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Brakes engaging very strongly

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by JasonWSVT, Mar 31, 2014.

  1. JasonWSVT

    JasonWSVT New Member

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    Hey, I'm been having trouble with my brakes since last night. If I press very lightly on them, the car gently slows, but if I press very slightly more, the car slows rapidly - it seems like the wheels lock out, and there's a noise that seems to originate from the rear right wheel. Any ideas?

    Thanks,
    Jason
     
  2. GrumpyCabbie

    GrumpyCabbie Senior Member

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    The rear brakes in a gen2 Prius vary depending on Country (some have discs and pads, others drums)

    Update your profile to include Location and you'll get a much more accurate response. (y)
     
  3. Easy Rider

    Easy Rider Active Member

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    You might indeed have one brake locking up.......and if you have ABS, that might be the noise you hear.

    Don't delay having this looked at. If one brake is not releasing all the way it could get hot enough to start a FIRE. :eek:
     
  4. dorunron

    dorunron Senior Member

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    My best advice would be to have the system checked by a professional. Prius brakes are specialized. Not many know how to bleed them properly.

    I would suggest you visit a local Toyota dealer and ask for the brakes to be inspected and then go from there.

    Best of luck to you and "Welcome to Prius Chat"!

    Ron (dorunron)
     
  5. olerox

    olerox Junior Member

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    Hi Jason, One chronic problem with rear brake behaviors in my wet Northern Oregon is at slower speeds the rear brakes will grab sharply during morning drive.

    Try this for a cheap, fast test. In safe area, get the your Prius up to 35-40mph and then hold the shift to "N" for a couple seconds to get into neutral, then apply your brakes gently and increase pressure until you are at a stop. Then test again under the conditions you've noticed the lockout and noises.

    Aparently if there is the tiniest rust from dampness during the night the drum brakes/shoes will grab abruptly until they've made some contact which is only done under 17mph or when car is in neutral I hope this helps.
     
  6. JasonWSVT

    JasonWSVT New Member

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    Thanks, everyone! When I got out of work and tested the brakes, they were fine, and have been fine since.

    Jason
     
  7. Britprius

    Britprius Senior Member

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    I do not know if this is a misprint, but the Prius brakes come on at 7 mph not 17 mph. All other information is good for American continent Prius.

    John (Britprius)
     
  8. edthefox5

    edthefox5 Senior Member

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    Olerox hit it I bet.

    Please take a look at the front brake rotors through the spokes of the wheels and see how rusted they are. If your not regularly cleaning the brakes using Olerox's method they will get really grabby especially living outdoors in VT which like Florida have very wet evenings. This constant soaking will really corrode the rotors and make them incrdibly grabby especially after a rain. They may be so corroded they need to be replaced. I'm from Bennington btw.

    I am in such habit of cleaning my brakes I watch the battery meter and if its in green approaching a light I pop the car in neutral and clean the brakes as I approach the stop. Remaining in neutral through out the light then shift into D and drive away.
     
  9. edthefox5

    edthefox5 Senior Member

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    The normal hydraulic brakes are always functional just regen assist stops contributing at 7 mph or below.
    Then its 100% hydraulic friction brakes.
     
  10. imadadoftwo

    imadadoftwo New Member

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    I am trying to figure out this 'grabby brake' issue too - but I'm in the desert valley of Phoenix, Arizona. Humidity is not really a factor. I have an '05 with 193k miles and just a week ago it started this grabbing at low speeds, a making slow manuevers into parking spots VERY difficult. Took it to my Toyota service center and they couldn't find the problem, but said it had stopped after they checked the 'black box' and retested everything. He also said it was the regenerative brake system causing the grabbing. According to them, I am braking while stopped, accelerating while stopped and braking and accelerating simultaneously (two-footed driving). Something I would NEVER do as it is so dangerous. Well, it started again within 5 minutes of leaving the shop.
    I am taking it back tomorrow and suggesting they check for rust on the rust on the pads. See what happens. In nearly 10 years and 200k miles we've hardly had a problem with ole reliable "Sparky"...here's t'hopin'.