You must be an attorney and a crazy one at that. People don't buy a new cars and have these issues. The person who delivered the car wasn't with me 5 minutes. These are major problems that Tesla has that needs to be addressed. They should have a class that explains You could be rear ended and killed at a high rate of speed using the cruise control when your car panic slows from 65 to 40 in 2 seconds!!!
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Cruise control inappropriately slamming on brakes
- Thread starter mckince
- Start date
Could you please address any of my questions? Thank you.
Also, the rate of speed is acceleration. Moving at a steady 150 mph is moving with a zero rate of speed. Hitting a curb at 5 mph is moving at a high rate of speed. I have not heard of many people being killed by hitting the curb at 5 mph.
If your answer to question #4 is 65 to 40 mph in 2s, that is 12.5 mph/s deceleration. This is 5.58 m/s^2 or about .57g. This is in excess of a typical driver maximum braking deceleration and not far from the maximum vehicle deceleration (M3 LR braking is 0.93 g at maximum).
Anyway, what happened after the car slowed down to 40 mph?
Also note, that no modern car accidents at 25 mph speed difference end up with fatalities to the best of my understanding.
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Amen!!! Good call. Thank you.Ha. Driving in Chicago... enough said.Assuming (based on your post) you didn't purchased the FSD and can't use Navigate on AP, the AP works rather flawlessly for me, especially on highways, except for phantom braking that happen once in a couple weeks now or so (and I can predict it nearly in all cases). If you feel uncomfortable, you always can stop sharing the car data.
While @alexgr 's post was a bit on the attacking side, it doesn't mean he wasn't on to something. Why didn't you go online before buying the car to look for "defects" or problems? Every car has complaints for something.
Now now, please no name calling cause it can go both ways... Tesla has been putting out Model S's for 9 years and Model 3's for 4 years. These issues you are seeing are not new, have been well documented and discussed, and yet they are still happening though to a lower extent, and there is still no mass panic among the population concerning it. If there has been serious rear end crashes due to phantom braking, don't you think there would be massive news coverage about it? The news loves to bash Tesla about everything.
No knowing about the issue doesn't excuse it, but it makes it known, well known in fact, but again if it was such a serious problem, there would be a lot more news coverage about it...And getting rid of the radar should help to reduce the phantom braking issue in a lot of scenarios. Concerning "stupid-bad" actions, it's all relative. If you do a navigate on autopilot on a completely empty highway, it will work pretty darn good, but as you add more and more random drivers, all with different driving styles and "stupid-bad" behavior themselves, then the Tesla is fighting against randomly occurring "stupid-bad" driving my the humans on the road. As more and more automated driving vehicles(all manufacturers) get on the roads, do you think it is going to get better or worse? I say it is going to get worse, but at some point it will get better as the percentage of automated driving reaches a critical point for the volume of traffic.
There should be a class, you want to go there...these forums have been discussing these issues for many many years. I know you probably just made the numbers up but 65-40 in 2 seconds is not really bad and someone following at an appropriate distance would have plenty of time to react to that. Even if they were a bit close, if they are paying attention they should have time to react. Also if YOU were paying attention YOU should have been able to react faster than that to press on the accelerator to stop the deceleration.(I know you are going to fight this point like all the others have in the past). Ohh and 65-40 in 2 seconds would result in -.57G's of deceleration.
@alexgr While your initial post that I and others complained about was a bit mean, clearly we are dealing with the same kinds of complaints that are meant only to complain and by people who don't really want to learn anything. And for the record, I didn't have any doubt of that since the beginning, I just start in to people a little slower...let them really stick their foot in their mouth first, haha.
Knightshade
Well-Known Member
They really aren't.
Other brands have far more significant braking issues with "smart" cruise systems, but they're still pretty rare.
There's gonna be near 2 million Teslas on the road by the end of the year- can you cite the "major" numbers of crashes caused by the issue you claim is super dangerous? (spoiler- you can't, because that isn't happening)
Did you actually measure this or are you just guessing from the "feel"? Because the couple times anyone has bothered to actually measure deceleration from phantom braking it was way less than that- it just "feels" strong because you don't expect it.
Almost as bad as phantom braking is the behavior of the follow cruise control which is too slow to react to the car accelerating in front of you and then too quick to come up it's ass when it's decreasing its deceleration rate. This has been a recent occurrence following a recent update. My guess is the new vision system has its limitations.
And they've been "writing that code" for the 6 years I've been driving my car #elondoesntcare #hesgotyourmoney
I have learned that this can be greatly reduced by switching to Chill mode. I always go to that in stop-and=go traffic (then back to normal once traffic opens up).
My car has been doing this since I got it over 2 years ago.
CheezyNachos
Member
I have had multiple "phantom braking" instances in my M3P and I have only owned it for 2 weeks / ~350 miles.
I have never had an issue with it in any prior vehicle I have owned. Most recently a 2021 Toyota GR Supra and a 2019 Kia Stinger GT2 AWD.
Hell, I would argue the Stinger's smart cruise control w/ stop & go and lane keep was in many ways just as good basic Autopilot (not as good at lane centering...I got more side to side bobbing, but better at things like not unexpectedly braking).
From a cruise perspective the Supra was also better as no phantom braking, but it did have horrible lane keep (I turned it off as it would get confused at off ramps and would forcibly try to keep you on the existing lane at times).
Hmmm. Maybe. At one point going downhill on a highway going around 75 I could see brake lights 5 cars ahead. I knew it was gonna slow down. The M3 on AP was speeding up to catch up after creating a 5 or so car gap. I knew this wasn’t gonna go well. When AP started braking it was late and anti lock brakes were skidding to slow down. This isn’t safe behavior. I have adjusted my use of AP based on its behavior and it’s use is going down.
Knightshade
Well-Known Member
Sounds like you switch cars really often, so maybe not a lot of data to compare.
But yes, worse in other cars.
For example-
Phantom Braking Leads to Mazda 3 Recall
A system designed to detect obstacles in the road ahead and automatically apply the brakes is acting up in current-generation Mazda 3 vehicles.
www.thetruthaboutcars.com
Or
U.S. probes 553,000 Nissan Rogue SUVs for unintended emergency braking
The National Highway Traffic Safety Administration (NHTSA) has opened a preliminary investigation into 553,000 Nissan Rogue sport utility vehicles after reports of their automatic emergency braking systems engaging without warning or an obstruction, the agency said on Thursday...
www.reuters.com
FWIW I've used Kias system (in a 2020 soul a relative owns that I've driven a number of times) and it was horribly bad at lane keeping- and even worse would often stop doing steering without telling you- unless you happened to look down and notice the green lines gone the only way you found out was when it began to drift out of its lane. Similar experience in a Kia rental I had in Atlanta last year.
Yes, I agree. The AP sucks at predicting far-distance slow-downs on highways when speed gradient is over 50 mph on half a mile or less. I think that Tesla simply assumes that traffic on highways never stops once it gets to 65-75mph. I always slow down the AP when I see a potential slow down ahead. It will improve (Edit: hopefully) with the FSD when it starts using the recognition of turn and stop signals of the cars around.
Note that it is NOT the AEB that is responsible for phantom braking in Teslas. The AEB is really cruel and dangerous last-resort braking. If anyone expereinces that in their Tesla, please know that is NOT what is typically called the phantom braking (which is more of a slow down for ghosts with no intention to stop) and is most likely a serious issue needed to be addressed at SC asap.But yes, worse in other cars.
For example-
Phantom Braking Leads to Mazda 3 Recall
A system designed to detect obstacles in the road ahead and automatically apply the brakes is acting up in current-generation Mazda 3 vehicles.
Or
U.S. probes 553,000 Nissan Rogue SUVs for unintended emergency braking
The National Highway Traffic Safety Administration (NHTSA) has opened a preliminary investigation into 553,000 Nissan Rogue sport utility vehicles after reports of their automatic emergency braking systems engaging without warning or an obstruction, the agency said on Thursday...
Knightshade
Well-Known Member
No, they haven't.
It's been less than 5 since they even introduced the original version of the current system and many features have been added or changed since then.
If your car is 6 years old it's AP1 and hasn't been in active development for many years.
CheezyNachos
Member
That is a weird twist of logic. What more data is needed then extensively using smart cruise systems? I would argue that exposure to multiple vehicles, for which none of them had this issue (anecdotally speaking), would provide a better point of reference.
I'll add the adaptive cruise on my prior Giulia as well. That car had many issues, but this was not one of them.
Knightshade
Well-Known Member
If you're switching cars so often you've had at least 3 or 4 since 2019 that's not really "extensive" testing.
I've got tens of thousands of miles and 3 years on my Model 3. I can count on 1 hand, with fingers left over, the number of actual phantom braking incidents.
And 0 of them have been so severe as to be dangerous- just unexpected.
Likewise, as mentioned Tesla is nearing 2 million cars on roads- and there's been no evidence presented of any significant # of accidents caused by what is being suggested as a MAJOR SAFETY ISSUE.
If it was one, there'd be evidence of it besides anecdotes.
I want to point out, however, that it didn't used to do that. It didn't use to create such gaps when cars in front would accelerate away and it would start slowing down earlier when approaching decelerating cars. Something in the last update or two changed behavior into what I think is less safe
I’m having the same issue, my 2018 S has hard braked on 3 occasions, at night, on the 3 lane route 75 while in the middle lane with vehicles on the left and right, none in front traveling at 77 on cruise.
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