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Car slammed on its brakes on its own

Discussion in 'Gen 4 Prius Main Forum' started by 2020XLEAWD, Apr 2, 2021.

  1. 2020XLEAWD

    2020XLEAWD Member

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    I was driving about 35 mph when a jogger peaked around a parked car to wait for cars to go by and cross. My car sensed this person and SLAMMED on the brakes, almost causing the car behind me to rear-end me. How do I keep the red brake warning on the dash but turn off the computerized braking?
     
  2. bisco

    bisco cookie crumbler

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    ah, the joys of semi functional high tech
     
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  3. jdenenberg

    jdenenberg EE Professor

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    I don't believe that you can disable this safety feature. Toyota has very conservative attorneys and their designs always default to their perception of safety. Note that if that pedestrian had walked out in front of you the system would have limited the injury or even avoided it. Your response time may not have done as well.

    JeffD
     
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  4. David9962000

    David9962000 Member

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    You can adjust the sensitivity to short, medium and long on the steering wheel settings. Medium is standard and everytime you turn it off and system comes back on.
     
    #4 David9962000, Apr 2, 2021
    Last edited: Apr 2, 2021
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  5. hill

    hill High Fiber Member

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    What, you've only had this happened one time?

    I'd wonder if the system was working if it wasn't happening at least once a week. Typically it's at night - slow curve towards driver's side - & it sees an upcoming parked car on the passenger side - & thinks I'm headed right for it.
    On our tesla, it would think an overpass was a stopped vehicle & hard braking would ensue.
    .
     
  6. PaulDM

    PaulDM Active Member

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    In the UK there are two settings that affect the automatic braking

    pre-collision system and pksb

    I'm not suggesting you turn them off but settings are available

    BA97E4DA-5A89-4395-BEE3-FDB60329231D.jpeg D331E844-999E-4FFE-91A2-BEA255112372.jpeg
     
  7. vvillovv

    vvillovv Senior Member

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    IMO - it was just the car screeching at you :GET TO KNOW ME" ! Ever owned another car that did that kinda thing in other ways?

    On the good side ??
    This forum might have saved you a couple hundred $ in possible diagnosis and/or repairs from a dealer, after presenting the car to them with the same question you posted here.

    Welcome to the world of Hy Tech and it Only Happened Once? :D
     
  8. dbstoo

    dbstoo Senior Member

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    These safety devices are now being mandated, so as time goes on you'll see more and more cars doing virtually the same thing.

    The down side: It's scary when the car applies the brakes in a situation where you'd normally just watch the person.

    The Up side: If the person stumbled, tripped or otherwise walked out between the cars you would have already slowed down and car->human impact will be minimized.

    The other upside: As more cars get these features, the car behind you will be able to respond quickly when your car applies the brakes, preventing that rear ender that you were afraid of. Using radar (as the Prius does) allows it to figure out whether or not to hit the brakes even if the brake lights of the car ahead of you are broken or obstructed.
     
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