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2021 Phantom breaking override?

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Hey Everyone,

It seems like it's a common issue for non-radar equipped Tesla's (I think the 2021 M3 and MY?) to have severe phantom breaking whether it's on Adaptive Cruise Control or Autopilot.

I was wondering if turning off "Automatic Emergency Breaking" will override whatever Cruise Control is seeing and let the car maintain speed? I know this is probably the worst possible solution to the problem but I am assuming that the phantom breaking occurs due to "Automatic Emergency Breaking" and turning it off should resolve the crazy phantom breaking but not affect speed changes in accordance with the vehicle in front of you.

Again I understand that this is not a good idea to turn off emergency breaking but I am almost at a point where I'm terrified to use even cruise control in the off chance of getting rear-ended despite the fact that I'm always on high alert and have my foot close to the accelerator.
 
Hey Everyone,

It seems like it's a common issue for non-radar equipped Tesla's (I think the 2021 M3 and MY?) to have severe phantom breaking whether it's on Adaptive Cruise Control or Autopilot.

I was wondering if turning off "Automatic Emergency Breaking" will override whatever Cruise Control is seeing and let the car maintain speed? I know this is probably the worst possible solution to the problem but I am assuming that the phantom breaking occurs due to "Automatic Emergency Breaking" and turning it off should resolve the crazy phantom breaking but not affect speed changes in accordance with the vehicle in front of you.

Again I understand that this is not a good idea to turn off emergency breaking but I am almost at a point where I'm terrified to use even cruise control in the off chance of getting rear-ended despite the fact that I'm always on high alert and have my foot close to the accelerator.
I’m less worried about rear-enders than the panic induced in passengers (and pets) when a phantom braking event occurs, especially passengers who have never experienced PB before and their resulting WTF moment. After 3 years for me it is less panic and more frustration and annoyance. Not sure how “common” phantom braking actually is, but I’ve had it on my radar-equipped June 2018 Model 3 since day 1, and still have it on v24.11 (not sure if that firmware uses the radar on radar-equipped cars). Since TACC has to be active for AutoPilot to activate, coupled with phantom braking on just TACC without active AutoPilot, I’ve assumed the issue is TACC. Then some folks including Elon posited that the removal of the radar or modifying software to not use it will eliminate phantom braking. Didn’t happen if the forums are any indication.

Curious about your hypothesis about disabling AEB: have you tried it? If so, any improvement to PB? I too would prefer to keep AEB enabled, but if that is the root cause, or at least a cause that I can control, of phantom braking, it would likely be a good trade off with passengers/pets in the vehicle.

Regardless, I still want a dumb cruise control setting option.
 
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FWIW a while back (on radar cars) testing showed that setting the emergency braking setting to normal or late significantly reduced phantom braking events compared to early. Dunno if it's relevant on vision only cars or not but might be worth a shot.

I've had my 3 for almost 3 years now, and can count on one hand with fingers left over the # of genuine "phantom" braking events I've had when the system was used where it's intended.
 
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...I've had my 3 for almost 3 years now, and can count on one hand with fingers left over the # of genuine "phantom" braking events I've had when the system was used where it's intended.
I believe you, and I believe the people who do have PB issues.

I want it explained why, by Tesla. What causes variation and what we can do about it. It can't be all down to camera cleaning, calibration, radar presence/absence, configuration strings, or driver misperception. Something is going on.
 
Phantom braking is probably not automatic emergency braking, unless you’re seeing a message indicating that AEB is in progress, so turning off AEB won’t help. If you do turn it off, that setting only lasts until your next drive.
Thanks for the reply. In all honesty, every time I experience phantom breaking, my eyes are glued to the road and I have never seen the screen so I don't know if it's the AEB or not.
I’m less worried about rear-enders than the panic induced in passengers (and pets) when a phantom braking event occurs, especially passengers who have never experienced PB before and their resulting WTF moment. After 3 years for me it is less panic and more frustration and annoyance. Not sure how “common” phantom braking actually is, but I’ve had it on my radar-equipped June 2018 Model 3 since day 1, and still have it on v24.11 (not sure if that firmware uses the radar on radar-equipped cars). Since TACC has to be active for AutoPilot to activate, coupled with phantom braking on just TACC without active AutoPilot, I’ve assumed the issue is TACC. Then some folks including Elon posited that the removal of the radar or modifying software to not use it will eliminate phantom braking. Didn’t happen if the forums are any indication.

Curious about your hypothesis about disabling AEB: have you tried it? If so, any improvement to PB? I too would prefer to keep AEB enabled, but if that is the root cause, or at least a cause that I can control, of phantom braking, it would likely be a good trade off with passengers/pets in the vehicle.

Regardless, I still want a dumb cruise control setting option.

It's actually the same for me. The passengers in my car get pretty scared and it's come to a point where they are like "fix it--calibrate it. do something to make it stop". I've tried disabling AEB and for now, there has been no PB. But in a couple of weeks, I'll be going about 200 miles and crossing the same points where I've experienced PB and around the same time so I'll be trying it again. Like you, I definitely prefer having AEB on but if there is anything that prevents phantom breaking I will use it for sure.

I love my M3 and if we could have dumb cruise control, it would absolutely change my life!
 
FWIW a while back (on radar cars) testing showed that setting the emergency braking setting to normal or late significantly reduced phantom braking events compared to early. Dunno if it's relevant on vision only cars or not but might be worth a shot.

I've had my 3 for almost 3 years now, and can count on one hand with fingers left over the # of genuine "phantom" braking events I've had when the system was used where it's intended.


I have both a Vision and Radar car. The radar car rarely phantom brakes. I just drove to the cottage with the vision car on a two-lane blacktop very straight highway for 1.5 hours. It phantom bakes on almost every coming car in the other lane. So much so it self-disabled autopilot halfway there, and I had to reenable at a stop sign. The vision car is really bad. It is upsetting my wife, she does not want to drive it with other people.
 
Most of my PB incidents happen on curvy hilly roads up and down Napa Valley. Since the beginning, Tesla said that AP was for driving on freeways, and I can see that might make a difference. I wonder where the PB incidents are occurring and if they don't happen on straight open roads or freeways. I have had some PB happen during morning and evening long shadows, but here again, it was on two lane roads with curves and hills, so I've never checked out what it does on the straights.

Does PB happen on freeways?
 
Most of my PB incidents happen on curvy hilly roads up and down Napa Valley. Since the beginning, Tesla said that AP was for driving on freeways, and I can see that might make a difference. I wonder where the PB incidents are occurring and if they don't happen on straight open roads or freeways. I have had some PB happen during morning and evening long shadows, but here again, it was on two lane roads with curves and hills, so I've never checked out what it does on the straights.

Does PB happen on freeways?
I drive 150 miles/day on 4 lane freeways and have ~100 PB incidents per week. These incidents are 99% when on a straight road with vehicles far in the distance and going over small rolling hills. And before my recent camera calibration I was getting ~400 incidents/week. You can change the PB behavior by changing the environment that the camera calibration happens. One other key piece, the 4 lane highway I drive is mostly empty and every time I am around other vehicles, there is NO PB....it is clear to me that Tesla has optimized TACC in traffic and it can't handle the "open road".

I also get the PB for oncoming vehicles on 2 lane roads.
 
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I drive 150 miles/day on 4 lane freeways and have ~100 PB incidents per week. These incidents are 99% when on a straight road with vehicles far in the distance and going over small rolling hills. And before my recent camera calibration I was getting ~400 incidents/week. You can change the PB behavior by changing the environment that the camera calibration happens. One other key piece, the 4 lane highway I drive is mostly empty and every time I am around other vehicles, there is NO PB....it is clear to me that Tesla has optimized TACC in traffic and it can't handle the "open road".

I also get the PB for oncoming vehicles on 2 lane roads.
Thank you, Recalibration has appeared to help.
 
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I had my TV MY on autopilot today for the first time and experienced phantom braking while approaching large road signs. Hopefully, as more data is collected by Tesla, they'll tweak the software to be more intelligent. Or not :)
 
I have had my Model Y for about 3 weeks and am experiencing the PB issue on a regular basis, about 3 times in a 20 minute commute. Sometimes they're very slight and speed resumes immediately but today it was a hard braking and there wasn't a car in front of me. It's very unnerving and I'm hoping there's a fix or explanation in the works.
 
You can change the PB behavior by changing the environment that the camera calibration happens
I've thought about doing a recalibration, but so far, only the SC has and they said "no issue" (of course). So what's the best way to recalibrate in order to reduce the incidence of PB?

I'm 2.5 years into owning Tesla's and I'd give anything to have the Dumb cruise control of my old Model 3 Standard Range back as TACC sucks because of PB, slow downs for no reason, panic on curves with traffic, etc... I will never ever consider buying / trusting FSD until this is fixed, which at this point is highly doubtful.
 
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I've thought about doing a recalibration, but so far, only the SC has and they said "no issue" (of course). So what's the best way to recalibrate in order to reduce the incidence of PB?

I'm 2.5 years into owning Tesla's and I'd give anything to have the Dumb cruise control of my old Model 3 Standard Range back as TACC sucks because of PB, slow downs for no reason, panic on curves with traffic, etc... I will never ever consider buying / trusting FSD until this is fixed, which at this point is highly doubtful.

Well I have reduced PB by calibrating the camera in my normal driving environment, which for me is very empty roads. It no longer goes crazy with vehicles near as my original calibration was in Ft. Worth. I have done probably 10 calibrations now with little change so it isn't that some magic situation fixes it, but it now more reasonable for the drive to work and back. I wish I had more for you but re-calibrating hurts nothing so experiment to find the PB you can live with....mine was reduced but didn't go away.
 
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Hey Everyone,

It seems like it's a common issue for non-radar equipped Tesla's (I think the 2021 M3 and MY?) to have severe phantom breaking whether it's on Adaptive Cruise Control or Autopilot.

I was wondering if turning off "Automatic Emergency Breaking" will override whatever Cruise Control is seeing and let the car maintain speed? I know this is probably the worst possible solution to the problem but I am assuming that the phantom breaking occurs due to "Automatic Emergency Breaking" and turning it off should resolve the crazy phantom breaking but not affect speed changes in accordance with the vehicle in front of you.

Again I understand that this is not a good idea to turn off emergency breaking but I am almost at a point where I'm terrified to use even cruise control in the off chance of getting rear-ended despite the fact that I'm always on high alert and have my foot close to the accelerator.
I have a 2018 M3 RW LR and on recent trip from SoCal to Denver area had several incidents of phantom breaking. Worst cases were when I was over taking a Semi on the left when we were both in a left hand curve. Car seems to believe that the truck is in front of me. Which I can understand maybe a little because it kind of is when you are both curving left as I overtake the truck. Everything is good until I get near the cab of the truck and then OMG. Still a bit jarring to say the least.
Is the “radar” to sensitive or focused too broadly in front of the car? Can and even should this be adjusted?
 
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Does anyone experience phantom braking when using HOV / express lanes on AP and traffic in the normal lanes is moving a lot slower?

Maybe this is either automatic emergency breaking (AEB) or perhaps even the Adjacent Lane Speed system?

There typically are divider sticks (which the car recognizes as cones) between the express lane and normal lanes, and I'm wondering if my car is panicking at the entry / exit points? Thing is, there is still an empty entry/exit lane between my car and the normal lanes with slow traffic.

There are no overpasses or other obstacles I can think of that would cause this sudden braking behavior.... so I think it has to do with Tesla's

Any way to prevent it from doing this?
 
Hey Everyone,

It seems like it's a common issue for non-radar equipped Tesla's (I think the 2021 M3 and MY?) to have severe phantom breaking whether it's on Adaptive Cruise Control or Autopilot.

I was wondering if turning off "Automatic Emergency Breaking" will override whatever Cruise Control is seeing and let the car maintain speed? I know this is probably the worst possible solution to the problem but I am assuming that the phantom breaking occurs due to "Automatic Emergency Breaking" and turning it off should resolve the crazy phantom breaking but not affect speed changes in accordance with the vehicle in front of you.

Again I understand that this is not a good idea to turn off emergency breaking but I am almost at a point where I'm terrified to use even cruise control in the off chance of getting rear-ended despite the fact that I'm always on high alert and have my foot close to the accelerator.
Right?! Me too! I AM afraid!! I threw my back out the first time it happened it was such a hard stop while going 65mph on the frwy with NO one in front of me. A big truck on the right set it off. Why wouldn’t it anyway move to the left to get away rather than break? There was no one to my left?
Did anyone answer your question about turning off the emergency breaking? I don’t see an answer… but I did see on a YouTube video you can hold the right button on the steering wheel and say “Bug report, Phantom Breaking,” after OT happens and it will send the info to Tesla
 
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I can confirm lots of phantom braking on a 2021 MY since the November (?) software update. For me, it's oncoming traffic, especially semi-trucks, on 2-lane highways that is a real problem. That said, if you have identified the cause, you can pre-emptively defeat automatic braking by pressing the accelerator. So now I'm cruising in autopilot looking for oncoming trucks and pressing the accelerator until they pass. So relaxing!