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Phantom braking and active safety features

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I understand phantom braking significantly constrains the vehicle’s cruise control functionality. That’s frustrating (my 2016 Civic has great adaptive cruise control). But I’m much more concerned about what this issue means for the vehicle’s broader active safety features beyond cruise control (emergency braking, collision warning, etc.). Are current owners experiencing issues with their active safety features?

It seems the IIHS is currently testing the 2021 Model Y without radar. Hopefully we’ll learn more soon.
 
I did a 1,000+ mile trip over the Thanksgiving holiday and had 3 instances of phantom braking. In all the 3 instances it was the same scenario - I was attempting to pass a large truck.

Watching the visualization on the screen, you would see the truck to my right. As I go closer to the front of the truck, you would see the truck begin to jump about on the visualization screen. At some point it would jump across the line into my lane and the car would slam on the brakes. To me, this has nothing to do with radar, this is a vision problem. When an object to the side of the car does not completely fit within the camera's frame, the car is losing the ability to accurately place it in 3D space.
 
I did a 1,000+ mile trip over the Thanksgiving holiday and had 3 instances of phantom braking. In all the 3 instances it was the same scenario - I was attempting to pass a large truck.

Watching the visualization on the screen, you would see the truck to my right. As I go closer to the front of the truck, you would see the truck begin to jump about on the visualization screen. At some point it would jump across the line into my lane and the car would slam on the brakes. To me, this has nothing to do with radar, this is a vision problem. When an object to the side of the car does not completely fit within the camera's frame, the car is losing the ability to accurately place it in 3D space.

That's interesting, and the first I've seen anyone mention that as a reason. It does make sense, though. And your model still has radar, so that is even more interesting to me. And, like you said, it seems like a vision issue, and obviously having radar isn't helping here. I wonder what the FSD beta would have looked like for you in the same scenario.
 
Same had 600 mile trip i had maybe 4 phanton braking events 2 were me trying to pass a semi and the other 2 events was actually going over a hill

The semi description above sounds accurate to what i saw

And as far as the 2 events over the hill im pretty certain it was the camera thinking its a drop off or aimply it can’t see over so it brakes
 
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Same had 600 mile trip i had maybe 4 phanton braking events 2 were me trying to pass a semi and the other 2 events was actually going over a hill

The semi description above sounds accurate to what i saw

And as far as the 2 events over the hill im pretty certain it was the camera thinking its a drop off or aimply it can’t see over so it brakes

I have radar equipped cars, I got the "over the hill" slowdown yesterday morning coming back from a drive. that one doesn't bother me so much.

I am regularly around semis, however, and never have any issues at all. Gotta be the vision only is glitchy
 
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I did a 1,000+ mile trip over the Thanksgiving holiday and had 3 instances of phantom braking. In all the 3 instances it was the same scenario - I was attempting to pass a large truck.

Watching the visualization on the screen, you would see the truck to my right. As I go closer to the front of the truck, you would see the truck begin to jump about on the visualization screen. At some point it would jump across the line into my lane and the car would slam on the brakes. To me, this has nothing to do with radar, this is a vision problem. When an object to the side of the car does not completely fit within the camera's frame, the car is losing the ability to accurately place it in 3D space.
I own a new 2021 M3LR same issue. Three times in one day passing semis on a two lane road. The third time scared me so bad I won’t use cruise or autopilot. The car went from 60-nearly zero in seconds. Had a car been behind me there would have been a bad accident.
 
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I own a new 2021 M3LR same issue. Three times in one day passing semis on a two lane road. The third time scared me so bad I won’t use cruise or autopilot. The car went from 60-nearly zero in seconds. Had a car been behind me there would have been a bad accident.
Phantom braking changes for me every software release. My wife hates the braking - scares her all the time (although it's usually just hard braking, NOT emergency braking). I was hoping the beta FSD would be better but it seems to just change when it does phantom braking. There is an option to turn off automatic emergency braking, I think it's under autopilot?

The new beta FSD does seem to finally handle visible stops signs on side streets so things seem to slowly be getting better...
 
Similar experience last weekend. I was driving in the right lane of a 4-lane highway. I had autopilot set at the speed limit (70 mph) with the car ahead of me at a safe distance, and a semi-truck behind me (also at a safe distance). A car passed us in the passing lane and my 2022 M3LR abruptly slowed (felt like hard braking to me). I glanced up at the rear view mirror and saw the semi behind me veering back and forth onto the shoulder and back into the lane trying to slow down so as not to hit me (looked like it was going to jackknife). I hit the accelerator and gave him enough room to recover. I’m lucky that the semi didn’t crunch into me (or over me), and that it didn’t jackknife off the road.

I’ve had it do this (“phantom brake”), twice since then. Once in daylight for no apparent reason. And this evening I was the only car heading south on a 4-lane road, when a car in the northbound lane passed and my car abruptly slowed. The only thing I can think of is that the system somehow misinterpreted the headlights (or reflections of the headlights on the road) from the other car as being in my lane.

So I’ve decided not to use cruise control or autopilot until a software update or something else is done to rectify this dangerous issue.
 
I understand phantom braking significantly constrains the vehicle’s cruise control functionality. That’s frustrating (my 2016 Civic has great adaptive cruise control). But I’m much more concerned about what this issue means for the vehicle’s broader active safety features beyond cruise control (emergency braking, collision warning, etc.). Are current owners experiencing issues with their active safety features?

It seems the IIHS is currently testing the 2021 Model Y without radar. Hopefully we’ll learn more soon.
In just 143 miles of driving since new, my “2022” Model 3 LR has phantom-braked 5 times. The NHTSA (US) has received many complaints, including mine. I am hopeful Tesla can correct the issue with a software update.
 
Similar experience last weekend. I was driving in the right lane of a 4-lane highway. I had autopilot set at the speed limit (70 mph) with the car ahead of me at a safe distance, and a semi-truck behind me (also at a safe distance). A car passed us in the passing lane and my 2022 M3LR abruptly slowed (felt like hard braking to me). I glanced up at the rear view mirror and saw the semi behind me veering back and forth onto the shoulder and back into the lane trying to slow down so as not to hit me (looked like it was going to jackknife). I hit the accelerator and gave him enough room to recover. I’m lucky that the semi didn’t crunch into me (or over me), and that it didn’t jackknife off the road.

I’ve had it do this (“phantom brake”), twice since then. Once in daylight for no apparent reason. And this evening I was the only car heading south on a 4-lane road, when a car in the northbound lane passed and my car abruptly slowed. The only thing I can think of is that the system somehow misinterpreted the headlights (or reflections of the headlights on the road) from the other car as being in my lane.

So I’ve decided not to use cruise control or autopilot until a software update or something else is done to rectify this dangerous issue.
Hell may freeze over before they fix the problem, it has been going on for quite awhile.
 
I own a new 2021 M3LR same issue. Three times in one day passing semis on a two lane road. The third time scared me so bad I won’t use cruise or autopilot. The car went from 60-nearly zero in seconds. Had a car been behind me there would have been a bad accident.
Same experience in my 21 vision only M-Y. Family road trip and car emergency braked when it saw semi in oncoming lane. iPad, phones, food and drinks went everywhere. If a car was behind us it would have been bad accident. Tesla has enormous liabilities rolling around out there with vision only Y and 3s. They need to fix it, like NOW!
 
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