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enabling DRCC slams on brakes...

Discussion in 'Gen 4 Prius Main Forum' started by spencer02, Apr 18, 2020.

  1. spencer02

    spencer02 Junior Member

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    Earlier today I was in traffic going about 25mph on the freeway, I was more than a car's length away from a semi truck. When I enabled DRCC my car instantly pressed all the way on the breaks.. very un-safe, almost caused me to get rear ended. I quickly disabled and haven't tried it since.

    I've used DRCC in traffic below 10mph in the past and never had this happen... Any ideas to why this happend? Should I have my car inspected by Toyota before I use the feature again?
     
  2. Tideland Prius

    Tideland Prius Moderator of the North
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    That is what I would’ve expected it to do. It’s trying to keep the distance that is set (which is 3 bars). When you first turn on DRCC, it’s set to 3 bars which is more than a car’s length. In a scenario like yours, I usually turn on then adjust the distance setting before I set the speed.
     
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  3. spencer02

    spencer02 Junior Member

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    I guess that makes sense.. thanks for explaining.
     
  4. pianewman

    pianewman Active Member

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    ...and I would never turn it on while that close to another vehicle. Sounds normal to me, too.
     
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  5. alanclarkeau

    alanclarkeau Senior Member

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    I'd expect that too, travelling so closely. I leave mine on all the time, it'll occasionally mis-read, but you can usually understand why. A motorbike changed lanes across in front of me recently, closing the gap as he did his ridiculous manoeuvre, and she displayed BRAKE.
     
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  6. sclevine

    sclevine Active Member

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    It's not the best DRCC out there. I've driven in rental cars where the adjustments adjustments are waaaay smoother. The braking in this implementation can be jarring sometimes, and often times unnecessarily. But I've gotten used to it and am quick to shut it off if it starts decelerating unnecessarily, and then turn it right back on when the condition clears. I also adjust between 1, 2 and 3 bars depending on traffic. On 3 bars, it tends to leave pretty big gaps that other cars use to cut, which then causes the DRCC to hit the brakes - can be super annoying sometimes.
     
  7. kithmo

    kithmo Couch Potato

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    Too close to the car in front, or approaching the car in front too fast.
     
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  8. Mendel Leisk

    Mendel Leisk EGR Fanatic

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    It's trying to tell you something.
     
  9. Mambo Dave

    Mambo Dave Active Member

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    Wasn't the safety recommendation to be to count 1 second distance for every 10 MPH in speed?

    So if you were traveling at 40 MPH, you should be able to count four entire seconds before crossing the same spot of the vehicle ahead of you. Any closer, and you're the problem on the interstates.
     
  10. Mendel Leisk

    Mendel Leisk EGR Fanatic

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    I thought (minimum) 2 seconds, at any speed. I like 4 seconds, allows you to stay off the brake more, improves the odds.
     
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  11. Mambo Dave

    Mambo Dave Active Member

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    There is no set time to go by, nor should there be. The distance is determined by the speed the driver is operating the vehicle at. Driving at 100 miles per hour, which my Prius will easily hit, means keeping a longer distance for a margin of safety from those ahead of me. (i.e. if I don't have wide open spaces with minimal traffic to be doing 100 MPH, then I have no business doing 100 MPH)

    Operating a vehicle is a complex skillset, and I really appreciated when our testing centers failed testees - then did not issue driver's licenses - to those who could not grasp the concepts or prove their worth in a closed-course. Apparently that didn't work for certain groups, so now just about anybody can get a driver's license.
     
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  12. ETC(SS)

    ETC(SS) The OTHER One Percenter.....

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    Asked and answered.....
     
  13. kithmo

    kithmo Couch Potato

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    True but a time, like two seconds, is easier to judge for some people than distances and obviously as the speed increases then the distance will increase for the same time.
     
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