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False Positive Automatic Emergency Braking at 80mph

While driving 80mph on a highway and my lane was clear of traffic in front of me. However, traffic visualization displayed a small sedan in front of my car, adjacent to the semi I was passing. As I approached closer to the false car, automatic emergency braking suddenly engaged and slowed me down to a near complete stop. There was a shiny reflection from the semi that was projecting into my lane, right at the spot where the false car was displayed. I've included a video of the incident below. Is there a way to submit this video and data to Tesla to help prevent this from happening in the future?

I have another very similar video of me passing a semi with an even brighter reflection projecting into the lane in front of me, and automatic emergency braking was not engaged. Video proof can be shared on request. What was special about this false positive braking incident (much more severe and scary than phantom braking)? Can I do anything to disengage false automatic braking while its happening? I don't want to disable it in settings because it has worked great in actual cases besides this.


 
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S4WRXTTCS

Well-Known Member
May 3, 2015
6,821
8,328
Snohomish, WA
You can but at that point you have already given your passengers a heart attack and they won't want you using cruise control ever again.

As I understand it this wasn't phantom braking of cruise control, but full on activation of AEB which can happen without adaptive cruise control active.

The OP may have simply need to change his underwear hence the pull over.
 
Aren't you supposed to be able to override automatic emergency braking with the throttle?
Automatic Emergency Braking does not apply the brakes, or stops applying the brakes, when:

  • You turn the steering wheel sharply.
  • You press and release the brake pedal while Automatic Emergency Braking is applying the brakes.
  • You accelerate hard while Automatic Emergency Braking is applying the brakes.
  • The vehicle, motorcycle, bicycle, or pedestrian is no longer detected ahead.
This paragraph confused me in the owners manual, it sounds like all the 4 items listed will not override AEB while its engaged? This is why I didnt attempt any of these 4 things because this paragraph makes it seems like these 4 things wont stop AEB.
 

S4WRXTTCS

Well-Known Member
May 3, 2015
6,821
8,328
Snohomish, WA
Automatic Emergency Braking does not apply the brakes, or stops applying the brakes, when:

  • You turn the steering wheel sharply.
  • You press and release the brake pedal while Automatic Emergency Braking is applying the brakes.
  • You accelerate hard while Automatic Emergency Braking is applying the brakes.
  • The vehicle, motorcycle, bicycle, or pedestrian is no longer detected ahead.
This paragraph confused me in the owners manual, it sounds like all the 4 items listed will not override AEB while its engaged? This is why I didnt attempt any of these 4 things because this paragraph makes it seems like these 4 things wont stop AEB.

No, all four items will override AEB.

More importantly hitting the accelerator will override Phantom braking.

I've only experienced AEB once in my life, and that was with my Jeep Wrangler. It was so intense, and so fast that there wasn't time to do anything. Luckily it happened when I was going down a ramp into a parking lot. The car sensed the concrete it thought I was going to hit, but was never going to hit as I was going under it. The vehicle slammed the brakes and I don't think I could have prevented it even if I tried.

All the Phantom braking I've experienced in my Tesla so far has been mild to moderate phantom braking with either TACC/AP so those are always recoverable with the throttle.
 
I got one today. For no valid reason on a two lane road. Just normal traffic driving the other way in their lane. MYP slammed on brakes as hard as possible with alarms going off. 40mph to zero in about 1 second. No chance to even react in time. Extremely close to being smashed by the big diesel truck skidding behind us blaring his horn while I floored the car to barely get out of his way. This system full on emergency braking on false alarms is way more dangerous than not having it. It terrifies everyone in the car.
 
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S4WRXTTCS

Well-Known Member
May 3, 2015
6,821
8,328
Snohomish, WA
I got one today. For no valid reason on a two lane road. Just normal traffic driving the other way in their lane. MYP slammed on brakes as hard as possible with alarms going off. 40mph to zero in about 1 second. No chance to even react in time. Extremely close to being smashed by the big diesel truck skidding behind us blaring his horn while I floored the car to barely get out of his way. This system full on emergency braking on false alarms is way more dangerous than not having it. It terrifies everyone in the car.
We're you in TACC/AP when it happened?

AEB can happen whether you're on AP/TACC or while you're driving, but I'm curious regardless.
 

S4WRXTTCS

Well-Known Member
May 3, 2015
6,821
8,328
Snohomish, WA
AEB only activates when on cruise CC/AP/EAP/FSD. It never activates when driving manually.
AEB can activate at anytime as that's the entire point of automatic emergency braking.

On this link scroll down to the Automatic Emergency braking.

 
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While you were being slammed forwards did you happen to glance at the screen to see if the "Emergency braking in progress" was on?

I'm also curious if it stores this notification in the notification history.
I have only had the car for a few weeks. I did not even know to look for that until I read these posts here. It happened so fast that I was more concerned with having an infant in the car and getting creamed by the large truck behind us at the time. All I know is there was an ultra-loud alarm going off when it happened. I have had phantom braking incidents with controllable braking slowdowns. This was NOT that. This was slamming on the brakes as hard as possible (tires barking) to a full stop in the middle of the road with zero warning and an alarm blaring at us so loud it scared the hell out of everyone, while the other car drove by in the other lane normally, nowhere near the center line, minding his own business.

I looked at notifications (Cruise control will not brake, accelerator is pressed) - matches the time of the incident. This is the only message. Maybe from me flooring it to avoid getting hit when the car stopped with TACC on? I can't imagine what would happen if the car did this on the freeway this violently in traffic.
 
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S4WRXTTCS

Well-Known Member
May 3, 2015
6,821
8,328
Snohomish, WA
I have only had the car for a few weeks. I did not even know to look for that until I read these posts here. It happened so fast that I was more concerned with having an infant in the car and getting creamed by the large truck behind us at the time. All I know is there was an ultra-loud alarm going off when it happened. I have had phantom braking incidents with controllable braking slowdowns. This was NOT that. This was slamming on the brakes as hard as possible (tires barking) to a full stop in the middle of the road with zero warning and an alarm blaring at us so loud it scared the hell out of everyone, while the other car drove by in the other lane normally, nowhere near the center line, minding his own business.

I looked at notifications (Cruise control will not brake, accelerator is pressed) - matches the time of the incident. This is the only message. Maybe from me flooring it to avoid getting hit when the car stopped with TACC on? I can't imagine what would happen if the car did this on the freeway this violently in traffic.
What I find really annoying about Tesla is they don't show all the notifications in the notification history.

Instead they seem to show the silly ones like cruise control will not brake. That doesn't tell an owner anything they don't already know.
 
MYLR vision only, just completed 2000km road trip. Starting out I knew the AP was going to be off most of the trip because of the terrible way it disengages, but I did not foresee that I would have to turn off the TACC for every oncoming car.

Had multiple hard brakes with loud beeping scaring everyone in the car for no reason 😟
 

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