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Possible to deactivate TACC and use "regular, dumb" cruise control? Phantom braking & unexpected slowdowns

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I just picked up a new model 3 a month ago. I drive 120 miles a day on a reverse commute that is 99% highway miles. I encounter very little traffic on my way to work.

Cruise control is something I can’t live without, but the Model 3 is making me reconsider that. I am fairly certain that without my intervention, CC and AP would have killed me by now, where just a normal “dumb” cruise control would have not been an issue.

The decision to prevent owners from disabling the “smart” cruise control is beyond dumb. It’s negligent, given the massive safety concerns with it currently.

The cruising performance would be spectacular if I could just disable all of the automated features. But right now, I am regretting my purchase big time and would not in good conscience recommend the brand to anyone that isn’t a complete tech nerd/early adopter/beta tester type. I also have major complaints about the purchase experience and service experience as well, and I typically have very high tolerance for the issues I have had, but these issues have been beyond the pale.
 
Isn't easier to just switch off TACC for passing? I do keep it on for some lane changes, but if I'm changing lanes to do a quick pass and merge back, I wouldn't really expect any car's ACC to handle that for me. That's advanced stuff, seems more FSD or at least EAP territory.
For me it's in the context of a multi-lane highway. If I'm cruising at 74 and come up on someone doing 70, I just want to leave the cruise at 74, smoothly move left, around the slower car, then smoothly move back to the right.

If I'm on a 2-lane road, I agree with you.

Yesterday, I took my 2012 Nissan LEAF to run several local errands. It is refreshing to drive that after mostly driving my Model 3 for awhile. Several things I really like about the LEAF and why I’ve kept it despite its miniscule and diminishing 35-mile range. Now that ambient temps are quite cool, the steering wheel heater is just wonderful, but the big plus is the dumb old cruise control. Simply and easily maintaining a speed set by me without having my right foot hover over the go pedal is so relaxing compared to the vagaries and self-indulgences of TACC. The ability to disengage and resume my set speed is yet another well-appreciated plus. Given that I’m forbidden to use TACC with she-who-must-be-obeyed or the German Shepherd who gives me WTF grimaces at every phantom braking event, and even alone I skip it most of the time, the chance to relax with a real cruise control has become one of life’s driving pleasures. After 3½ years in my Model 3, I know my next vehicle will have to have dumb cruise control if I can find it in any EV.
Ha! Love the characterizations of your SO and dog. I get the same reactions. I also love driving the Volvo XC40 I picked up to tide me over until my X Plaid is delivered. I just love the simplicity of dumb CC. The headlights are also outstanding compared to our S.
 
For me it's in the context of a multi-lane highway. If I'm cruising at 74 and come up on someone doing 70, I just want to leave the cruise at 74, smoothly move left, around the slower car, then smoothly move back to the right.
Ah, yeah, VO TACC accelerates much too slowly for that. It's too slow to accelerate in general, same issue when a car in front leaves your lane, VO TACC takes way too long to speed up.

I think it's somewhat better with the recent December 2021 updates, it doesn't wait as ridiculously long to start accelerating, but it's still too slow/gradual. It's definitely better about slowing down smoother at least. Before it would brake too late and too hard all the time, when approaching slower cars.
 
I didn't notice it mentioned there but the phantom braking is primarily a problem with the radarless cars that came from May 2021 and newer. I noticed when I was in the FSD beta, which disabled my radar and suddenly AP was unusable in certain situations so I opted out. It was night and day better as soon as radar was back. I don't know how we get Tesla to fix this but it needs to happen. Dumb cruise control is a band aid on a problem they introduced and I would rather they just fixed it, by putting radar back in if that's what it takes.
And FYI, you can still turn off your auto high beams by pushing away from you on the left stalk, you just have to do that every time you engage TACC/AP.
 
I didn't notice it mentioned there but the phantom braking is primarily a problem with the radarless cars that came from May 2021 and newer.
Not true, at least not true for all. Phantom braking has been an issue for my Model 3 since purchase in 07/2018, obviously a radar car with software that used it. While I did purchase FSD with the car (yeah, I know), I’m not in the Beta program and can’t speak to that. Phantom braking threads have been around since the Model 3’s introduction, with or without FSD, in or not in FSD Beta. We thought vision-only would fix the problem hoping that the radar was the issue. Is isn’t, or at least it isn’t all of the issue.
I don't know how we get Tesla to fix this but it needs to happen.
Yup, but based on the pervasiveness of phantom braking, Tesla either can’t or won’t fix it. Nothing has occurred that indicates Tesla even has phantom braking, ahem, on their radar.
Dumb cruise control is a band aid on a problem they introduced and I would rather they just fixed it, by putting radar back in if that's what it takes.
Agree, but a band aid that might mitigate the issue given Tesla’s propensity to not fix phantom braking. As to the radar, that may be just a band aid too or less, given PB in my radar-equipped car on all of its 86 software updates.
And FYI, you can still turn off your auto high beams by pushing away from you on the left stalk, you just have to do that every time you engage TACC/AP.
Yup.
 
I had a visual+radar model 3 before I decided to sell it (in this idiotic used car market) and bought a visual only MY, what a big mistake.

With a pure visual approach the car practically has near 0 depth perception and no 3d map of where things/cars are in position to the car. Cameras see a big something incoming and just goes bonkers on the phantom braking, the camera doesn't see anything and it goes bonkers. We need redundancy back or lidar/radar to give the system some 3d map/depth perception of where things are, not a picture of where things might be.

Yet Tesla's pushing this thought to folks that FSD could happen with just a pure visual approach...Yet it's been a known issue for months/years now and what've their supposed super awesome DOJO been doing with all the driving data? Absolutely nothing is being done.
 
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I just drove to work in my new 3, the first trip since the short ride home from the dealer. I gave up on cruise control after 10 minutes. I had the following distance set to the closest possible setting and it was still freaking out about cars changing lanes 30 meters ahead and hesitating when passing cars that aren't even in my lane. Got a phantom braking event on open interstate which is when I just turned it off and gave up.

In all my previous cars, I've used cruise control constantly. The most used controls in my car were probably cancel, +/resume, and -/set. I want some good-ol' dumb cruise control!
Future me here: When the update freeze finally lifted after MONTHS, things improved drastically and I use cruise control and autopilot all the time. However, my new issue is sometimes my wipers decide they need to full blast on clear sunny days. A couple times it was from a spot of dirt on in the camera area, but usually everything is clean and I just have to go without cruise control (which forces the wipers into auto) for a few days.

I'm starting to suspect a small spider may live in my camera area.
 
I just read your post. I have the same issue here in Norway, and it’s particularly bad on the E6 between Oslo and Lillehammer. Every time I drive this distance the car goes from 110km/h to suddenly 40km/h even when it’s registered the speed limit wrong at 80km/h. This happens in both directions as well. I have a brand new M3 2021, and I’m starting to miss my e-Golf and it’s reliability with cruise control and other features that my M3 has issues with.

I’ve contacted Tesla and got a time for a service later this month. The frustration is high with Tesla right now!
 
I had a visual+radar model 3 before I decided to sell it (in this idiotic used car market) and bought a visual only MY, what a big mistake.

With a pure visual approach the car practically has near 0 depth perception

The car has 50% more forward cameras than you do.

Why do you think it has no depth perception?


Attached is one of the slides from AI day, showing the results of radar vs. vision only for both speed and depth, as you can see the results are quite close to each other.

radarvsvision.jpg



Green is radar, orange is single-frame vision....video vision (what Tesla is using today) is blue
You can watch Teslas head of AI discussion this (with that chart) here:
 
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I just drove to work in my new 3, the first trip since the short ride home from the dealer. I gave up on cruise control after 10 minutes. I had the following distance set to the closest possible setting and it was still freaking out about cars changing lanes 30 meters ahead and hesitating when passing cars that aren't even in my lane. Got a phantom braking event on open interstate which is when I just turned it off and gave up.

In all my previous cars, I've used cruise control constantly. The most used controls in my car were probably cancel, +/resume, and -/set. I want some good-ol' dumb cruise control!
Wow I don’t use cruise control much but wanted to try autopilot on my M3 if it ever gets delivered - phantom braking is a serious flaw. - and goes against Tesla safety ratings - if I could find a better car to get I would -
 
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Newer software is not necessarily more reliable in this case. I had phantom braking on 2021.12.25.7, and I still have it on 2021.24.3. I’ve had it since I got the car three years ago and have had it through 75 firmware updates. Apparently not a huge concern for Tesla, just for those who experience it. Hate it. Phantom braking ruins an otherwise wonderful ownership and driving experience.
Hi will it hard break if autopilot is Off ?
 
How does it perform if you set the Forward Collision Warning to "Late" (which is obviously not ideal)? I'm assuming it's set to Medium at this point.

View attachment 690966
This isn't forward collision causing the issue. I disabled forward collision warning all together, still have the unnecessary/early/inappropriate braking issues. This is TACC freaking out when it shouldn't be.
 
The auto-brights on my model Y are a disaster. If I were in a car coming toward me, or a car ahead of me going the same direction, road rage would be a very likely response to the Tesla's auto-highbeam. And it should not be hard to get this right. My Mazda CX-5 did it absolutely perfectly 100% of the time. If there were headlights or taillights in front of me and less than about a quarter mile away, the lights were on low-beam. Always, and with no mistakes. If a car suddenly appeared in front of me from around a curve or over a hill, the brights were dimmed instantly.

The same is true with cruise control. The Mazda has TACC and does it perfectly. It also has ordinary CC for times when TACC isn't the best choice. TACC works best when traffic is relatively light.

With all of its intelligence, the Tesla is still very stupid about a lot of simple mundane things. It's frustrating.
Agreed