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2013 Prius V - Brake Booster?

Discussion in 'Prius v Care, Maintenance and Troubleshooting' started by GigglingPresident, Mar 28, 2021.

  1. GigglingPresident

    GigglingPresident Junior Member

    Joined:
    Mar 21, 2017
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    Location:
    St. Pete FL
    Vehicle:
    2013 Prius v wagon
    Model:
    Five
    Greeting Forum:

    Vehicle specs:
    2013 Toyota Prius V
    Mileage: 90,000
    No prior accidents

    My wife Prius V started to make this hissing sounds for past 8 month and finally yesterday ABS light came on. This happened when she was coming of at angle from the ramp. Now when you turn engine on, you can hear every 5 seconds brake booster to kick in. I started to read little bit about this problem and it seems like its a known issue but hard to get Toyota to pay for replacement.

    I will post a short video with a screenshot of the dashboard when engine is running. Unfortunately I do not have a way to capture codes but maybe you can suggest what device to get or just go to AutoZone.

    Should I go with this issue to the dealership and hope they can cover it under "Customer Support Program ZJB" or find a reliable mechanic in Pinellas County FL area? If someone can suggest repair shop that would be great.

    Also, does anyone has a good guide on how to replacing brake booster or should I stay away because of code reader and special tools requirement. I have replaced brake boosters in the past but never on a Prius.


    Thank you
     
  2. GigglingPresident

    GigglingPresident Junior Member

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    Vehicle:
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    Five
    Here is short video of my problem:


    [​IMG]
     
  3. Air_Boss

    Air_Boss Senior Member

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    Why would you not ask about ZJB?
     
  4. ChapmanF

    ChapmanF Senior Member

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    Vehicle:
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    The "brake booster" doesn't make any sound you can hear, and it only operates when you push the pedal. The sound you are hearing is the "brake booster pump". Yes, those are the real names of two Prius parts that are different. Yes, the naming situation is bananas.

    [​IMG]

    The "brake booster" assembly (top picture) also contains some electronic valves in addition to the booster, and sometimes you can hear those faintly clicking. But the repeated whirring pump sound you hear is from the "booster pump" (bottom picture).

    The tricky bit in diagnosis is that the cause of the repeated pump cycling can be in either assembly.

    If it is actually cycling as often as five seconds, a simple mechanics' stethoscope ought to let you pick up a hissing noise during the five seconds off, from one of those assemblies or the other. I'm thinking any internal leak fast enough to cycle the pump at five seconds will be audible in a stethoscope. With a normally functioning system, you get bored waiting to hear the pump run again.

    If there is a chance campaign ZJB will cover it, I don't see a reason not to ask. You get shiny new parts, and somebody who isn't you does the labor (and the labor is a pain).
     
  5. rjparker

    rjparker Tu Humilde Sirviente

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    Vehicle:
    2012 Prius v wagon
    Model:
    Three
    If you have codes, don't clear them. Take it to the dealer. Your noise sounds like a totally failed part.

    When my Master Cylinder and Pump were failing, the pump would cycle every twenty seconds if the brakes were applied. Which means it actually reached its shutoff pressure within that time frame. This behavior did not qualify for Toyota funded replacement. It needed to run for several minutes to trip a code. Essentially, if the brakes were working and were not operating in a reduced failsafe mode, they were ok per Toyota.

    After I had a Master Cylinder Assembly and a Pump Assembly installed, the typical Pump run time was approximately ten seconds. Usually once in the morning as the car sensed my keyfob and once after applying the brake.

    Prius master cylinder assy.jpg Prius pump assy.jpg
     
    #5 rjparker, Mar 28, 2021
    Last edited: Mar 28, 2021
  6. GigglingPresident

    GigglingPresident Junior Member

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    Vehicle:
    2013 Prius v wagon
    Model:
    Five
    Thank you for fantastic feedback. I know more than any just which I can read those code but that for me to discover on this forum on what to use. Tomorrow I am taking our V to nearby Dealership service dept and we will see. Hope they will give me honest feedback with all codes that I have not cleared.
     
  7. GigglingPresident

    GigglingPresident Junior Member

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    Five
    Reporting back. Toyota dealership notified me that my scenario falls under "Customer Support Program ZJB" . It had all proper codes so if anyone else is experience this issue, please do not clear them. Another interesting thing I heard from this service Dept is that one customer came in with same hissing sounds but no codes, this customer was suggested run their Prius overnight and sure enough codes showed up in next 12 hours. It might be worth trying.

    Side note: I have looked into techstream cost and my goodness. Still researching on alternatives for scanner but techstream seems like what Toyota Service Depts are using.

    Thank you again
     
    Mollyisadog, rjparker and Air_Boss like this.