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front defogger didn't work

Discussion in 'Gen 3 Prius Technical Discussion' started by JudithZ, Dec 15, 2010.

  1. JudithZ

    JudithZ Junior Member

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    I'm a new Prius owner (only 500 miles) and have experienced a lot of issues so far. Today I got in my car and both front and rear windows were fogged up. I turned on both defoggers and the front window would not clear. I set the vent speed to high and could hear a noise like the air was blowoing, but it did NOT clear the front window - I had to clear it with a cloth so I could see. Has anyone else experienced this and know what might cause this?
     
  2. mainerinexile

    mainerinexile No longer in exile!

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    It sounds like you turned up the fan speed, but did you set the air to blow onto the windshield (defrost mode)?
     
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  3. JudithZ

    JudithZ Junior Member

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    I pushed the Front defogger button. It's worked a few times before. Is there some other button I have to use?
     
  4. Troyroy

    Troyroy Member

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    It's hard to tell just what is going on. But....if you pushed the "front defroster" button. I don't think the fan will blow air until the ICE has warmed up.
     
  5. mainerinexile

    mainerinexile No longer in exile!

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    It WILL blow before the ICE warms up, and indeed it will blow A/C air automatically which is what you need for defrosting--dry air.
     
  6. john1701a

    john1701a Prius Guru

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    I get the impression you had the RECIRCULATE button pressed.

    If so, moisture will just continue to get worse. Outside air is required for drying. Make sure that inside-only mode is not activated.
    .
     
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  7. qbee42

    qbee42 My other car is a boat

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    Next time switch your climate control to A/C Auto. That will avoid making manual configuration errors. After that, press the defrost button as needed.

    Tom
     
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  8. Former Member 68813

    Former Member 68813 Senior Member

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    The front defogger uses AC and engine heat to effectively defog. If you start in cold weather there will be not enough heat to evaporate a lot of moisture. I had that happening too and had to wipe the windshield. Not a huge deal if you ask me.
     
  9. JudithZ

    JudithZ Junior Member

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    thanks to everyone who offered tips on this.

    I'll try your suggestions and post back what the results are.

    to Friendy Jacek: it actually is a big deal. I expect things to work in a new car, and since it's a Toyota I expect things to work for a very long time -:) This isn't the only problem I've had since I got the car - possibly it's a matter of learning exactly how to set these controls.
     
  10. theMisFitCrazy8

    theMisFitCrazy8 New Member

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    I agree if you buy a new car it should work properly
     
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  11. Codyroo

    Codyroo Senior Member

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    Judith,

    Next time you turn on the front defogger, look to see if the A/C button is illuminating. If it isn't, that would explain the issue you are seeing (turn it on, if it isn't on when you press the front defogger button).

    I don't recall if the A/C comes on automatically (it may) when you press the front defogger, I'll check that tonight when I drive home.
     
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  12. Troyroy

    Troyroy Member

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    When you push the Front defogger button, the mode automatically switches and the AC comes on, but the AC button light does not light up. Plus you can not switch the air source to recycle the interior air.
     
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  13. donee

    donee New Member

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    Hi JudithZ,

    Welcome to Prius Chat!

    To defog the window, the defroster needs outside air. Even warm air, if its moist, will make the window fogged over.

    On the passenger side of the cowl (just below the windshield) there is a 15 inch row of vents. These vents must be cleared of snow for the system to get outside air. After clearing snow from on top of the vents, take the snow brush and brissle down hammer into the metal grill. This will force the snow through the grill, where it will fall to the bottom of the enclosure, opening up the path from the grill to the air intake.
     
  14. bisco

    bisco cookie crumbler

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    there is a great section in the owners manual regarding heating, ventilating and air conditioning. although somewhat technical, after reading thrugh a few times, even i, a non techie was then able to operate the controls efficiently. all the best!:)
     
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  15. JudithZ

    JudithZ Junior Member

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    thanks Donee but there's no snow here (I'm in northern California, near SF). but will keep this in mind if I ever drive cross country in the winter :)
     
  16. JudithZ

    JudithZ Junior Member

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    yeah I'm trying to find the manual online where it's easier to read -:)
     
  17. Mendel Leisk

    Mendel Leisk EGR Fanatic

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    There's something in the Owner's Manual on the subject, saying to raise the temperature if the windshield is not clearing.
     
  18. Former Member 68813

    Former Member 68813 Senior Member

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    I guess you missed the news last year that Toyota is not a quality leader anymore.

    Let me ask you a question. Did you expect the front windshield "defogger" working with cold engine in your previous car?
     
  19. donee

    donee New Member

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    Hi Judith,

    I was not sure where in California you were. There is even snow in Southern California, btw. We get comments from people about it from Big Bear west of LA on occasion.

    You might want to be more descriptive in your location.
     
  20. dbldbl

    dbldbl Junior Member

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    Thanks. I've been looking for tips as I've been really disappointed (understatement of the year) with Prius heat/defrost mode

    I expect the defrost to defrost - and not take until I make it home from work -or vice versa. I expect it to clear the ENTIRE front windshield and not just 2 tiny 6 x 8 patches where the windshield meets the dash.

    Defrost should AUTOMATICALLY kick in the AC system. Duh. That's how defrost works. Not just heat (unless it's a 1960 something or other.)

    Ya. By the time I get to the next state it's ok. But 1-2 hours is a bit much, guys.

    What's wrong with the engineers? Too much time in So California?