AC Blower on before car is started

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by TheLandYacht, May 22, 2021.

  1. TheLandYacht

    TheLandYacht Member

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    2010 Prius

    Odd thing.

    We went to get in the car & the blower fan was blowing (seemed on low) ambient temperature air thru the car. Couldn't tell if it started when she opened the door or if it was already blowing.

    The FOB was with me, inside the store, so it wasn't reacting to the presence of the FOB.
    ...and the ambient temp inside the car was like 100+ (after sitting in the sun for a while). Which was my thinking, maybe the brain of the Prius says "it's too hot, lets run the fan for a while"?

    Thoughts?
     
  2. fuzzy1

    fuzzy1 Senior Member

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    Does it have a solar sunroof option? If so, it was likely running the Solar Powered Ventilation System.

    There is a lower dash switch to enable or disable it.
     
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  3. TheLandYacht

    TheLandYacht Member

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    Thank you, kind sir/ma'am/other!

    ...still finding out new things about my Prius
     
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  4. sam spade 2

    sam spade 2 Senior Member

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    And if not, a relay might be sticking.

    His response to this suggestion did not really say if you hit the bulls eye or not. :)
     
  5. ChapmanF

    ChapmanF Senior Member

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    I saw the profile said a Three, and I couldn't remember whether the solar vent package was an option for Threes, but according to the 3G equipment thread it was available.

    That's going to stay my guess. In a 2010 without the solar ventilation, there isn't any relay in the blower circuit; the 50 amp supply to the motor is powered at all times, but the motor only runs when the A/C amplifier is sending it pulses telling it to run and how fast.

    So any stuck relay situation would have to be the one that powers the A/C amplifier ... but that would be the IG1 relay, so a bunch of other stuff would be on too, like the dash display.
     
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  6. mikey_t

    mikey_t Active Member

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    I've always been curious about how helpful that feature is. Could you follow up sometime about how much cooler it makes the interior on a hot day?
     
  7. fuzzy1

    fuzzy1 Senior Member

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    I still have the 2010 brochure hardcopy, from my first Prius purchase, so looked it up there. But that thread has much better coverage than my brochure collection.
    I'm figuring that if it had been a stuck relay, the car would most likely have been dead silent and dark with a drained 12V battery.
     
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  8. sam spade 2

    sam spade 2 Senior Member

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    Yea probably right.
    But maybe the relay only becomes "hot" when the car "wakes up".
    :rolleyes::whistle:
    :ROFLMAO:
     
  9. Grit

    Grit Senior Member

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    Trim 3 & 4 has solar roof. I tapped into the solar lead and hooked it up to a LiFePO4 battery bypassing the 10 min turn on relay. The solar panel roof is finally useful now.
     
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  10. ChapmanF

    ChapmanF Senior Member

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    I don't think I can quantify it, but I genuinely like it ... I'd say it makes the interior ... "tolerable" ... where "tolerable" is not something I grew up expecting car interiors to be on hot days.

    I still don't dawdle much before pushing the power button so the A/C can come on. :)
     
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