had three full-on PBs - licence test emergency braking style events - with absolutely no reason I could see, no cars near, no shadows etc.

 

[nunp]

Must give no confidence in using autopilot then - essentially too dangerous to use?

 

[Katic1972]

It’s a bit irritating, I get the complexity of the algorithm that they are desperately trying to model. When mastered it will be unworldly but for me, and I’m not alone, I/ we just want the option of a dumb cruise control.

To do so may admit defeat maybe so it’s great they are all in on making it good.

 

[MrBadger]

I/ we just want the option of a dumb cruise control.

Ironically, Tesla had it. When first Model 3's launched, there was both an SR and a SR+ variant, the latter is what we have today before the recent resignation. Not many SR's were ever sold, so its history was short lived but, iirc, it never had TACC or AP (although AP was an option in those days), just plain cruise control. So it does/did exist.

Personally I think if there was one extra could be incorporated, a speed limiter would remove the need for using TACC in most inappropriate scenarios.

New standard plus Model 3 come with TACC?

So a friend, a Volt owner, who is now thinking about buying a Model 3 asked me if with the new Tesla pricing structure will he need to pay extra to get TACC on the standard plus? Before last week you had to purchase EAP but what about now?

teslamotorsclub.com

 

[JonB]

Unfortunately I’m coming to the same conclusion - I use cruise control extensively and will 99% of the time have my young lad in the back so based on experiences on this forum I would be nervous to use this. Back to the original plan of an Ioniq 5 or BMW IX3 - gutted as would have loved the pace of the Tesla.

As regards the TACC on the IONIQ 5 (it has something like that), I was test driving it on autosteer and it tried to drive into the ARMCO barrier on a dual carriageway. Only once, so a glitch - but you'd be mistaken if you thought other EVs with the feature are perfect. Even my S-Max with intelligent cruise had phantom brake warnings (it would have applied the brakes but auto braking was disabled) and that's a Ford.

I think the point is that no computer system is perfect. And no, I am not I'm apologising on behalf of Tesla as they clearly have a lot of work to do.

 

[odyssey96]

I found recently phantom breaking has actually become less of an issue. I'm on 2021.40.6. the main scenarios I've identified to cover the accelerator is

- pedestrian crossing the road from the opposite side with the intention into wait in the middle of the road and wait for the traffic in my lane to subside

- approaching the beginning of a set of parked cars or parked bus in my lane

- any parked car in the set on the left happens to poke out into the lane i.e. crossing the striped parking boundary like a big truck

- end of parked car set on the left which will require a slight left turn immediately after, for example, when parking bays end and an island is in the middle of the road requiring you to circumvent it

- any cyclist in the lane, fine when there are clear lane markings for dedicated cycle lanes

I've been lucky to never experience phantom breaking on a motorway for some reason

 

[init6]

I found recently phantom breaking has actually become less of an issue. I'm on 2021.40.6. the main scenarios I've identified to cover the accelerator is

- pedestrian crossing the road from the opposite side with the intention into wait in the middle of the road and wait for the traffic in my lane to subside

- approaching the beginning of a set of parked cars or parked bus in my lane

- any parked car in the set on the left happens to poke out into the lane i.e. crossing the striped parking boundary like a big truck

- end of parked car set on the left which will require a slight left turn immediately after, for example, when parking bays end and an island is in the middle of the road requiring you to circumvent it

- any cyclist in the lane, fine when there are clear lane markings for dedicated cycle lanes

I've been lucky to never experience phantom breaking on a motorway for some reason

Those sound more like AEB issues. Not sure you should be using TACC in some of these instances.

As others have said, there is no guarantee that another brand will behave as well as you'd like either. I had a Jaguar that would throw on the brakes at a particular bendy junction. Once you get used to how a car will behave then it becomes more manageable.