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Strange muffled click sound seemingly from rear center when transitioning between electric and gas

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Issaction, Jun 19, 2019.

  1. Issaction

    Issaction New Member

    Joined:
    Mar 20, 2019
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    Location:
    Salt Lake City
    Vehicle:
    2010 Prius
    Model:
    Five
    Hey guys. Relatively new owner (3 months) of a 2010 Prius Trim 5 w/solar and loving it for the most part. This post will have a lot of info in it to help narrow things down and I would very much appreciate if someone could offer some guidance.

    Mileage: 147,000
    Hybrid Battery: Original (69% condition according to Dr. Prius App and holding a charge similar to a 30,000 mile Gen 3 Prius I regularly drove in the past)
    Battery Fan: Recently cleaned
    Front and rear seats: Secured into place properly
    12V Battery: Tested and working properly. Under 6 months old.
    Transmission and Engine: Original
    Oil changes: Consistent and under 5K miles. Full Synthetic.
    Under the hood fluids: At proper levels and good condition.

    Here's the issue:

    When I come to a complete stop somewhere, the gas engine naturally shuts off. When I eventually start to accelerate, at the exact point on the monitor when I transition from the first bar (EV) to the second bar (ECO) and thus the engine kicks on to provide more power to the wheels, I hear a faint but audible singular click coming from what sounds like the center of my vehicle slightly behind me (from the driver position). This happens every single time, and doesn't seem to affect anything else. It has happened for the past 7K miles (Since I purchased the vehicle), and has not gone away.

    The only thing I can think of it sounding like is when you click the top of a large plastic storage container together, but quieter and more muffled (as it doesn't seem to be coming from the interior of the vehicle.) A storage bin that looks like this: [​IMG]

    I hope you understand what I mean by this sound.

    This is the only noticeable symptom. The car still shifts fine between reverse, neutral, drive, and B. It doesn't slip or anything like that, and it has an adequate amount of power. There is no sort of grinding, or noticeable extra hesitation when the engine kicks in.

    Any ideas as to what this is?
     
  2. bisco

    bisco cookie crumbler

    Joined:
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    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    at any particular speed? i'm thinking auto door locks
     
  3. Issaction

    Issaction New Member

    Joined:
    Mar 20, 2019
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    Location:
    Salt Lake City
    Vehicle:
    2010 Prius
    Model:
    Five
    I appreciate your reply.

    It is not the door locks. It is at a specific point when electric transitions to gas on the display. Not even at a specific speed. Related in some way to the drivetrain I think.
     
    bisco likes this.
  4. Grit

    Grit Senior Member

    Joined:
    Aug 22, 2017
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    Location:
    Wilkes Land
    Vehicle:
    2012 Prius
    Model:
    Four
    The relay in the hv bat assembly clicking to engage hv bat circuitry to discharge & propel vehicle?
     
  5. Issaction

    Issaction New Member

    Joined:
    Mar 20, 2019
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    Location:
    Salt Lake City
    Vehicle:
    2010 Prius
    Model:
    Five
    This is definitely possible. Thanks for the reply.

    Is those a common point of failure? Is it actually doing any harm, or just a slight annoyance? Is it difficult to fix?
     
  6. ChapmanF

    ChapmanF Senior Member

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    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV
    The system main relays would sound like they are behind you (just behind the rear seat, on the passenger side), but they don't change state while driving. They are energized when you first push the power button to READY (you should hear three clicks in rapid succession) and they don't click again until you use the button to power off.

    So whatever this click is won't be those.
     
  7. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
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    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    Have someone sit in the rear seat, try to pinpoint it. Or switch it up: have someone else drive, and you do the close-up listening. Maybe flip down the larger side of the rear seatback too.