Faint clunking noise coming from 07 Prius when not moving

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by shumiron, Feb 7, 2023.

  1. shumiron

    shumiron Junior Member

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    When I am in the car parked with the car off I can hear a repeating faint clunking sound that lasts for a few seconds then repeats at intervals of a couple minutes or so. This goes on constantly and does not matter if the key is with me or not. I just replaced the inverter coolant pump and all seems good with the car.

    Car info - Base model without keyless entry
    - 211,000 miles
    - Runs excellent but low MPG. less than 40 MPG
     
    #1 shumiron, Feb 7, 2023
    Tombukt2 likes this.
  2. Tombukt2

    Tombukt2 Senior Member

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    I had a front caliper not releasing causing loss of about 4 mpg.
     
    #2 Tombukt2, Feb 7, 2023
  3. Tombukt2

    Tombukt2 Senior Member

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    Check you're rear brakes no leaks etc.
     
    #3 Tombukt2, Feb 7, 2023
  4. bisco

    bisco cookie crumbler

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    is it under the hood?
     
    #4 bisco, Feb 7, 2023
  5. SFO

    SFO Senior Member

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    Could this be the brake accumulator going out?

    What does the 12v battery measure at the jump points under the hood?
     
    #5 SFO, Feb 8, 2023
  6. mr_guy_mann

    mr_guy_mann Senior Member

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    If the sound seems to come from under the rear of the car, that might be the leak detection pump running a test on the EVAPorative emissions system.

    Posted via the PriusChat mobile app.
     
    #6 mr_guy_mann, Feb 8, 2023
  7. shumiron

    shumiron Junior Member

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    Hello everyone. I have listened more carefully and I believe the noise is coming from the High Voltage battery area. I did a 12 V battery check on the display panel and it reads 11.6 volts with car in accessory mode and 14.1 V when Ready.
     
    #7 shumiron, Feb 8, 2023
  8. bisco

    bisco cookie crumbler

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    that's a bit low
     
    #8 bisco, Feb 8, 2023
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