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Pre-collision Braking

Discussion in 'Prime Main Forum (2017-2022)' started by ukr2, Feb 6, 2017.

  1. ukr2

    ukr2 Senior Member

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    Who has experienced the Pre-collision Braking System?
    I assume in avoiding an accident.
     
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  2. ForestBeekeeper

    ForestBeekeeper Active Member

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    Anytime you use the cruise-control, it is watching vehicles or objects in front of you. When vehicles slow down or pull out in front of you the vehicle automatically brakes to maintain distance.
     
  3. ttait

    ttait Active Member

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    While driving through Los Angeles towards the grapevine in stop and go traffic in the pouring rain, I experiences the braking system.
    One the one hand, it worked. On the other, I found that it applied the brakes earlier than I wanted at very slow speeds. If the car in front of me stopped, and I was still moving to close the distance, the automatic system essentially jammed on the brakes. I found it abrupt and somewhat disconcerting.
    I found that the only way to keep from getting jerked around was to keep my foot on the brake pedal, because it won't activate while you're braking.
     
  4. Wattup

    Wattup Junior Member

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    Good to hear tpps working. Should save people tons of money by avoiding a collision. Ive only gotten the display to come on telling me to stop. Ive tried to test it but either im too chicken or it needs to be super close for it to engage the brakes ^^

    Posted via the PriusChat mobile app.
     
  5. CaliforniaPrius

    CaliforniaPrius Active Member

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    I am planning to buy some balloons and tape them to the ground. That way I can test out the precollision system. It's been raining nonstop these days. Didn't have the chance.
     
  6. ForestBeekeeper

    ForestBeekeeper Active Member

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    It is monitoring the distance between vehicles, keeping the minimum legal distance. You and I [and most everyone] are accustomed to tail-gating. The proper amount of distance would allow other vehicles to slide into that open space.

    :)
     
  7. MNdriver

    MNdriver Senior Member

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    Only if you're using cruise control?
     
  8. ForestBeekeeper

    ForestBeekeeper Active Member

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    As far as I know.
     
  9. priuscatprimeguy

    priuscatprimeguy Senior Member

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    It would be pretty annoying if it braked while not in cruise control.:D
     
  10. Wattup

    Wattup Junior Member

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    Im not fully sure if this video is talking about the features of TPPS in our Prius but it seems you don't have to be in cruise control to activate the emergency braking.

    EDIT: Pedestrian detection is included on all Prime models.

     
    #10 Wattup, Feb 7, 2017
    Last edited: Feb 8, 2017
  11. Lee Jay

    Lee Jay Senior Member

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    It would be even more annoying if it didn't.

    It's designed to prevent accidents, whether you're in cruise control or not.
     
  12. priuscatprimeguy

    priuscatprimeguy Senior Member

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    I disengage my cruise control when I come to a red light to avoid the annoying braking of DRCC. So no, I disagree that it's more annoying
     
  13. Lee Jay

    Lee Jay Senior Member

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    If it only works in cruise control, there's no point in it existing.
     
  14. bowang

    bowang Member

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    Please let us know if it work. And be careful not too fast to avoid deploying air bag.
     
  15. priuscatprimeguy

    priuscatprimeguy Senior Member

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    you did notice I said DRCC? Not pre-collision braking system?
     
  16. Lee Jay

    Lee Jay Senior Member

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    The topic of this thread is the pre-collision braking system, and the people discussing it to which you responded were also discussing that system. Someone thought it was only doing it while DRCC was on, but that isn't the case.
     
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  17. Tideland Prius

    Tideland Prius Moderator of the North
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    Nope. Hope to never have to use PCS Braking. Someone did do a Gen 3 test but that video has been taken down since. The Gen 3 isn't as sophisticated as the Gen 4's but there's plenty of video around from the media event testing the system.
     
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  18. crewdog

    crewdog Acting Ensign Prius Prime

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    While using the DRCC, and a vehicle in front slows down, the car will decrease power or brake to maintain a 1, 2, or 3 bar distance. Don't know about emergency situation though.

    While operating one day normally, without DRCC, in "urban rush hour combat" I had a car cut in front and brake suddenly, and got a big red warning sign "Apply Brakes Now!" or some such, and a loud beep on the display at the same time I applied full stomp on the brake pedal. I can't say for sure if the vehicle braked or not, but I can definitely speak for the warning.

    In normal traffic it seems that approaching another vehicle from behind with the brakes already applied does not trigger the warning; maybe the computer senses the vehicle deceleration.
     
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  19. Since2002

    Since2002 Senior Lurker

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    Hard braking shouldn't trigger the air bags. It requires the type of near-instantaneous deceleration that occurs most commonly by colliding with a massive object. Which the system then compares with data collected from test crashes. So I doubt there is much risk from making a full-speed run at some balloons.
     
  20. RJ Primw

    RJ Primw Member

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    Pedestrian detection is only on the Advanced.