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2010 Prius IV - Hot AC when Engine Runs

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by JoeMartin, Mar 12, 2020.

  1. JoeMartin

    JoeMartin New Member

    Joined:
    Mar 12, 2020
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    Location:
    Pensacola
    Vehicle:
    2010 Prius
    Model:
    IV
    Hey guys!

    Recently bought a 2010 Prius IV with 132k on the clock and it runs beautifully.
    When I got in it I noticed the AC was nice and cold and didn't think too much on it.
    Purchased it and drove away.

    Shortly after, however, I noticed that whenever the engine ran the AC would no longer blow cold.
    Checked it at idle with engine off, and AC gets down to ~40 degrees, but gets up to over 90 with the engine running and changes over to hot almost immediately once the engine runs.

    I checked the codes on the AC itself and it has error code 23, but I don't believe the sensor is malfunctioning. The compressor is running when the engine is either on or off.

    I was thinking maybe a blend door issue, but not too sure on that one.

    As soon as the engine turns off the AC starts to get cold again.

    I noticed that part 063800-1100 (Factory AC Heater Servo Regulator) does not move at all.
    Like... Can't even move the gears attached to it by hand. Super stuck.
    Would that cause this issue?

    Thanks for the help in advance.
     
  2. JoeMartin

    JoeMartin New Member

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    Location:
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    Vehicle:
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    Model:
    IV
    Any ideas on this one?
     
  3. JoeMartin

    JoeMartin New Member

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    Model:
    IV
    Figure I'll update this for whomever else has this issue.
    Issue was that the part mentioned would not move the blend door.
    The servo was completely seized. I have manually moved the blend door and it temporarily resolves the issue.
    I am buying a new servo and will report back.
     
    Grit likes this.
  4. JoeMartin

    JoeMartin New Member

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    Location:
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    Vehicle:
    2010 Prius
    Model:
    IV
    Verified replacing the servo fixed the issue. It was caused by the servo seizing up and not moving the blend door.
     
  5. FrankB

    FrankB Member

    Joined:
    Dec 12, 2012
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    Vehicle:
    2010 Prius
    Model:
    II
    Have you checked the EGR cooler on your new Prius? It's got about the right mileage to be overdue for a cleaning.
     
    pjksr02 likes this.
  6. John in AZ

    John in AZ Junior Member

    Joined:
    Aug 21, 2013
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    Vehicle:
    2007 Prius
    Model:
    ----USA----
    Where is this located? I have same problem but not sure how to get to the blend door servo.
    Thanks
     
  7. ChapmanF

    ChapmanF Senior Member

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    Location:
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    Vehicle:
    2010 Prius
    Model:
    IV
    John, this is a thread about Gen 3, but are you asking about a 2007 like your profile says? The HVAC systems are different. Check this post here, which shows all three servos on a Gen 2.

    Be sure you know which servo you need to look at, and avoid the mistake of calling all three of them the "blend door" (I don't know why, but a lot of people do that). There's only one of those, for blending the warmed and unwarmed air to get the temperature you want. The other two select the air inlet (fresh or recirculated) and the air outlet (feet, dash, or defog).