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loss of brake boost after warm start

Discussion in 'Prius v Care, Maintenance and Troubleshooting' started by jonb505, Apr 17, 2015.

  1. jonb505

    jonb505 Member

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    2012 Prius v wagon
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    Not a major concern, just something I noticed and could not find any other thread discussing it so I thought to bring it up.

    So it usually happens after power on when the engine is warm(warm enough that the ICE does not fire up until needed).
    As an example, I drove from home, parked at the mall, got back in after an hour or less and power on(engine is still warm so ICE does not start). foot on brake pedal, power on, reverse, car starts rolling back with brake pedal almost to the floor. Brakes work, but very touchy, on/off feeling with no resistance/modulation in the pedal. After getting up to speed brakes return to normal operation.
    The feeling of the brakes is very much like when braking at speed using regen and hitting a pothole and feeling that temporary loss of braking as the regen shuts down and friction brakes take over 100%.
    Is this just an anomaly of the electric brake booster pump or is something wrong with my brakes? I've kinda gotten used to it now but it still catches me by surprise and freaks me out sometimes. :eek:
     
  2. jonb505

    jonb505 Member

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    Location:
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    Vehicle:
    2012 Prius v wagon
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    N/A
    Ok after searching I discovered this is a common issue. Sorry for starting a new thread. :oops:
     
  3. bisco

    bisco cookie crumbler

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    you don't consider brake issues a major concern?:eek: