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Intermittent whining noise while A/C is on

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by h13roglyphix, Apr 13, 2021.

  1. h13roglyphix

    h13roglyphix Junior Member

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    Hi all,
    first time posting on here, hope I'm doing this right.
    I have a 2013 Prius 3 with 105k miles. I recently took it out of town on a road trip and came home with what I think is a new sound. There is a sort of whining or "winding up" sound that seems to be related to the air conditioner. When the A/C is running, I get the whining sound that starts up and stops repeatedly. It's only audible when the car is parked and the ICE isn't running and the fan is at low speeds. The sound has no affect on the temperature or pressure of the air coming out of the vents. Both seem to be working as well as they did when I bought the car (I've had it for about 2 years and put 12,000 miles on it). When I turn the A/C off and on, the buttons on the dash seem to "complain" like they have some sort of electrical issue, if that makes any sense. There is a higher pitched whirring sound that comes from the center counsel. I was wondering if anyone has had similar issues or any ideas if I should be concerned? The A/C ran smoothly and quietly before I left...
    Thanks
     
  2. AW82

    AW82 Member

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    2012 Prius
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    Two
    The whining noise in my car tends to relate more to whether my kids are with me.

    But...it seems the first question with things like this is "how old is the 12v battery?" Have you ever replaced it?
    Also, when you say "turn the A/C off and on" are you literally pushing the A/C button, or turning the whole system on and off? In other words, have you tested with the A/C off but the fan running? And what about switching the vent (that is, switch from blow-in-face to blow-on-feet, etc.)? I'm new to Prius, but on past cars, whining from the center console often means the blend door is sticking or the actuator is going bad. Isolating this by testing with the A/C off but the fan running and switching where the air is blowing will give you more clues.
     
  3. Grit

    Grit Senior Member

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    like “stop pressing me” or “I won’t get any colder no matter how much you keep pressing” ?
     
  4. h13roglyphix

    h13roglyphix Junior Member

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    Location:
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    Vehicle:
    2013 Prius
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    Three
    I changed the 12 volt battery about 6 or 7 months ago, so I don't think it's that. Good question about the A/C buttons! I investigated a bit more today and the whining noise is only present when the A/C is on, but when I switch to only the fan it goes away. But when I push the buttons to switch between the A/C or the fan, then I get the second noise that sounds like the dash complaining... more like a "stop pressing me" sound lol. It's like an electrical buzzing sound- a buzz followed by three quicker buzzes each time ( I forgot to check switching the vent directions, will do next). After driving it around on errands today, I also noticed that both the buzzing and the whining sound only happen after the ICE has started up for the first time. I was parked and started the car and fiddled with the A/C for a bit while it was in ready mode and before the first time the engine cycled up and had none of these issues or sounds. Either way, the A/C still seems plenty cold though!

    I'll look into the blend door and actuator stuff to see what I can learn-- I'm also wondering, since the sounds only seem to crop up after ICE has started, could it be related to the engine or battery in some way too? It's had a bit of a rough idle since I've been back as well and the engine seems a bit louder. I got it an oil change and since it's at over 100k I'm figuring it needs new spark plugs soon too...
     
    #4 h13roglyphix, Apr 17, 2021
    Last edited: Apr 17, 2021
  5. bisco

    bisco cookie crumbler

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    egr circuit needs cleaning, but probably not related to the buzz