1. Attachments are working again! Check out this thread for more details and to report any other bugs.

2 unusual sound need explanation

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Eric Vasaio, Jul 17, 2019.

  1. Eric Vasaio

    Eric Vasaio New Member

    Joined:
    May 14, 2019
    11
    8
    0
    Location:
    BC, Canada
    Vehicle:
    2013 Prius Plug-in
    Model:
    Plug-in Base
    So I've got this 2013 Prius 2 month ago. I always hear these 2 sounds from this suppose to be very quiet car. I tends to think they're just normal sounds but...

    First, humming electric motor sound. Especially under low speed and gentle brakes, I can hear this bee humming sound relatively loud. If you have an old style not well lubricated electric fan in summer time, that's the sound.

    And then, every time, about 1 minute after I shut the car off, there's always a clunk sound from front of the car, maybe from under hood, or maybe from brakes which is really hard to tell. As if two metal pieces get engaged or disengaged.

    Are they normal Prius sounds? thanks for any input.
     
  2. tankyuong

    tankyuong Senior Member

    Joined:
    Nov 9, 2012
    1,555
    659
    0
    Location:
    Central MO
    Vehicle:
    2012 Prius c
    Model:
    II
    Sounds normal to me
     
    Eric Vasaio likes this.
  3. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    107,571
    48,862
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    i would take it back to the dealer for warranty repair
     
    Eric Vasaio likes this.
  4. ChapmanF

    ChapmanF Senior Member

    Joined:
    Mar 30, 2008
    23,073
    14,980
    0
    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV
    Self-test of brake system, couple minutes after power off, every time. If you listen carefully, it's more than just "clunk", but more like "clunk ... clickity squish ... squish clunk".

    Utterly normal.

    Sometimes, it will need to repressurize during the test, so you'll hear the brake pump too ("whirrrrRRPclunk"). Not every time. Depends on what the accumulator pressure happens to be when the test starts. Don't be concerned because you do or don't hear it every time.

    If the car detects any problem, it'll tell you. That's why it self-tests. No news is good news. :)

    Whatever you're thinking, you did not just read this same explanation in some other similar-looking thread. Have you tried getting more sleep?
     
    Eric Vasaio likes this.
  5. Eric Vasaio

    Eric Vasaio New Member

    Joined:
    May 14, 2019
    11
    8
    0
    Location:
    BC, Canada
    Vehicle:
    2013 Prius Plug-in
    Model:
    Plug-in Base
    Figured out with you guys help. Turns out the first humming sound is the Vehicle Proximity Notification System, and the brake clunk is something auto pressure the brake system. Thanks you all!
     
  6. Grit

    Grit Senior Member

    Joined:
    Aug 22, 2017
    6,103
    4,032
    1
    Location:
    Wilkes Land
    Vehicle:
    2012 Prius
    Model:
    Four
    It’s the awful sound of a spaceship, I do really want to rip that thing out or replace it with the dukes of hazard chase theme song when they’re fleeing a scene. But I’d be in one hellva slow chase, get caught in seconds haha.