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2009 Delayed braking & dangerous .

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by MP3gee, Oct 13, 2020.

  1. MP3gee

    MP3gee New Member

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    I have a 2009 Prius that is experiencing severe brake delay issues, the driver reports it dangerous on both dry but worse on wet roads. would i be looking at the brake pedal position sensor as a possible culprit?
     
    #1 MP3gee, Oct 13, 2020
  2. JC91006

    JC91006 Senior Member

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    ask the driver did the severe brake delay come after they hit a bump on the road
     
    #2 JC91006, Oct 13, 2020
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  3. MP3gee

    MP3gee New Member

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    She can't recall if it happened after a big bump or not, but now it is constant.

    Also the car has now been sitting for about 6 months due to this very problem.. I was able to see that i think a tsb mentioned the brake accumulator as a possible culprit.
     
    #3 MP3gee, Oct 13, 2020
    Last edited by a moderator: Oct 13, 2020
  4. JC91006

    JC91006 Senior Member

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    If the brake actuator can't pressurize the brakes, you would get warnings on your dash.

    Have you gone to check the brakes? Maybe the brake pads are used up?
     
    #4 JC91006, Oct 13, 2020
  5. ChapmanF

    ChapmanF Senior Member

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    Is there a squirty sound when applying the brakes?

    A conventional car that badly needs the brakes bled just won't stop. The Prius brakes will still kinda sorta work, as there is a big pressurized fluid accumulator that can squirt enough fluid into the lines to squish the bubbles and apply the brakes. But it takes a moment. (Furthermore, if ever some other glitch is detected that drops the brakes into fail-safe mode, then it will be like a conventional car, and just won't stop.)
     
    #5 ChapmanF, Oct 13, 2020
  6. MP3gee

    MP3gee New Member

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    The driver stated she was having the braking issue prior to getting pads replaced & the pad replacement didn't help. Brake pedal is squishy & have to push it down really far & very slow to brake.
     
    #6 MP3gee, Oct 13, 2020
  7. MP3gee

    MP3gee New Member

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    Sorry I was just trying to see if one of you, would say 'this' or 'that' is very common on these. So if the pads have been recently replaced & that didn't help the issue. I will try to get a techstream & see what all the codes read. It might be a week or 2 before that happens tho.
     
    #7 MP3gee, Oct 14, 2020
  8. MP3gee

    MP3gee New Member

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    Ok so I test drove the car today, the vsc/brake light is on & the brakes grind but the pedal is firm. I'm thinking whoever did the brake job prior didn't actually replace the pads or even do a brake job.. just feels/sounds like your typical metal on metal rotor/worn pads. I am fairly versed in brakes & performance & have changed my fair share of brake pads/rotors & such. Upon feeling the actual front brake rotors they were worn indicating metal wear. So I will replace those. But bother to look at the back brakes & now I learn that the 2009 had a mid year brake change from drums to rotors, so I am stuck waiting for a picture of the rotor or drum to figure out what to order.
     
    #8 MP3gee, Oct 14, 2020
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  9. ChapmanF

    ChapmanF Senior Member

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    Did that really happen with the 2009 Gen 2 Prius, or is that just some catalog's way of showing the difference between the Gen 2 drums and the Gen 3 (first built in 2009, for MY 2010) discs?

    Seems like a quick peek through the spokes of a rear wheel would settle your question.
     
    #9 ChapmanF, Oct 14, 2020
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