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Ghost Braking Danger on Cruise Control

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Twice today my model 3 came to a hault when using cruise control on the highway. The second time everything in my car was thrown into the front seat/windshield as i was going 80mph and I took over but was at 30mph by then as it happened so fast .. WTH is going on as I could have been killed and/or killed others.

It's not that my cameras are dirty or other excuses, something is really wrong here.
 
Last 3 trips for me and totally repeatable. Car does not know what the speed limit is on part of the new motorway, automatically switches from 70 to 45 and starts to break. Replicated it many times now and also ready for it. I think road sign reading is much needed here. Close call on the rear the first time to happened, I had to floor the accelerator.
 
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There's a huge difference between "drops to a lower speed limit" and "comes to a complete stop on the highway"

The first is a database error.

The second is a dangerously defective car.

BTW slowing from 80 to 30 should take at least 4 full seconds, that's a LOT of time...way more than it should take for a human to notice and react and get back on the gas pedal....1.5-2.3 seconds is usually "normal" human reaction time used by accident reconstruction folks.
 
Twice today my model 3 came to a hault when using cruise control on the highway. The second time everything in my car was thrown into the front seat/windshield as i was going 80mph and I took over but was at 30mph by then as it happened so fast .. WTH is going on as I could have been killed and/or killed others.

It's not that my cameras are dirty or other excuses, something is really wrong here.

Please report it using the bug report function.
 
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Last 3 trips for me and totally repeatable. Car does not know what the speed limit is on part of the new motorway, automatically switches from 70 to 45 and starts to break. Replicated it many times now and also ready for it. I think road sign reading is much needed here. Close call on the rear the first time to happened, I had to floor the accelerator.

The only phantom breaking for me are when the speed limit changes or it thinks the speed limit is something it's not.
 
Twice today my model 3 came to a hault when using cruise control on the highway. The second time everything in my car was thrown into the front seat/windshield as i was going 80mph and I took over but was at 30mph by then as it happened so fast .. WTH is going on as I could have been killed and/or killed others.

It's not that my cameras are dirty or other excuses, something is really wrong here.
My M3 is almost 2 yrs old and suffered from ghost braking occasionally (nothing as severe as you report). Factory reviewed my data but could not recommend a fix. Got HW3 upgrade and frequency of ghost braking increased, accompanied by ‘side door camera is blocked’ notification. Mobile service replaced the camera, and all has been well since. Detection of merging traffic from right also improved.
 
Huh? My dad's 2014 Mercedes S Class has TACC and it NEVER phantom brakes. So it's not "absolutely new tech" and it's not a given that all TACC systems are as bad as Teslas.

Standard TACC on your Dads Mercedes is absolutely not even in the same world as the tech going on in the Tesla. ....
I’m not an expert in this area, but I do know Tesla uses cameras, radar, and sensors, coupled with software to interpret those results to create self driving.

My old BMW Had TACC as well, and the tech that ran that, was not even close to Tesla.

Full self driving is definitely new tech.
 
Standard TACC on your Dads Mercedes is absolutely not even in the same world as the tech going on in the Tesla. ....
I’m not an expert in this area, but I do know Tesla uses cameras, radar, and sensors, coupled with software to interpret those results to create self driving.

My old BMW Had TACC as well, and the tech that ran that, was not even close to Tesla.

Full self driving is definitely new tech.

It's TACC vs TACC. Mercedes got TACC right in 2014, Tesla, not so much in 2020.
 
BTW slowing from 80 to 30 should take at least 4 full seconds, that's a LOT of time...way more than it should take for a human to notice and react and get back on the gas pedal....1.5-2.3 seconds is usually "normal" human reaction time used by accident reconstruction folks.

Agreed, even with bad phantom braking incidents i think i've maybe lost 10-20 mph before realizing and taking over. Still can be fairly sudden and unsafe though.
 
It's TACC vs TACC. Mercedes got TACC right in 2014, Tesla, not so much in 2020.

Same name, but worlds apart on how the computer carries it out, and that matters if you’re assuming (which it appears you are) it’s just old tech.

So does Mercedes use Cameras to feed information into a neural network to have the computers in the car make decisions. ?

Saying it’s TACC vs TACC implying that Tesla should get this right, because Mercedes has been doing it right for years, is like comparing an old rotary land line phone to a new cell phone.
They are both called phones, (Phone vs Phone), so why do new cell phones sometimes lose signals, when the old rotary phones they used for decades never lost a signal.
Same name, (phone vs phone) but completely different tech, around how they work.

Tesla’s delivery system is extremely complex and new compared to how the old TACC systems worked. It will have bugs while this is perfected.
Trying to compare the two, like you did, might imply you don’t understand the differences, or maybe you do, and you’re just using it as another exaggeration to attack Tesla again.

Not sure if either assumption is right here....
 
Same name, but worlds apart on how the computer carries it out, and that matters if you’re assuming (which it appears you are) it’s just old tech.

So does Mercedes use Cameras to feed information into a neural network to have the computers in the car make decisions. ?

Saying it’s TACC vs TACC implying that Tesla should get this right, because Mercedes has been doing it right for years, is like comparing an old rotary land line phone to a new cell phone.
They are both called phones, (Phone vs Phone), so why do new cell phones sometimes lose signals, when the old rotary phones they used for decades never lost a signal.
Same name, (phone vs phone) but completely different tech, around how they work.

Tesla’s delivery system is extremely complex and new compared to how the old TACC systems worked. It will have bugs while this is perfected.
Trying to compare the two, like you did, might imply you don’t understand the differences, or maybe you do, and you’re just using it as another exaggeration to attack Tesla again.

Not sure if either assumption is right here....

how it works behind the curtain shouldnt be the liability of the driver, or trailing motorists...
 
The most common error I see now is a GPS/Maps issue where the car picks up the speed limit from a nearby road or has an incorrect entry for a section of road. Repeatable, so easy to be aware of on regular routes.

Yep exactly this seems to be the sole hick-up I witness now since the last 2 patches. We watched intently the last 2 passes as before it felt like it was an overhanging smart sign but it is in fact trailing roads under the motorway at this section. The road sign of 70 vanishes and is replaced with an autopilot limit of 45 which results in a stab at the breaks and regen automatically. Resumes to 70 about 15 seconds later but by then I have had to take immediate action to compensate. Apart from that Autopilot was flawless and even seems to be taking more action in reducing speed around some corners and approaches to more roundabouts.
 
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