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Brake computer temp loss

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by ramattos, Nov 5, 2014.

  1. ramattos

    ramattos Junior Member

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    Recently went over a decent bump in the road and while braking had the regen disengage and the conventionals kick in differently. It was like they switched to normal. I know that. On some bumps it disables regen and flashes the skid light on the dash, but this was different. Hit the bump while braking and the pedal went halfway down and then started responding. Not like the normal regen less braking where you press harder and it still slows, this was almost like at that point it became over sensitive where the slightest touch more felt like the wheels would lock or grab extremely hard. Should add that during this time the light didn't flash on the dash, nor was a error shown on the screen.

    The closet thing I can think of is that it's like driving a conventional car with the engine off and no vacume on the booster, but even that isn't right.

    I know that what I'm trying to describe sounds like a normal operation but it wasn't. It's just hard to describe.

    Has anyone else had this situation?
     
    #1 ramattos, Nov 5, 2014
  2. bisco

    bisco cookie crumbler

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    nope. report to nhtsa?
     
    #2 bisco, Nov 5, 2014
  3. Mendel Leisk

    Mendel Leisk Senior Member

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    We get that behaviour, not frequently, but pretty regularly: always just after startup, in reverse. Seems like there's NO modulation: touch the brakes and it's nearly locked. Goes away once we get out of reverse, get going.
     
    #3 Mendel Leisk, Nov 5, 2014
  4. Mendel Leisk

    Mendel Leisk Senior Member

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    Had something like that, maybe 2 months back. Backing out of the garage, and for a split-second the brake pedal dropped, there was a weird loss-of-braking feel, and immediately thereafter a warning came on: "CHECK HYBRID SYSTEM". Took it to the dealership (warning persisted for the drive there). They did some tests, dismissed the codes, found nothing, told me to keep an eye on it.

    They did manage to leave the hood support rod loose, which freaked me out when I was leaving the dealership, it started rattling like crazy. Keeps you on your toes.
     
    #4 Mendel Leisk, Nov 5, 2014
    Last edited: Jan 21, 2015
  5. ramattos

    ramattos Junior Member

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    That's the unusual part for me, no codes or lights went on.
     
    #5 ramattos, Nov 5, 2014
  6. Christian_cool

    Christian_cool Junior Member

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    I have also experienced that with my car the last 2 month when passing over bumps. I took it to the dealer and they said that this is "normal".. for me this isn't normal for a car. This is just software that needs to be improved to avoid these fault, that can in worst lead to an accident.
     
    #6 Christian_cool, Nov 5, 2014
  7. bisco

    bisco cookie crumbler

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    was there a software flash for this?
     
    #7 bisco, Nov 5, 2014
  8. Jonny Zero

    Jonny Zero Giggidy

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    I have noticed "incorrect" modulation after the car has been parked in the rain for a while and the rotors get a layer of rust on them. The brakes are more touchy and feels non-linear. But then it probably would on a conventional car too.
     
    #8 Jonny Zero, Nov 5, 2014
  9. bisco

    bisco cookie crumbler

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    i agree, and the prius rotors are soft and tend to rust more because they don't get used that often.
     
    #9 bisco, Nov 5, 2014
  10. stuartdole

    stuartdole Junior Member

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    I've had this several times - hit either a bump or pothole while braking and it feels like the brakes completely fail. I haven't tried to "just stomp further" - my instinct (from conventional non-ABS cars) is to completely let up on the brakes and press again, and they engage OK. This seems to be a design error of some sort, and it's really scary.
     
    #10 stuartdole, Jan 20, 2015
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