Tesla braked hard when car crossed in front

[Geoff45]

So I was driving with cruise control on the Pacific Highway. Someone made a right hand turn across my path. It was quite safe. I wouldn’t even have braked driving an ICE car. However my m3 braked very hard and there was risk of a collision from the car behind me. Does this only happen with cruise control or would have happened without CC?
Ha anybody else experienced this?
Geoff

 

[AndyCharged]

Yes this happens to me. It can be very aggressive some times and can slow down very quickly to avoid a car in front even if it will exit the path shortly after.

This can happen in CC and Autopilot

 

[paulp]

So I was driving with cruise control on the Pacific Highway. Someone made a right hand turn across my path. It was quite safe. I wouldn’t even have braked driving an ICE car. However my m3 braked very hard and there was risk of a collision from the car behind me. Does this only happen with cruise control or would have happened without CC?
Ha anybody else experienced this?
Geoff

This only happens when the tesla cruise control or autopilot are engaged, and get used to it as it happens often. I no longer use it.

 

[Hairyman]

Yeah, it really hates traffic crossing in front of your path. It will do it, but not violently, even when the crossing traffic is more than 80m ahead. It seems some terrible buried memory of a widely publicised crash of a Model S t-boning a truck crossing a highway in the US.

 

[cafz]

The car doesn't know that the crossing vehicle won't just decide to stop dead.

(Really, you don't know that either - you're just playing the odds it won't.) You can override it with the accelerator, so if you see cross-traffic approaching you might want to hover your foot over the pedal.

 

[Lance From Jax]

So I was driving with cruise control on the Pacific Highway. Someone made a right hand turn across my path. It was quite safe. I wouldn’t even have braked driving an ICE car. However my m3 braked very hard and there was risk of a collision from the car behind me. Does this only happen with cruise control or would have happened without CC?
Ha anybody else experienced this?
Geoff

Out of curiosity, is the car braking with the actual brakes or is it slowing with the regen? I wonder this with the "phantom braking" as well. The regen can be quite strong.

 

[mjwojtukiewicz]

So I was driving with cruise control on the Pacific Highway. Someone made a right hand turn across my path. It was quite safe. I wouldn’t even have braked driving an ICE car. However my m3 braked very hard and there was risk of a collision from the car behind me. Does this only happen with cruise control or would have happened without CC?
Ha anybody else experienced this?
Geoff

It did it to me the other day and I was not using ANY automated driving. Actually that's the first time it happened, car was about 10 feet in front of me and I was using single pedal driving to have car come to a stop. This has NEVER happened and I wasn't even sure AEB even worked. It certainly doesn't work in the back as I've had over a dozen near misses with pedestrians or cars whizzing by as I was backing out of a parking space. The rear cameras are useless as they don't have the range to see anything coming

 

[mfcat]

I have the same issue with Cruise Control, breaking with car crossing path ahead. When I first bought the car (Y) 2 years ago, the "phantom breaking" was very bad, happening all the time. Software updates have improved it a lot, but there remain issues with camera blinded when driving into sun, clouds in bright sky ahead, cars crossing path, and mirages on hot road on sunny day. I would like to see a not-so-smart cruise control that just maintained speed (and a quick resume if I cancel it), but for now just be ready to take control if road conditions change.

 

[paulp]

Out of curiosity, is the car braking with the actual brakes or is it slowing with the regen? I wonder this with the "phantom braking" as well. The regen can be quite strong.

Phantom braking, when you experience it, is full application of the brakes with abs kicking in to precent lockup. It is nothing like regen braking

 

[positiv]

Yes I have the same issue. The car will
violently brake when another vehicle crosses perpendicularly in front, even after the offending vehicle has passed. It’s a bit of a nightmare.

Luckily the force of the braking application will throw your foot into the accelerator and terminate the aberrant braking. But it’s a hell of a ride for your passengers when this occurs.

 

[dcfas]

Same. I have learned to hover my foot over the accelerator, rather than the brake. Even worse is when it breaks when there is an overpass. First time that happened to me I thought the car was breaking down. It was a shocker.

Another issue is the nag when in AP to take hold of the steering wheel, even though my hand(s) is on it. For that I have learned to click up one or down one on the volume knob.

 

[Teetoogrn]

Yes, my S does it too when using cruise or autopilot. I sometimes try to turn it off if I see the situation developing. Everyone has a driving style. Just think of it as your car’s style is like your grandmother’s…”You can never be too safe!”

 

[Jules22]

I had this happen a few times while going down the highway at 110, where there are crossings and a car up ahead crosses the highway, I wouldn't call it 'phantom braking' or even 'hard braking' though, it only slowed 5-10 km/h when left unchecked and then returned to speed as soon as the car cleared the highway. I think this is where the phantom braking gets overblown in that people use the term for any slow down which while they feel dramatic are not even using the brakes, it's just the sudden slow down using the regen braking.

I think as someone else mentioned, if you are driving AP/FSD with the foot ready on the accelerator and partciularly as you get used to how it reacts to certain situations, these can be virtually eliminated. I know in my case after the first couple of times, the subsequent ones only resulted in a drop of 2-3 km/h and were much more comfortable for the other occupants.

 

[Hairyman]

I had this happen a few times while going down the highway at 110, where there are crossings and a car up ahead crosses the highway, I wouldn't call it 'phantom braking' or even 'hard braking' though, it only slowed 5-10 km/h when left unchecked and then returned to speed as soon as the car cleared the highway. I think this is where the phantom braking gets overblown in that people use the term for any slow down which while they feel dramatic are not even using the brakes, it's just the sudden slow down using the regen braking.

I think as someone else mentioned, if you are driving AP/FSD with the foot ready on the accelerator and partciularly as you get used to how it reacts to certain situations, these can be virtually eliminated. I know in my case after the first couple of times, the subsequent ones only resulted in a drop of 2-3 km/h and were much more comfortable for the other occupants.

I get similar behaviour in my 3.

 

[OzVic]

Another issue is the nag when in AP to take hold of the steering wheel, even though my hand(s) is on it. For that I have learned to click up one or down one on the volume knob.

Unfortunately the volume knob trick doesn't work in Australian Tesla's

 

[paulp]

The car doesn't know that the crossing vehicle won't just decide to stop dead.

(Really, you don't know that either - you're just playing the odds it won't.) You can override it with the accelerator, so if you see cross-traffic approaching you might want to hover your foot over the pedal.

I suspect the car in front of me that did not brake is going to t’bone the car that is 150 metres away before I get to the scene

 

[Lance From Jax]

Phantom braking, when you experience it, is full application of the brakes with abs kicking in to precent lockup. It is nothing like regen braking

OK, thanks .Yeah I have never experienced this. I've been driving in construction, 26 miles a day, in the dark, in the sun, today in full rain in the dark with shiny reflections everywhere, super dark new asphalt with FSD on, a few times I needed to "take control" as FSD turned off. but no braking.

 

[paulp]

OK, thanks .Yeah I have never experienced this. I've been driving in construction, 26 miles a day, in the dark, in the sun, today in full rain in the dark with shiny reflections everywhere, super dark new asphalt with FSD on, a few times I needed to "take control" as FSD turned off. but no braking.

I have only experienced it on autopilot (several times). Here in australia we do not have the fsd that you have, so I cannot comment if it has the same failures.