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I can't hear my HV battery fan...Should I worry?

Discussion in 'Gen 3 Prius Main Forum' started by Glen England, Oct 1, 2019.

  1. Glen England

    Glen England Junior Member

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    I've never "heard" the fan sound of my HV battery fan.

    I've only had this 2015 about 2 months so I'm still getting used to it.

    We've had some hot days and some not so hot days. Today set a record. 93. Not since 1952. Anyway, my MPG has dipped the last couple of days but it has been super hot out.

    So, today after driving 16 miles home in 92 degree heat with the A/C on the whole trip I was sure I'd be able to hear the fan.
    I did have the car "off" for about 5 minutes before I remembered to turn it back "on" to listen at the rear vent.

    I was not able to hear anything or feel a suction.
    I have no codes or warnings.

    If the fan wasn't running or there was a temperature problem (which there would almost have to be if the fan wasn't running??) wouldn't that throw a code or error?

    Do I need to be worried?
     
  2. sillylilwabbit

    sillylilwabbit Active Member

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    A/C drops your mileage.

    If you could hear the fan, then there is probably a problem.

    Since you have the A/C on and the battery is in the same cabin as you , the A/C is keeping your battery temperature cool enough.


    iPhone ?
     
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  3. bisco

    bisco cookie crumbler

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    generally, not hearing the fan is a good thing. you would get dash lights it weren't working or the battery overheated. no worries.
    the fan is usually running on a lower speed. try a tissue against the intake grille.

    how many miles on her?
     
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  4. Glen England

    Glen England Junior Member

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    41,000
     
  5. Glen England

    Glen England Junior Member

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    Yes
     
  6. Mendel Leisk

    Mendel Leisk Senior Member

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    I've never heard the fan on our 2010. For a good while I had ScanGuage installed, and monitored the fan speed, saw it up as high as 4 (out of 6 speeds, if I'm not mistaken), but yeah: didn't near it.

    My hearing's not perfect (my wife can go into more detail...), but it's not bad.

    I have cleaned the fan a couple of times too, it was just a little dusty.
     
  7. bisco

    bisco cookie crumbler

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    sounds like you're in good shape. if you want to, you can follow an internet video to clean the fan, and/or, get a scanner that shows fan operation
     
  8. Leadfoot J. McCoalroller

    Leadfoot J. McCoalroller Senior Member

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    A qualified audiologist may be of help.
     
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  9. Eddie25

    Eddie25 Active Member

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    I would get the Hybrid Assistant app and a bluetooth dongle, then you can monitor what speed the fan is at and also turn the fan to high just to make sure it's working. It should be very obvious on high. I hear my fan pretty often even on 3 and 4 (out of 6), but I think my battery may be wearing out because it seems like it stays hotter than most peoples.
     
  10. Grit

    Grit Senior Member

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    The no cost way to figure out if the fan works is to turn on the car, blast the heater in the direct sun for 15 mins. Place ear next to air intake grill.
     
  11. CR94

    CR94 Senior Member

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    If I lean back toward the intake immediately after shutdown on a warm day, I can hear that fan coasting to stop. Otherwise, I generally can not.
     
  12. Montgomery

    Montgomery Senior Member

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    At 44k, I have heard my fan off and on. But usually its very quiet. I wouldn't worry about it. If its running, its keeping the tight area that the battery is located at its proper temperature. Once, last year when we had 5 straight days of 115 degrees and 90 percent humidity (yes, we get humidity here) I heard my fan a lot.
     
  13. Sal43

    Sal43 Member

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    Most of the time my battery fan is too quiet to hear. I do hear it when it's at or near it's maximum setting from time to time.
     
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  14. Daryl K

    Daryl K Member

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    Go figure. Mine is too loud and runs excessively (2012). Even on cool (40 degrees F) early mornings on my work commute it'll be quiet for the first 10-15 minutes after start up, then it starts blasting and maintains near hurricane speeds the entire rest of my commute. Annoying as hell because it sounds like the rear window is partially open.

    I have just over 98k miles and I know the hybrid components warranty runs out at 100k, so I actually have an appointment tomorrow (as I write this) to have them thoroughly review, test and examine the traction battery and associated parts.
     
  15. bisco

    bisco cookie crumbler

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    hopefully, it's just dirty
     
  16. ASRDogman

    ASRDogman Senior Member

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    I've never heard the fan on mine. Maybe because I am always listening to Podcasts.
    It must I've working correctly because I've never had a problem.
     
  17. Bay Stater

    Bay Stater Senior Member

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    Never heard mine either. Must be awfully quiet. :whistle:
     
  18. Glen England

    Glen England Junior Member

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    Thanks so much for the input.

    I’ll not worry.

    I’ll trust that the car is smart enough to tell me if something is wrong.


    iPhone ?
     
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  19. cww

    cww Junior Member

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    Does the fan sound loud?
     
  20. BZzap!

    BZzap! Senior Member

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    Typically the fan is virtually silent. When you are able to hear it is when things are not right. It’s just like your HVAC blower. When it gets overly loud, chances are, you have debris struck in the fan cage causing imbalance and vibration.