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Dangerous Cruise Control

I have 2021 M3 LR and on multiple occasions the cruise control brakes hard (phantom brake) on the highway. it happened for like the 15th time yesterday again.

I was doing 110km/h on highway and it suddenly slowed to a 70km/h. Why the hell can't the basic cruise control work properly on this car? I am not even talking about the Autopilot, just cruise control. Is it using Machine learning or something? The car brakes so hard that the front nose dives (hoping to make a video of it now). I had passengers in the car and they were all shocked.

If there is a truck behind me or there is black ice it will cause a major accident. I am afraid to use basic cruise control on this car now. This same road(s) I have driven using corolla on Cruise control and it has never braked on me.

Yes i did report software bug and to local Tesla techs through software appointment.

Sometimes it does it under a bridge, sometime at a fork, I just don't get it tbh.
 
Kinda makes me laugh when youtubers talk about "the beta" and how FSD beta is in beta so it will make mistakes. I want to say, you know what else is in "beta" just about everything else on this car lol. Just look at the list of stuff you can turn on its mostly all beta. The phantom braking hasn't been a problem for me in a while, you kinda learn where it's more likely to happen, I find when on autopilot or cruise control I hover my foot over the accelerator instead of over the brake, you shouldn't have to learn this and be ready for it all the time but with tesla it is what it is I guess.
 
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gangzoom

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May 22, 2014
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I've completely stopped using AP (have FSD option) due to phantom braking, its getting worse with every update that comes.

My passenger side window has also now stopped working, its the first time in 20 years of owning any car (including a 15 year old Mazda) I have encountered a failed power window.

Meanwhile Elon is laughing his way to the bank, Tesla is certainly the most 'unique' car company I have come across.
 
That is why I don't understand why Tesla does not give "dumb cruise control" option. Not like it is new. Tesla used to give this feature for customer not paying autopilot.

I think it must have to do with the fact that Autopilot is standard now and TACC is an integral part of AP. (When you disengage Autosteer by jerking the steering wheel while in AP, you end up in plain ol’ TACC.)

So then in order to have a “dumb” cruise control, you would either have to disable AP altogether (which I doubt Tesla would be inclined to allow, since it would highlight AP’s/TACC’s shortcomings), or Tesla would have to find an elegant/safe/intuitive way to manage having both a dumb cruise control and TACC on the same vehicle and ensure that drivers don’t get confused and accidentally think they’re in TACC when they’re actually in regular cruise control.
 
I think it must have to do with the fact that Autopilot is standard now and TACC is an integral part of AP. (When you disengage Autosteer by jerking the steering wheel while in AP, you end up in plain ol’ TACC.)

So then in order to have a “dumb” cruise control, you would either have to disable AP altogether (which I doubt Tesla would be inclined to allow, since it would highlight AP’s/TACC’s shortcomings), or Tesla would have to find an elegant/safe/intuitive way to manage having both a dumb cruise control and TACC on the same vehicle and ensure that drivers don’t get confused and accidentally think they’re in TACC when they’re actually in regular cruise control.
Considering the fact that the loaners (owned by Enterprise) were AP3-equipped Model S that had no AP or EAP, it's clearly possible to derate the features. Just dumb cruise control.

So this can be done in software, and I think it's a great idea to allow the driver the option (what if one camera goes down and AP/FSD are disabled?), but the icon should be very clear that CC is NOT running the safety and convenience features of AP/FSD.
 
Hmmm, I am regularly confused by the difference between what I experience in my MX compared to problems that others sometimes have. I can't recall the last time I had issues with fathom braking. I would guess it was about 8 months and over 7,000 miles ago. So I am still puzzled by the comments, but glad it isn't happening to me any more. Hopefully it will get fixed for others.
 
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I've completely stopped using AP (have FSD option) due to phantom braking, its getting worse with every update that comes.

My passenger side window has also now stopped working, its the first time in 20 years of owning any car (including a 15 year old Mazda) I have encountered a failed power window.

Meanwhile Elon is laughing his way to the bank, Tesla is certainly the most 'unique' car company I have come across.

When my driver side front window started acting up it took 2 trips the the service center plus a mobile visit for it to get fixed. Have had to get suspension fixed, my drivers seat sensor is now acting up, keeps thinking I've gotten out of the seat and back in even when I'm just sitting still, my drivers door has a popping sound when opening now, have has issues with condensation in pillar camera. Elon said the cars themselves were designed for a million miles, might of been designed for that but certainly not built for it ... maybe if you count miles on a flatbed? In fairness I still do like my car but most of the things that are suppose to make it amazing are half baked, which again in fairness in a lot of ways we do see improvements but in so many others just never improves. I am really trying to hold out hope for FSD but so many of the simple basic things haven't been fixed for so long I just don't know. I keep hoping maybe they aren't messing with the simple things because it will all be addressed in FSD, that's what I keep telling myself trying to stay positive but I think I might know better.
 
My model 3 (new in Sept 2020) also suffers frequent "panic attacks". I wonder if the underlying problem is a too-slow processor, as it frequently panics AFTER the event that seems to have triggered it.
This can be very dangerous: for example, when a bicycle approaches from a side road and would pass behind me, the belated braking could make it hit the rear of the Tesla. I now keep my foot over the accelerator to respond quickly when these events occur.
Surely it's time for a production version of Cruise to be introduced.
 
My model 3 (new in Sept 2020) also suffers frequent "panic attacks". I wonder if the underlying problem is a too-slow processor, as it frequently panics AFTER the event that seems to have triggered it.
This can be very dangerous: for example, when a bicycle approaches from a side road and would pass behind me, the belated braking could make it hit the rear of the Tesla. I now keep my foot over the accelerator to respond quickly when these events occur.
Surely it's time for a production version of Cruise to be introduced.
It's odd the divergence of experiences reported here, ranging from phantom braking to (now) late braking to working perfectly. Our '17 M3 and '20 MY are in the latter category.
 
It's odd the divergence of experiences reported here, ranging from phantom braking to (now) late braking to working perfectly. Our '17 M3 and '20 MY are in the latter category.
After watching the latest Karpathy CVPR '21 video, the comment about phantom braking in that video gave me a much clearer perspective and so I finally tested it out.

The exact quote from his talk is at the 25:30 mark --
But it starts like this: "Here's another example a fairly infamous example of slowdowns when there are cars going below a bridge"
The passing cars would get mis-associated to the stationary bridge, causing the braking.

Now, I originally though that the phantom braking was solely caused by the presence of a bridge/overpass (i.e. stationary object alone).
But that comment stood out as if it is a combination of leading/neighboring cars passing under a bridge.

I tested this out on our MY (w/radar) and sure enough, I could get it to tap the breaks on NoA almost every time when there were cars ~1/8 mile ahead passing under a bridge.
But passing the SAME bridge in the same direction 5 minutes later without cars, the car went through without a hiccup.

I do believe that they would have to spend a crap-ton of engineering resources to get good/useful fusion between radar+vision, so I am glad they are focusing on Vision alone.
Looking forward to more testing.
 

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