Electric motor whirring when car is parked

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Wittyfull, Dec 11, 2013.

  1. Wittyfull

    Wittyfull Junior Member

    Joined:
    May 24, 2008
    15
    1
    0
    Location:
    Houston
    Vehicle:
    2012 Prius
    Model:
    III
    Hi all,

    I ventured into the garage late last night and heard a whirring noise like an electric motor coming from my Prius. I didn't have my smart key with me. I checked the doors to see if any were ajar. The whirring kept going. After a few minutes, it stopped.

    Does anyone know what the car is doing? I have a 2012 Prius Three with 18K miles on it.

    Thanks,
    David
     
    #1 Wittyfull, Dec 11, 2013
  2. frodoz737

    frodoz737 Top Wrench

    Joined:
    Aug 26, 2010
    4,415
    2,387
    33
    Location:
    Texas
    Vehicle:
    2015 Prius
    Model:
    Four
    I'm sure somebody here has the definitive answer for you, but I gave up trying to figure out what all the new sounds were real fast.
     
    #2 frodoz737, Dec 11, 2013
  3. Air_Boss

    Air_Boss Senior Member

    Joined:
    Jun 2, 2012
    4,089
    1,129
    0
    Location:
    New Yawk
    Vehicle:
    2012 Prius v wagon
    Model:
    Five
    Battery fan? The key issue is it stopped (or cycled).

    FWIW, the electric radiator fan on the roadster does same by design, after a thrashing.
     
    #3 Air_Boss, Dec 11, 2013
  4. fuzzy1

    fuzzy1 Senior Member

    Joined:
    Feb 26, 2009
    17,558
    10,331
    90
    Location:
    Western Washington
    Vehicle:
    Other Hybrid
    Model:
    N/A
    It appears you have a Liftback, not a 'v'. If so, you posted to the wrong forum, but then I also have the same car as you, so any different function of the 'v' doesn't apply.

    About five hours after the last trip, the evaporative emission control system fires up a fan for a few minutes. It is normal. Somewhere in the manual is a list of this and numerous other unfamiliar sounds you may hear.
     
    #4 fuzzy1, Dec 11, 2013
  5. xliderider

    xliderider Senior Member

    Joined:
    Apr 19, 2012
    8,002
    3,192
    0
    Location:
    Honolulu, HI
    Vehicle:
    2011 Prius
    Model:
    Three
    A common whirring sound is the brake booster, the one that also comes on everytime the driver's door is opened. It also happens a few minutes after the car is shut down.

    It usually lasts only a few seconds though.

    SCH-I535
     
    #5 xliderider, Dec 11, 2013
  6. Wittyfull

    Wittyfull Junior Member

    Joined:
    May 24, 2008
    15
    1
    0
    Location:
    Houston
    Vehicle:
    2012 Prius
    Model:
    III
    Whoops, I have a standard Prius, not a v, but the innards are basically the same. The whirring sound was happening after the car had been sitting for over 6 hours in my garage. The temperature was in the 40s F in the garage. It sounded like it was coming from the rear of the vehicle.

    Does main battery charge up the 12V (standard) battery if it is low? That was the cause of the Tesla vampire draw issues.
     
    #6 Wittyfull, Dec 11, 2013
  7. fuzzy1

    fuzzy1 Senior Member

    Joined:
    Feb 26, 2009
    17,558
    10,331
    90
    Location:
    Western Washington
    Vehicle:
    Other Hybrid
    Model:
    N/A
    No. For safety to mechanics and emergency responders, the main battery is disconnected by a relay inside its own case whenever the ignition is turned off. If the 12V then falls too low, it must be jumped from outside, or replaced, before the main battery relay can be switched back on.
     
    #7 fuzzy1, Dec 11, 2013
  8. Paradox

    Paradox Prius Enthusiast / Moderator
    Staff Member

    Joined:
    Sep 22, 2005
    29,110
    8,591
    201
    Location:
    USA
    Vehicle:
    2014 Prius v wagon
    Model:
    Five

    This is explained in the manual but here's the basics from it: "Approximately five hours after the hybrid system is turned off, you may hear sound coming from under the vehicle for several minutes. This is the sound of a fuel evaporation leakage check and, it does not indicate a malfunction."

    Also, thread moved to the gen III forums.
     
    #8 Paradox, Dec 11, 2013
  9. Grren4ever

    Grren4ever Active Member

    Joined:
    Sep 29, 2013
    347
    167
    19
    Location:
    Canada
    Vehicle:
    2013 Prius
    I heard this same whirring noise a long time after the car was stopped too. Glad someone has an explaination for this. In another unrelated post, I actually walked into the garage this week and noticed the interior map lights turning off on after being about 2 meters away from the car. I opened the door and made sure I didn't accidentally have them switched on somehow...after tripping checking, I shut the door and they dimmed and turned off...weird! it's like the car was welcoming me.

    And no, I did't have the smart key with me too.
     
    #9 Grren4ever, Dec 12, 2013
  10. Wittyfull

    Wittyfull Junior Member

    Joined:
    May 24, 2008
    15
    1
    0
    Location:
    Houston
    Vehicle:
    2012 Prius
    Model:
    III
    Great. Thanks for all the help.
     
    #10 Wittyfull, Dec 12, 2013
(You must log in or sign up to post here.)