Autopilot failing and causing hard braking

Autopilot failing and causing hard braking

2018 with upgraded Autopilot (camera's etc). Often I will have cruise control and autopilot on traveling 75-80mph. Lately when a car enters the highway into its own lane to my right, my car hits the breaks as if there is a car in front of me that has slowed or stopped. it is a hard break, but not a screech to standstill. i have to tap brake to get out of autopilot and take back over. Also, often when i am at a stop light and the dashboard is showing the cars around me they are all freaking out and switching places sizes even turning sideways! not sure what this is all about but i hate taking to service as Costa Mesa must have 100 cars in for service at any one time...and no loaners!

quann415 | 10 juin 2019

I have the same problem with the cars around me freaking out..twisting and turning, etc. Autopilot in my 2017 100D has the's brakes hard for no reason sometimes and is very slow to respond to merging traffic with regard to speeds, etc. It is so annoying that I just simply take over. Feels like half baked.

rdalcanto | 10 juin 2019

I have multiple Teslas and they all brake for no reason on Autopilot. I cover the accelerator with my foot at all times so I can over ride it. I hope it gets better with new software updates.

SoCal Buzz | 10 juin 2019

Firmware version anyone?? 2019.20.1 is smoother with negligible phantom braking.

bp | 11 juin 2019

Even when just running under TACC (without AutoSteer/NOAP engaged), the recent software will periodically slow on highways sometimes for no obvious reason.

It appears the software is being overly cautious, based on the data it is receiving - and over time as the software training continues, we should see fewer of these instances.

Until then, I have to be ready not only to monitor lane changes and lane keeping, but maintaining speed.

Wish there was a way to turn off the automatic speed adjustment until it is working better...

redacted | 11 juin 2019

Them's the breaks, but the car is using the brakes. Please spell it accordingly.

My gripe with braking is that the car overreacts to cars crossing the lane or turning far ahead. It's like a timid drivers' education student.

As @quann415 so delicately hints, you don't need to take the car out of autopilot to use the accelerator pedal. Just use exercise fine control so you don't snap your neck and ease off gently in case autopilot is still skittish.

EVRider | 11 juin 2019

Sometimes when there’s a car in the adjacent lane and ahead of me, my car will incorrectly see the other car slightly crossing the lane marker (the dash display shows this), and my car will slow down unnecessarily.

packpike | 11 juin 2019

@redacted - that's when I see the worst instance of this problem. It's quite annoying when I know that the car that's turning in front of me up ahead will be long gone before I get there, but my car slams on brakes and scares everyone in the car.

hankp | 11 juin 2019

cofefe @redacted

My first tesla in 2015 did not have this problem and had only the basic autopilot, not the cameras, etc. it worked much better than this one!

EVRider | 11 juin 2019

@hankp: My previous 2016 Model S with AP1 had the same issue I described above. I've never had either car "slam on the brakes" -- they just slowed down.

harry pippic | 11 juin 2019

Many TESLA owners just don't get it. The AUTOPILOT feature is only in ""BETA MODE"" drivers using this feature must ALWAYS beware of this and you must NEVER release full control to the vehicle.

Autopilot is in BETA Mode and is only a driver's assist, and NEVER forget that. !

Hammonddave | 12 juin 2019

Agreed... this is not a perfected system. It’s in Beta... that says it all. I just completed a trip from Long Beach to Denver. Used NAP 90% of the time. But my eyes were on the road and hands on the wheel 100% of the time.

bp | 13 juin 2019

Treat the AP software as a student driver - who you would want to be more conservative - slowing down more than necessary to ensure safe driving.

Unlike student drivers, the AP software should be rapidly improving using the huge amount of data collected through fleet learning from all Tesla vehicles built since late 2016 - so it should take months for the AP software to operate better, vs. years for student drivers.

impala1ss | 15 juin 2019

Hammonddave | June 12, 2019
Agreed... this is not a perfected system. It’s in Beta... that says it all. I just completed a trip from Long Beach to Denver. Used NAP 90% of the time. But my eyes were on the road and hands on the wheel 100% of the time.

What does your post have to do with hard braking? It's happened to me several times and is quite a thrill for the driver behind me. I have my hands on the wheel at all times and eyes on the road at all times.

dir | 15 juin 2019

I find this random hard braking dangerous.
If there is no one directly in front of me on the highway, and there IS someone directly behind me, and TACC hits the brakes for no obvious reason - it shows up as me brake-checking the car behind me.
That is a ticket-able offense, and eventually will cause an accident that will be my fault.
I have captured a couple of these instances on video, and will be going to a Tesla Service Center to get it resolved.
AND its still happening on 2019.20.1 .

Johnmmurphy | 16 juin 2019

I have the same problem with unexpected braking while traveling on the highway. It is an accident waiting to happen. Other vehicle manufacturers have offered dynamic cruise control and it works just fine.
I am surprised that Tesla hasn't figured this out.
Is there a fix available at the present time?

rsrivast | 17 juin 2019

I have stopped using AP/ NAP when driving on HOV lane with slow /stopped traffic in the adjacent lane. It is too risky due to phantom braking symptoms. NAP is also distracting in heavy traffic with frequent lane changes at unsafe locations - have to keep cancelling it. It also sets the indicator for too long which confuses other drivers. I guess it first indicates and then tries to figure out the lane change, should be the other way round. A safe lane change should complete in ~5sec. Also the Radars / Camera need to scan longer than 150' to get a holistic view of the surrounding traffic. Makes me wonder if Tesla's FSD is still on track by end of 2019 (as per Elon M). The last 10% of the work takes 90% of the time in any neural net project.

david.kennedy | 17 juin 2019

Having the same issue here on the 2019 model S.

Haggy | 17 juin 2019

This is the way that Autopilot works as documented. The latest version of the manual warns that this may happen and lists some circumstances under which it will happen.

Ideally, Tesla will get all of these under control, but I don't think that the braking is more severe than it would have been had a car actually moved in front, so it's not something that the driver behind shouldn't be prepared for. It might be slightly jarring if there's nothing in front causing it, but it might appear normal to the driver behind, who would expect cars to slow down based on traffic ahead.

As for the nearby cars that are dancing, it's not something specific to your car.

Pungoteague_Dave | 17 juin 2019

That's not a failure, it is a feature. You are participating in a grand deep learning process, with your life as a potential contribution. Any fanboi will tell you it is your responsibility to support your car (and Tesla) while it is still a child learning how to drive. Carry on.

Yodrak. | 18 juin 2019

My experience is that phantom braking is a TACC issue. It happens even when not using AP or NAP.

diamonds2 | 18 juin 2019

@Yodrak: My experience also.

sr.smr | 18 juin 2019

david.kennedy, does your car have HW3? If it does, it would prove the software is still not written to take advantage of the better processor. Does the car also make the pumping brake noise when slowing down? My 2017 HW2 always suffered from the described symptoms plus the pumping brake noise.

martinfg2 | 19 juin 2019

In response to the OP, I had an "interesting" experience where Autopilot became unavailable after returning to the parked car after a few hours being parked in a garage. I don't recall if I had sentry mode on, but it's possible. After driving for a couple hours without Autopilot or TACC available, I reached my destination, parked, then rebooted using the thumbwheels (soft reboot). Autopilot/TACC became available, but I noticed cars around me were "dancing" like they used to a year ago with older software. I then did a "hard" reboot including holding the brake and the thumbwheels for ~ 1 minute until after the T reappeared on the rebooting console. This seemed to cure the issues, and the car was back to normal.

Bottom line: Try a hard reboot of the center console to see if the dancing cars calm down - it might also help with phantom braking.

late 2016 Model S, EAP, HW2

sr.smr | 19 juin 2019

Unfortunately reboot did not cure the dancing cars for me. Curious - are the problems discussed in this thread also shared with Model 3 cars?

revrev4ruach | 19 juin 2019

I have issues. This is one of them. Thanks to the OP, I know I'm not alone.

dhan.hapuarachchi | 20 juin 2019

I have experienced this problem since updating to the latest software. I have also had an instance where the OS froze and the system rebooted while I was driving on the motorway @ 70mph. The good thing is that the car still allowed me to control the steering and acceleration/braking. I hope these issues are sorted by an update.

mcdonalk | 20 juin 2019

Interestingly, I used to experience this but haven't in the past several months. Possible explanations include, but are not limited to:

a) I use Navigate on Autopilot much more now
b) a SW update resulted in the improvement
c) my car "learned" something.

trivedi.niket | 24 juillet 2019

Experienced same problem here while Driving in UAE highways. 6 times in last 1 month twice yesterday.. in my new Car, just a month old.

johncrab | 24 juillet 2019

Back in 2014 I got pissed at Tesla when they added the first gen AP hardware just 23 days after my car was delivered. They knew they were going to do this and said nothing to me (the start of a pattern as it turned out). Since then I have driven various iterations of the AP system and I have to say, I'm not impressed, don't like it, would not use it as I find it the ultimate distraction and would not want to pay for it. It seems I dodged a bullet and got the car that was the best fit for me. For those who did walk into this with their eyes open, Tesla owes them far better performance, response and human treatment. I see this as a fad (many will disagree) which will go the way of the Sony L-Cassette, the C-band satellite dish, the fridge with a touchscreen computer in the door and the Apple Newton. Ideas that just never worked out as intended.

EVRider | 25 juillet 2019

@johncrab: Sounds like you’re still pissed about not getting AP. Get over it. :-)

Daisy the Road ... | 25 juillet 2019

Right ... because no one is using satellite TV, or a smartphone.
I'd hazard a guess that 1/4 of the miles on our MS have been on autopilot.