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Power Cuts Out When Traction Control Kicks in - Dangerous????

Discussion in 'Gen 2 Prius Main Forum' started by Grzldvt, Feb 28, 2023.

  1. Grzldvt

    Grzldvt Junior Member

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    I have a second home near Yosemite and CA is having huge, nasty storms and in my case a lot of snow at 3000 feet.
    Car handled the snow just fine until I came to my last very, very steep hill that has a 90 degree turn in it.
    Snow was about 5" and what few tracks that were clear of snow were icy. I sped up knowing I would lose momentum and had to be very careful I did not slide into oncoming traffic on the 90 degree turn, but did not over do it. Traction Control kicked in and the car slowed to a dead stop about 200 feet from the top. Really the car stops???? I am now sitting in the middle if the road on a very steep hill. I could not get it to move. Holy crap this is ridiculous???
    I finally had to put the chains on just to get it to the top. The rest was downhill and flat, but I left the chains on just in case I needed traction. Never drove any car in my life that cut power to zero when traction Control kicks in. Wth am I missing
     
  2. Tombukt2

    Tombukt2 Senior Member

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    I rarely drive the Prius and snow even in North Carolina power will cut out in the rain if the tires get to slipping enough so the trick is is you've got to get your foot off the gas once traction breaks well pretty much not anything is going to happen from what I have seen I have not tried to do this a lot when I'm going down the road early morning on Frost heaves just going over little undulations in the road If I don't slow down and keep trying to do 55 60 miles an hour on back roads every time the VSC or is it the! Whatever the traction business starts flashing on and off in tandem with the breaking of traction so as I'm going down the road hitting the frost heaves in between real pavement I see the light bouncing on and off and every time I see that light bouncing the car bounces or undelays because the traction control is going crazy trying to find traction I guess. It did this when I had a different series tire on the front and the back it made the car unusable and almost not able to get the 55.
     
  3. bisco

    bisco cookie crumbler

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    Yeah, that’s a known problem to protect the transmission lines
     
  4. dolj

    dolj Senior Member

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    Yeah, that’s a known problem feature to protect the transmission lines
     
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  5. Leadfoot J. McCoalroller

    Leadfoot J. McCoalroller Senior Member

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    It did what it was supposed to do.

    It's pretty good at finding traction if you apply partial power and wait.

    Quite a few cars behave similarly now.
     
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  6. ChapmanF

    ChapmanF Senior Member

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    Yes, the algorithm in the traction control kind of depends on the human to be giving consistent input that is reasonable for the conditions. So don't, like, reactively back way off the go pedal when the TC kicks in; the computer still needs to know you would like to go forward. But also don't have the pedal mashed farther down than you could ever expect the available traction to support. If you're using reasonable judgment about your pedal input versus the road conditions, the TC can help you around the margins of that. If you're giving a pedal input massively out of line from what road traction is available, the TC is likely to try what you seem to want, and get caught between taking great big digs and backing off, which doesn't turn out to work well.

    What you want to do is look like one of these two cars (one a Gen 3, one a Gen 2). Both drivers were probably just holding the pedal steady at a level that was pretty close to appropriate for the conditions, and letting the TC find the edge.




    Adding the chains wasn't a bad idea; sometimes the available traction just doesn't give you or the TC much to work with, and then changing the available traction is the winning play.
     
  7. edthefox5

    edthefox5 Senior Member

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    yeah its pretty disconcerting the first few times it happens. Not a good feeling.
     
  8. Savannah Dan

    Savannah Dan Junior Member

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    It's the only thing I really, really dislike about my Prius. A little sand on asphalt trying to pull onto a road with traffic coming = extream pucker factor.
     
  9. Tombukt2

    Tombukt2 Senior Member

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    If you practice with it you'll get used to it and you can launch and that kind of stuff reasonably well as long as what you're launching on to has the traction you need and obviously you need to have time to do so before the car coming down the road slams into you I mean if you had more amazing traction in a little more power you'd get out onto that road quicker but that person coming down it would still have to break pretty stoutly while you're trying to speed up. It seems to me anyway
     
  10. Stevewoods

    Stevewoods Senior Member

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    Very dangerous and very stupid. Yhe TC, not the OP.

    Yeah, Hated that "featurre"
     
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  11. Stevewoods

    Stevewoods Senior Member

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    Sorry for the typos. My wife and kids are trying to push me into the digital age and are forcing me to use my phone to web surf. You can see the results --for what it is worth, this post is from a desktop computer.

    But, I don't understand the current acceptance of the TC situation. Back in the early days of this board, people ranted, ranted, ranted about the TC.

    What, we should, without any warning from Toyota, all of a sudden -- on our own -- while driving -- become aware the car may stop in the middle of a slippery intersection and refuse to go any further. Luckily, I was a member here and read about the problem before I encountered it, but it did not make it any easier to deal with when it finally did happen, ]
     
    #11 Stevewoods, Mar 4, 2023
    Last edited: Mar 4, 2023
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  12. Leadfoot J. McCoalroller

    Leadfoot J. McCoalroller Senior Member

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    I guess I don't get the big deal on traction control.

    I don't know of a modern car that does traction control differently, and I have a hard time seeing the benefit of a car dynamically proving it has no traction vs. a car that has sensed that it has no traction and cut back the power. I mean maybe there's some benefit in everyone else seeing your wheels spinning, so they understand you're disabled/out of control?

    Nobody should be attempting a Scandinavian Flick in traffic anyways.
     
  13. Stevewoods

    Stevewoods Senior Member

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    I guess the deal is, and I could and probably am, wrong.....but I have been driving a long time and have lost traction many times, but have many times -- not always-- but many times -- been able to finesse my way out of the problem.
    But the Prius TC did not seem to allow me that option. Maybe I did not do it right, would not be the first time. I am no pro driver.

    My other cars, lost traction, I feathered, prayed, cursed, and often times you were back moving. Prius, seemed and maybe it is only me, but previous posts from others in 2008 on seemed to echo. Oh, sure, maybe you could get it going but it seemed to be a big hassle. Maybe we should have read the manual. Not saying Toyota did anything wrong. Just saying some of us could not figure out what to do.

    Again, could have just been me and probably was
     
  14. Leadfoot J. McCoalroller

    Leadfoot J. McCoalroller Senior Member

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    Well, I will admit to not reading the manual either but only because I'd read about how to deal with modern TC on a different forum years ago.

    And the "what to do" is pretty different that you'd do in older cars, so there's that. Just hold the throttle steady at about 1/3, give the computer time to feel it out and be ready to steer. Don't move your foot.

    The thing that helped me the most in actually using modern TC is the understanding that low-traction driving means you need to allow for much longer reaction times from the car. And the car is doing it that way because that's all the surface will support.

    It's not really slower at getting you out of the next guy's way vs. an old-school car, it's just that your workload is much lower so it feels like ages are passing while it scratches and crawls along.

    And remember, you are in very good company. They made a heck of a racket on the Subaru forums when the feature came to that brand around 2002. Pretty much every car does it this way now.
     
  15. dbstoo

    dbstoo Senior Member

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    I had the same experience with a 2010 Cadillac Deville. An unexpected snow storm left us stranded, unable to climb a steep 400 foot long incline that led to our home. The tire tracks showed that someone had made the attempt and made it. Other tracks ended at the cars and SUVS that were parked at strange spots part way up the road.

    I tried it using the OP's technique and came to a stop just short of the top. I had to back down the hill.

    I knew that the tires needed to be upgraded, so I found a tire dealer that sold us some good rain/snow tires. The tires made all the difference. Where I had problems before the car was able to proceed without problems if I took it slow and easy.