Brake system pressurizing every 11 seconds?

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by erick vazquez aguirre, Jan 25, 2019.

  1. erick vazquez aguirre

    erick vazquez aguirre Junior Member

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    Hello everyone, new to the forums have a 2012 Prius V, I do apologize if there is a thread out there on this issue . I have noticed my car making the buzzing noise of the i believe brake system pressurizing but it does it every 11 seconds give or take . It makes the noise when the car is on and parked , and when i drive . I dont think this is normal correct me if i am wrong , i started to notice this along with when i press the brake pedal lightly and not fully it makes a hizzing noise or some type of pump letting air out, i also feel it in the braking it is not as smooth as before , feels kinda bumpy braking at low speed.
     
    #1 erick vazquez aguirre, Jan 25, 2019
  2. bisco

    bisco cookie crumbler

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    welcome!

    not sure how often it should be pressurizing. it is possible you have a leak, or it could be normal.
     
    #2 bisco, Jan 26, 2019
  3. ChapmanF

    ChapmanF Senior Member

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    Well, when you take a car in for a software reflash, their instructions are to make sure the pump has just run before they start, and then count on it not to run again for the next 40 minutes or hour as long as the brakes aren't used, so a period of 11 seconds would be an outlier on that score.
     
    #3 ChapmanF, Jan 27, 2019
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  4. bisco

    bisco cookie crumbler

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    how many miles on her?
     
    #4 bisco, Jan 27, 2019
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  5. erick vazquez aguirre

    erick vazquez aguirre Junior Member

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    Thank you guys , it has 110,000 miles. I called a local prius independent repairman he said the ABS pump is going out and new it cost like $2000 but we can soruce a used one even tho they are hard to find as the prius regular and prius V are different pumps . I wonder why there is no recall on this ABS pump, i assume if the pump goes out i am out of brakes right ? the first 3rd gen priuses had a similar issue and had a recall.
    By abs pump does it mean abs accumulator ?
     
    #5 erick vazquez aguirre, Jan 28, 2019
  6. ChapmanF

    ChapmanF Senior Member

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    The pump and accumulator are in the same assembly. The assembly looks like two big round cylinders. One is the electric motor for the pump, the other is the accumulator.

    However, your leak might be in that assembly, or it might be in the actuator assembly (that's the other big brake assembly sitting on the firewall, has lots more tubes and wires coming out). You would be disappointed if you replaced one and then found out the leak was in the other one.

    With a leak big enough to make an 11 second cycle, I'd be willing to bet you can hear which assembly the leak is in, by touching them both with a mechanic's stethoscope in between pump runs.
     
    #6 ChapmanF, Jan 28, 2019
  7. bisco

    bisco cookie crumbler

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    there have been some extended warranties on certain years/models. probably depends on how many go bad
    you're fortunate to have a knowledgeable mechanic
     
    #7 bisco, Jan 28, 2019
  8. erick vazquez aguirre

    erick vazquez aguirre Junior Member

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    Thank you guys for all the input. Toyota only sells the pump and actuator as a whole so to get just the pump you have to buy used i am pretty sure. I wonder if i can repair the leak tho if it's air thats leaking out
     
    #8 erick vazquez aguirre, Feb 6, 2019
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