BBC News - Tesla investigated over 'phantom braking' problem
Tesla investigated over 'phantom braking' problem
The US government is investigating reports of Tesla cars braking unexpectedly on motorways.
www.bbc.co.uk
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Phantom braking to be investigated
- Thread starter Alex987854
- Start date
Good. It scares the life out of me every time it happens, which is at least once a week.
UkNorthampton
TSLA - 12+ startups in 1
I don't have Phantom Braking because I gave up using TACC in anything other than either empty roads or queues. But I am pleased that they are investigating this. Note however the report says M3 and MY from 2021 - is there a difference to earlier cars? My M3 is 2020 delivery and probably a 2019 build.
They're probably talking about the US Tesla Vision cars (no radar) which allegedly suffer from worse phantom breaking.
Good!
No accidents yet and it's not safe by any stretch of the imagination! I have had some very close calls thanks to this "feature".
Current UK M3 cars (including my M3P) have Tesla Vision with no radar and regular phantom braking.
PITA
Model 3 Performance
Good...
Does anybody else pat the steering wheel while saying "it's all right... it's all right..." then throttle to get past (usually a dancing skipping lorry avatar)
Does anybody else pat the steering wheel while saying "it's all right... it's all right..." then throttle to get past (usually a dancing skipping lorry avatar)
Likewise, TACC is something I simply don't use.
Disappointing, Mercedes "dumb" cruise control is more use.
Are you sure? I was pretty sure mine (late December LR) wasn't Tesla Vision, based on the allowed follow distances in TACC when I checked. I can't remember the details, but supposedly the minimum follow distance you can set in TACC is different on radar cars and Tesla Vision cars...
EDIT: Seems like the received wisdom was that if the minimum follow distance is 1, you have radar and if it's 2 or 3, you have Tesla Vision. (Of course, this may no longer be true with the latest firmware.) Will have to check mine again next time I use TACC.
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UkNorthampton
TSLA - 12+ startups in 1
Lots of usage and no accidents SEEMS like it's safeR. Unsettling but safeR. Only by knowing the stats - with TACC and without, averages for other cars would you know. I've known a couple of mates (in other cars) that hit cars in front of them for silly reasons. One said "Yeah but I thought the car ahead of me had gone, there was a big gap"
My guess is that stats are pro-computers, but human drivers are shocked and think they would have done better, while in reality they would have been more likely (over thousands of miles) to make a different, silly mistake with bigger consequences.
I also hope Audis are learning not to tailgate....
Tesla vision is US only. Apparently to remove the radar here they'd have to get it recertified, otherwise I'm sure they'd have done so.
Has anyone had issues with the TACC/autopilot changing its maximum set speed randomly/inappropriately which triggers the car to stamp on the brakes?
I wouldn’t say it’s phantom braking as I look across and the TACC speed would have changed from 70 to 50 on a 70 mph road yet I still have 70 on the speed limit sign. There are no lorries or dodgy bridges in sight.
It seems to crop up on the same place on the same roads, is it dodgy map data perhaps? Is there a setting I can change to fix it?
I wouldn’t say it’s phantom braking as I look across and the TACC speed would have changed from 70 to 50 on a 70 mph road yet I still have 70 on the speed limit sign. There are no lorries or dodgy bridges in sight.
It seems to crop up on the same place on the same roads, is it dodgy map data perhaps? Is there a setting I can change to fix it?
MrBadger
Badger out
It can be one of many things
Fleet speed on off ramps or intersections, incorrect map data, the car thinking it’s in the wrong place or taking a different route (fairly common near off ramps) and others including poor road sign recognition.
On motorways and major trunk roads the car uses map based data and not vision for speed limits, so it’s at the mercy of the map data. Like wise, vision speed limits are at the mercy of the road signs and the system is not clever enough to not recognise a speed limit in a side road as not applying to the road that you are on.
If you said where it was occurring that could be investigated.
Also stamping on the brakes or lifting off? Lifting off can feel quite aggressive at times but not the same as a full on stomping of brakes.
Fleet speed on off ramps or intersections, incorrect map data, the car thinking it’s in the wrong place or taking a different route (fairly common near off ramps) and others including poor road sign recognition.
On motorways and major trunk roads the car uses map based data and not vision for speed limits, so it’s at the mercy of the map data. Like wise, vision speed limits are at the mercy of the road signs and the system is not clever enough to not recognise a speed limit in a side road as not applying to the road that you are on.
If you said where it was occurring that could be investigated.
Also stamping on the brakes or lifting off? Lifting off can feel quite aggressive at times but not the same as a full on stomping of brakes.
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Sometimes the car reads the roadsigns that shows the lorry speed restrictions at 50mph as the road speed. I get it all the time, particularly here in Scotland where lorries on A roads are restricted to 40mph. I can watch the visual display pick up the lorry restriction sign and change the car speed.
Katic1972
Member
I have to say that so far at least Tesla have got this wrong. As Elon is known to say, and forgive me but I’m paraphrasing, words to the effect that if a driver has to interact then it’s a fail then us babying tacc, eap and fsd is failure.
I seriously doubt the wisdom of a vision only system. I’m sure the sw will eventually learn and get there but for now it’s simply not to be trusted.
I seriously doubt the wisdom of a vision only system. I’m sure the sw will eventually learn and get there but for now it’s simply not to be trusted.
I had thought that late '21 M3 cars were all Tesla Vision, but it seems that I was wrong and that this does only apply to the US. So thanks all for pointing this out. I did check my car and it is possible to reduce the following distance down to 1, which I understand is how to check whether there is a radar unit or not. I also understand that radar cars can have the cruise speed set as high as 90mph, whereas Tesla Vision is limited to 80mph. I haven't tried this one for obvious reasons, but the manual does give the maximum cruise speed as 150kmh, which is consistent with the car having a radar unit.
However, this makes my car's phantom braking problem even less forgivable. Radar based adaptive cruise controls have been around and implemented flawlessly by other manufacturers for many years, so why does a high tech firm like Tesla find this so difficult it can't get it right? My last two BMWs had adaptive cruise and I only suffered from one or two phantom braking incidents in a combined milage of over 60,000 miles, whereas my M3 slams on the brakes for no reason on just about every trip I make with TACC engaged.
interesting, thanks. I don’t think it’s engaging the friction brakes but when you have a warm battery, full regen is in effect stoping in the brakes.
I don’t think it’s anything like lorry speed limit signs and it’s happened a couple of times at exactly the same point, so I tend to just manual control through those sections.
Going across the top of Cambridge on the A14, in both directions. When going east bound it’s when the lane peals off to follow the A14 (rather than continue to the M11. West bound in a similar location, in the section between the science park and before the slip lane for the M11.
It happened yesterday on the M6 going north on the north side of Birmingham/Wolverhampton (sorry I can’t be more specific but it was before the miles current roadworks). The only thing I can think of is that those sections of road have been long term construction zones in the past with 50 limits.
When it’s happened it’s always been on a major trunk road, I don’t think it’s lorry’s as it’s done with with non in sight and their are not and side roads on these roads.
It’s just very ‘interesting’ when TACC decides to chop 20mph off your speed when you are in the outside lane with with traffic behind you.
As I said, the speed limit sign still read 70 and I’ve not noticed the nav drifting off onto any other roads (not that there are any).
Nolakai
Member
I wish we could opt to have a 'dumb' cruise control. I just want my top speed capped. That's it! The phantom braking business is ridiculous.
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