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Slow thudding noise behind the dash when stopped

Discussion in 'Gen 2 Prius Technical Discussion' started by Banksy, Aug 27, 2020.

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  1. Banksy

    Banksy Active Member

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    When I stop my car I hear this slow thudding noise.

    Is this the abs actuator? I thought that was a fast rattle snake kind of sound.

    I only heard it when stopped. Sounds like it's coming from near the middle of the dash.


    Very slow thudding sound.


    Any idea of what it is?
     
  2. bisco

    bisco cookie crumbler

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    possible, or hvac vent
     
  3. Banksy

    Banksy Active Member

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    Hvac vent?

    I have the bottom glove box off however I don't hear it from there where the blower motor is
     
  4. bisco

    bisco cookie crumbler

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    there are vent doors behind the dash that open and close to change air direction. sometimes they get stuck and make a kind of thumping sound. the brakes are a honking sound. does it only happen with foot on brake?
    can you post a recording?
     
  5. Banksy

    Banksy Active Member

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    I can't get an accurate recording

    Sounds like it's coming from near the vent with the park button on it right near the nav screen

    Also happens when parked not foot on brake doesnt matter.
     
  6. bisco

    bisco cookie crumbler

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    is it possible that it is happening while driving, but too quiet to hear?
     
  7. Banksy

    Banksy Active Member

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    No I can't hear it while driving

    I can hear the fast clicking of what I assume is the ABS actuator. Which shuts off after a second or two but I can only hear the slow thudding at a stop

    I could be wrong though but I haven't noticed it while driving
     
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  8. ChapmanF

    ChapmanF Senior Member

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    Recordings are super helpful in such situations.

    Here was one that turned out to be the guy's coolant control valve.

    [​IMG]
     
  9. Banksy

    Banksy Active Member

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    I will try to get a recording tomorrow
     
  10. ChapmanF

    ChapmanF Senior Member

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    Does that one sound at all like yours?
     
  11. Banksy

    Banksy Active Member

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    Can't open the file on my phone
     
  12. ChapmanF

    ChapmanF Senior Member

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    Yeah, I think PriusChat wouldn't allow it uploaded without being zipped first. Has to be unzipped, then should play.
     
  13. Banksy

    Banksy Active Member

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    Can you email it to me?
     
  14. fotomoto

    fotomoto Senior Member

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  15. Banksy

    Banksy Active Member

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    So on further investigation it seems this does happen when both driving and still.

    Thudding seems to be at a constant pace then will sometimes get faster.

    Also does not do this when only in accessory mode

    do not know if it's me but when turning the wheel that seems to be the case.

    I have a recording of this however the website won't allow me to post it
     
    #15 Banksy, Sep 7, 2020
    Last edited: Sep 7, 2020
  16. sam spade 2

    sam spade 2 Senior Member

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    Well you have TWO good suggestions already......and you seem to be ignoring both of them.
    Let me add a third one: Something stuck in the blower fan.

    IF......you can't manage to find this sound, how do you figure to FIX it when it is found ?
    Take it to the shop.
     
  17. ChapmanF

    ChapmanF Senior Member

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    What format is the recording? Can you zip it and upload the zip file? PriusChat allows zip files.
     
  18. Banksy

    Banksy Active Member

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  19. Banksy

    Banksy Active Member

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    IF......you can't manage to find this sound, how do you figure to FIX it when it is found ?
    Take it to the shop.[/QUOTE]


    Never


    Posted this a while ago didn't recall the suggestions you're mentioning.

    Also I'm sure if I took the dash panels off I could find it pretty quick. Would rather not do that yet.


    Assumed this has probably happened before on here.


    Which blower are you referring to? The one behind the glove box? Because if that's what you're talking about it's 100% not coming from there.