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PSA: CAREFUL--Autopilot sudden braking

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Happened to me yesterday on 3rd day of ownership. Shadow from overpass caused it on commute home from work when traveling around 60 mph. Car following was not tailgating. Wide spacing in front of me. I am guessing in tighter traffic EAP would have followed a car in front and ignored the shadow. Definitely a reminder to pay attention and be ready to take control.
 
Didn’t see this thread and created another one.
I have V8.1 (2018.18.3 04dfd3c)

Yesterday morning, on the way to work, my car just slammed on a brake while on autopilot TACC w auto steer. It was a sunny morning and a 18 wheeler was on my right with a big shadow to my side of freeway. I think autopilot engaged brake because of shadow of the truck. Similar situation with freeway overpass shadows. It’s all seems random. Sometimes it doesn’t react and drive through and some days, it brakes. Luckily, so far, cars behind me slowed down quickly. I am sure they were going WTF, f$%!# Tesla driver.

This bug needs to be fixed before I get rear ended by a big 18 wheeler.
 
Didn’t see this thread and created another one.
I have V8.1 (2018.18.3 04dfd3c)

Yesterday morning, on the way to work, my car just slammed on a brake while on autopilot TACC w auto steer. It was a sunny morning and a 18 wheeler was on my right with a big shadow to my side of freeway. I think autopilot engaged brake because of shadow of the truck. Similar situation with freeway overpass shadows. It’s all seems random. Sometimes it doesn’t react and drive through and some days, it brakes. Luckily, so far, cars behind me slowed down quickly. I am sure they were going WTF, f$%!# Tesla driver.

This bug needs to be fixed before I get rear ended by a big 18 wheeler.
Report the bug through the Tesla account. The more people they here from, the faster they may take action. This is really dangerous if it does not get fixed.
 
I still think there should be a super quick, one-gesture 'wtf' button/tap/etc that flags the moment as 'I think autopilot messed up'. I hope they do it automatically for large actuation deltas, but many more people experience this than actually bothered to submit a bug. Also, I don't think it is smart to equate AI training to a bug - it should err on the side of being over-sensitive (lots of false positives) rather than over-specific (lots of missed real reports)
 
I feel like this is a matter of tuning. It is going to be a while before it's "perfect" (if that is even possible). As long as idiots do not watch out the front window when AP is activated and run into large objects, Tesla is going to be paranoid about running into things and be cautious in this regard.

Personally, I'd prefer less aggressive emergency braking - I do pay attention and will spot something that is in front of me. The car auto-slowing comes as a surprise.

I haven't tried setting the option to "less aggressive" (or even off) in the driver assistance settings page.
 
For the one week I had my M3 (it's in the shop now), I never experienced sudden braking. I've used AP about 10 times (majority on 18.3) and the only issue I encountered (twice) was where I'm on the freeway going through an underpass and the M3 almost drifts off the lane. It hugs the right side while under the same bridge, which scared the crap out of me since I thought I might clip the adjacent vehicle. The first time I took control back but the second time I let AP do its thing and it stayed within the lane. Both were around 6:30AM on the way to work.

I wasn't aware of this problem so glad I came across this thread. Hope it's addressed soon!
 
I feel like this is a matter of tuning. It is going to be a while before it's "perfect" (if that is even possible). As long as idiots do not watch out the front window when AP is activated and run into large objects, Tesla is going to be paranoid about running into things and be cautious in this regard.

Personally, I'd prefer less aggressive emergency braking - I do pay attention and will spot something that is in front of me. The car auto-slowing comes as a surprise.

I haven't tried setting the option to "less aggressive" (or even off) in the driver assistance settings page.
I slightly disagree. If this was tuning, it would have been more prevalent much earlier on. I have had my M3 since January and used autopilot pretty extensively prior to receiving 14.13 update and never had the issue. Once I got the 14.13 update, I started seeing this issue--enough to report it and have people corroborate. I am not saying there were not isolated events prior to the 14.13 update, but to have it become more widespread would point to a bug or overly sensitive adjustment.
 
I slightly disagree. If this was tuning, it would have been more prevalent much earlier on. I have had my M3 since January and used autopilot pretty extensively prior to receiving 14.13 update and never had the issue. Once I got the 14.13 update, I started seeing this issue--enough to report it and have people corroborate. I am not saying there were not isolated events prior to the 14.13 update, but to have it become more widespread would point to a bug or overly sensitive adjustment.
Perhaps your right on the 3. But the S has gone back and forth over the years. Depending on how they weight the radar, camera, and the maps.
 
Autonomous ops are hard. There are so many edge cases it's difficult to see how they can all be safely solved any time soon, and perhaps not within the reasonable lifetime of a new car deployed today. I think Uber has (finally) come to understand that.
Robin
 
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I have experienced this about 3 times over the last ~800 miles of EAP. It's surprising and undesirable for sure. If you're paying attention, it's not the end of the world to over-ride with the accelerator. I do think it poses a rear-end collision, particularly if someone is close or tailgating you. I hope Tesla can find the cause of this behavior and swat it quickly. I'm not overly frightened by this and will continue to use EAP for now.

Can someone who remembers, please remind us how to use the voice command in the car to report this issue right after it happens?
 
I have experienced this about 3 times over the last ~800 miles of EAP. It's surprising and undesirable for sure. If you're paying attention, it's not the end of the world to over-ride with the accelerator. I do think it poses a rear-end collision, particularly if someone is close or tailgating you. I hope Tesla can find the cause of this behavior and swat it quickly. I'm not overly frightened by this and will continue to use EAP for now.

Can someone who remembers, please remind us how to use the voice command in the car to report this issue right after it happens?

This also happened to me twice in quick succession while using TACC only (Not AP) on the 110-N freeway South of downtown LA in the Express lanes. No leading or trailing traffic, no visible overpass, and I don't recall seeing any shadows either. Speed was about 70mph.

The reason I bolded the above is because when the sudden deceleration happened, the obvious thing was to accelerate, and I did just that, for maybe < 2 seconds. The instant I took my foot off the accelerator, the car immediately hard braked again. I'm like WTF? Then instead of simply reacting again (i.e. hit the accelerator) I had to stop and think about how to regain control of the car. So then I had to brake to disengage the TACC, which is exactly the opposite of what you would normally do when the car spontaneously hard brakes for no reason. Was a bit shaken by this. Almost called the local service center to ask them to "pull the logs", but was busy and the entire episode got overcome by events. It has not happened again since then, though my TACC use has been less, and Mrs. Toe had the car for 10 days and she doesn't use the TACC or AP.

I would also be curious if there is indeed a voice command to get this info back to Tesla automatically. Maybe the car automatically sends this info back when it automatically does a hard brake? It could certainly flag the event, and send the data later. I just don't know whether it does that or not. Anybody know? The manual certainly doesn't get into that level of detail.

RT
 
Just heard back via email (see below). hopefully speak to them today. I haven’t use autopilot in a while so I will not be helpful in diagnosing the problem since it won’t show in the logs. Anybody that has had it happen recently should write Tesla via your account so they can see the logs

Thank you for writing in! I have not heard about this issue occurring particularly after this firmware update. Sometimes, the vehicle decelerates when it detects an overpass. I am not sure if that is the case but I reached out to our Vehicle Support team and they will call you to investigate further. They have expertise and better tools when it comes to troubleshooting. Please feel free to reach out to me if you do not receive any call from them today. Have a great day!
Best Regards,

Executive Care
 
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