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Tesla Turns Off AEB In New Cars Produced Since July

Discussion in 'Model S' started by Economite, Sep 10, 2017.

  1. bcsteeve

    bcsteeve Member

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    I'm with you. My Google-fu says the only thing "continental" about a Tesla is (was) the rubber.
     
  2. brianman

    brianman Burrito Founder

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    I took a look at "a" Volt manual that I found online (no idea the quality or accurateness) but the description of "Forward Automatic Braking" didn't list any limitations (which is odd, presumably they have to cap it at some point as the sensors likely can't read quickly enough at max speed) but it did reference what appeared to be another document but I don't know how to find that document.

    If I search on (volt "forward automatic braking") just about every hit is preceeded by "Low-Speed" -- which seems to imply that they've extensively branded the feature with that full name -- i.e. low-speed only.

    More data...
    2017 Volt: Hybrid Electric Cars | Chevrolet
    There's a lot of wiggle room in "while following" and "detected". It might imply ACC on, it might not. It might imply it had to be a vehicle "in your lane" for some minimum period, which would exclude being cut off abruptly.

    Overall, I find their vagueness "uncomfortable" if I was looking into buying one.
     
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  3. brianman

    brianman Burrito Founder

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    I thought the air suspension too, but I might be misremembering.
     
  4. McRat

    McRat Active Member

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    Yes, I am 11,000 miles sure. Only ACC cars get radar. Without radar you get Low Speed AEB.

    It is not unusual to find GM understating their specifications.

    In California, including all taxes, fees, incentives, it was $28k fully loaded. It's a shop delivery car.
     
  5. brianman

    brianman Burrito Founder

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    I don't think (1) or (2) were in question. I think the question was/is whether AEB functions at high speed without ACC engaged. If it's only with ACC engaged, then the edge between "ACC braking" and "AEB braking at high speed" is blurred.
     
  6. McRat

    McRat Active Member

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    #246 McRat, Sep 13, 2017
    Last edited: Sep 13, 2017
    Since I don't use ACC (it wastes range) and the FCW comes on at freeway speeds, come to your own conclusion. My wife says she wasn't ACC mode.

    I think what is confusing you is how AEB systems are normally set up. If you push down on the accelerator you can override the AEB. If you release the accelerator, and do not apply enough force to the brake pedal, the car does it for you.

    2017 Chevrolet Volt
    2017 Tesla Model S
     
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  7. bcsteeve

    bcsteeve Member

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    Ok, I see where this goes off the rails. I (maybe) was wrong (at least for 2018 USA... I haven't cross-checked with Canada and/or 2017)

    Go to chevrolet.com Volt page and start to build/configure the car. Premier is required to get anywhere with this. Skip to "Exterior" and scroll down and you'll see two distinct options: "Low Speed Forward Automatic Braking" and "Forward Automatic Braking". The latter requires ACC, the former doesn't. However, while the low speed version is (obviously) for "low speed", that doesn't mean the other is for higher speeds! I stress this because in the info it states:
    That still doesn't sound very much like what Tesla offers.
     
  8. stopcrazypp

    stopcrazypp Well-Known Member

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    Good point. If it's the latter part, then it's not AEB with high speed, but rather just a function of ACC.
     
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  9. bcsteeve

    bcsteeve Member

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    No, no, no... coming to one's own conclusion isn't what we're trying to do. Nobody's trying to prove you right or wrong. The idea is to come up with THE conclusion, since GM apparently doesn't like to make things very clear. You can't (or shouldn't) assume your car will stop at highway speeds because some light comes on. I doubt you're willing to go perform a conclusive test for us :)

    Again, this isn't an argument so don't feel defensive. Just trying to close the gap between GM's information and your experiences.
     
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  10. stopcrazypp

    stopcrazypp Well-Known Member

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    The IIHS link doesn't help. There's only two tests, a low speed 12mph test (which Volt was able to prevent collision) and a 25mph (which Volt reduced collision speed by 5mph). Neither test tells you what would happen at highway speed. The Tesla wasn't even tested.
     
  11. bcsteeve

    bcsteeve Member

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    People keep pointing to the IIHS ratings. Standard testing is really only applicable when testing standard objects. Cars aren't "standard". Tesla may very well make the safest car on the planet and still score lower than a car that is less safe but panders to specific test outcomes. Yes, Tesla scores lower on IIHS than the Volt. I believe the Volt to be a very safe car. I can't believe it is as safe as the S, on the whole. Mass matters, first of all. But mostly its that massive crumple zone the S enjoys. The Volt still has a large hunk of metal between the driver and the impact.
     
  12. McRat

    McRat Active Member

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    You read it backwards. The Volt at 25mph reduced speed by 22mph or more, the highest rating. If it came to a complete stop prior to impact you cannot tell by their data, just that it was under 3.0 mph. They need a 4 point scale for DHS (Didn't Hit Sh*t).
     
  13. bcsteeve

    bcsteeve Member

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    #253 bcsteeve, Sep 13, 2017
    Last edited: Sep 13, 2017
    Um, no... that's not what it says.
    That's directly from the link you provided.

    What am I missing?

    Further, they discuss methodology and states that in the "high speed" (25 mph... so lol at "high") it got a score of 1 point out of a max 3, and it was some fraction of a mph away from getting zero points.

    Tbh... up until reading that, I thought the Volt's score was pretty good. But how can they give a "superior" rating for crash avoidance when in their own test results they showed it couldn't avoid a 25mph "high speed" (that's pretty low speed to me) crash and was less than 1 mph reduction from giving it zero points by its own criteria... yet that's "superior" where the S gets a big glowing yellow "acceptable" because IIHS failed to test the product fully (I realize they weren't given a version with AEB until a little while later, but its been months and they haven't updated it). After digging into this (thank you), I'm really starting to question IIHS's impartiality. Because that just doesn't make sense.

    During my test drive, I had the stupidity/balls/whatever to actually test AEB (and ACC combo). I had the car set to 70kph (roughly 44 mph) and I visually saw the cars stopped up ahead. I said "#$# it... let's see". Admittedly it waited within a fraction of a second of me panicking... but it stopped. I was just about to stomp on the brake, but it beat me to it and I never touched the pedal. It came to a complete stop with a good 3 to 5 feet to spare. It wasn't even a screeching halt or anything... it was abrupt, but not dangerous. I would have started stopping LONG before it did, but I was impressed.

    After reading IIHS's report... I'm sooooo glad I didn't make that same test in the Volt! Wow.
     
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  14. brianman

    brianman Burrito Founder

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    Regardless of how you interpret the 2x 2 sentences that IIHS has for the entries on their site, the fact that they consider 25mph "high speed" means that I find their testing useless for answering the highway speed question -- as @stopcrazypp notes.

    Do you disagree, @McRat?
     
  15. McRat

    McRat Active Member

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    The 2017 Volt scored 6 points:

    FCW - 1pt out 1 possible.
    Low Speed - 2pt out of 2 possible.
    High Speed - 3pt out of 3 possible.

    Look at the bottom for the chart:

    Front crash prevention tests
     
  16. oktane

    oktane Active Member

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    Thank you sir for coming to my defense. Yes he is name calling and being fairly rude and insulting. It reflects badly on him more than anything, but I understand that it's not really "him" posting here but more his online persona, as I'm sure he's actually not like this in person. Therefore I'm not offended.
     
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  17. brianman

    brianman Burrito Founder

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    For the 12mph test, you get 2 pts if you reduce the speed by 10+mph -- meaning you're going at 2- mph afterwards.
    For the 25mph test, you get 3 pts if you reduce the speed by 22+mph -- meaning you're going at 3- mph afterwards.

    2017 Chevrolet Volt
    Neither is a complete stop ("0mph afterwards"). Without a complete stop, I'm unclear how "avoids a collision" is the conclusion. Also, I'm unclear how you can conclude that even for a complete stop without knowing the stopping distance and the gap between vehicles when the braking was initiated.

    So basically, taking this and my other post, I'm thinking IIHS sucks with coming to conclusions in English.
     
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  18. McRat

    McRat Active Member

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    Beyond the IIHS testing all I can offer is anecdotal data.

    The LED FCW does operate at over 75mph. So the car knows there is a potential threat. This occurs at a range of 330' at 75 mph since the following distance maxes at 3.0 seconds. Will the car deliberately ignore the threat it successfully identified?
     
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  19. bcsteeve

    bcsteeve Member

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    Err.. what
    Wait, what? I clicked YOUR link and it clearly says it got 1pt out of 3 possible for "High speed" and goes on to say it reduced the impact by 5 mph... the bare minimum for getting 1 pt. What am I misreading????

    [edit]Ahhh... OK, I figured it out. I was clicking the sub-section "With Low-Speed Front Automatic Braking Only".

    I didn't realize the "Front Crash Prevention" main section was a result on its own.

    Sorry for the confusion.
     
  20. brianman

    brianman Burrito Founder

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    My car lights up FCW all the time without activating AEB. I hesitate to draw any conclusions without adequate testing (which I don't plan to do).
     

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