Gen 2 Prius Strange repetitive noise from a/c - heater unit

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Theodore, Sep 2, 2025 at 1:22 PM.

  1. Theodore

    Theodore Junior Member

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    Hi to all !
    I have the Prius Gen 2 , 2009 year and I am listening a strange repetitive noise, like "tak","tak" in in the middle of the dashboard and I believe, It's coming from the a/c-heater unit. Like a dumper which can not find it's position and goes on.
    I would like to point out, this noise goes on, even the clima unit is off.
    It stops only, when the car is off.
    What can I check first?
    I have experience to technical issues , as I am electronic engineer.
     
    #1 Theodore, Sep 2, 2025 at 1:22 PM
  2. bisco

    bisco cookie crumbler

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    it does sound like a vent door that can't decide which position to stop at. i would start with a search. you might find that someone else has already done the legwork.
    if not, the service manual should cover it.
     
    #2 bisco, Sep 2, 2025 at 1:35 PM
  3. Tombukt2

    Tombukt2 Senior Member

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    The two motors right by you're gas pedal foot attached to air box black square things put you're hand on to find the unit hunting . Remove look inside you'll see what to do it's indexed mark the wheel etc .
     
    #3 Tombukt2, Sep 2, 2025 at 1:48 PM
  4. ChapmanF

    ChapmanF Senior Member

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    #4 ChapmanF, Sep 2, 2025 at 3:19 PM
  5. PriusCamper

    PriusCamper Senior Member

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    Are you certain its not coming from the engine compartment?
     
    #5 PriusCamper, Sep 2, 2025 at 4:40 PM
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