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PSA: CAREFUL--Autopilot sudden braking

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I took delivery of my 3 on Saturday and experienced this behavior over the weekend 2-3 times. I’m in the Bay Area too so you’d think they’d have a lot of data to tune the algorithm over here.

You guys should measure the g-forces with an acceleration meter. There are apps for your phone that are extremely accurate, though I can’t recommend specific ones. @SleeperService used one to instrument (extremely accurately) his acceleration runs.

This has been done before, but definitely curious to see what is the max g-force that people experience. I’ve experienced some mild unexpected braking events which annoy my wife (not a high bar! ;) ), but nothing that would concern me if I were alone - maybe 0.1g? I haven’t instrumented it, since it seemed to be extremely mild.
 
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This happens to me so often I do not use it anymore, cause I don’t trust it enough. I try to show my wife how it works and this scared the crap out of her! It breaks for no reason and I just take it off autopilot! Tesla needs to fix this somehow cause this can cause accidents while traveling at high speeds.

It happens to me occasionally, but much less forcefully than it did a few firmware versions ago. AP/EAP are beta features, Level 2, and just as I keep my hands on the wheel, I have my foot near the pedals. Touching the accelerator pedal will override any braking event. And of course touching the brake will cancel AP/EAP. Phantom braking is a problem, but for me I still find EAP better than driving myself, when circumstances permit.
 
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I used to get it frequently, but I think it's been over 6 months since it last happened to me. The only time it slows down on me now is when I'm using NoA and a lane merges, so it slows down to let a car merge in. But it's not a sudden braking event either but rather a gentle slowdown.

Admittedly, most of the time I'm using Autopilot is when there's traffic in front of me. Seems to be a lot less likely to happen if there's a car the system can track through whatever it thinks is a block on the highway. But if I do start going near overpasses and there's no traffic in front, I still put my foot near the accelerator pedal just to be ready for it.
 
Same, and I wrote about it on the 2019.24.4 thread. I can't use AP anymore with this bug because it's constant for me. Anytime I encounter an underpass it slams the breaks and doesn't let up. I've also noticed that any type of shadows from above will make AP behave in the same manner. I started using the cruise control whatever it's called now, and it does the same breaking patterns, but not as bad. I have stopped using both features until another update is rolled out.
 
At least I’m not the only one. I have a black one and I’m starting to see halos on my car. Seems like paint issue with clear coat. Sheesh to many small issues but car drives like a champ!

Yes. I have them, too. They need to be polished out. You’ll notice under a light that there’s probably a paint imperfection like a nib right in the center of the halo - the halo is the result of wet sanding and then not polishing it out. It’s annoying, but pretty normal, unfortunately.
 
Nope! HW3 and it happens for me, too.

HW3 may fix that, when Tesla will start utilizing the hardware to its full potential.

However, I think some of the issues are not related to the processing power. I can understand why Tesla may be *slow* in stopping before another object (car) *when it is present* (it makes sense), but when nothing is here, what is exactly Tesla slow to react to? Some fantom objects (false positives) which are not actually here? Maybe higher processing power will help reduce that, but and this is very IMHO the whole thing about "dancing cars" is at least a partial illustration that maybe Tesla sensor suite is not absolutely optimal, at least not under all conditions. So obviously car can "filter out" this somehow, but I would not bet that HW3.0 is all which is required to really fix that. I think at some point Tesla will need to improve their sensor suite. Chances are that for a really good FSD (not per Tesla, but per regular people who never seen Tesla Autopilot before) both HW3 and some sensor suite updates will be required.
 
I also notice when I’m on regular streets stopped at a light the radar shows car twirling and sliding looks all glitchy, is that normal or is it just my car.

I call it "dancing cars." At first they just twitched side to side, bumping into each other. But now they do that and also twirl. Also, when I pull out of my garage the car sees a non-existent truck where the garage wall is. The display seems to have gotten worse at showing what's around me. I don't rely on the display for surrounding traffic, so it's just kind of funny.
 
I call it "dancing cars." At first they just twitched side to side, bumping into each other. But now they do that and also twirl. Also, when I pull out of my garage the car sees a non-existent truck where the garage wall is. The display seems to have gotten worse at showing what's around me. I don't rely on the display for surrounding traffic, so it's just kind of funny.
I noticed on 24.4 that they completely stopped dancing for me. I usually do a hard powerdown after firmware updates though, not sure if that affects it.
 
If you buy FSD option is there a way to just use adaptive cruise control without the other auto-driving stuff? I want to get the FSD just so I have it when (if) they ever get it working, but I don't want to deal with bugs like this so I'd rather just use regular adaptive cruise control until they get the bugs worked out.