2020 Rear Defogger?

Discussion in 'Gen 4 Prius Main Forum' started by priusmatty, Feb 15, 2021.

  1. priusmatty

    priusmatty Member

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    Louisiana here. We got some very rare snow and ice. So I turned on the rear defogger/defroster, and after 20+ minutes, nothing happened. Nothing was melted at all. Is it broken?
     
  2. ChapmanF

    ChapmanF Senior Member

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    Doesn't sound right. If you know anybody with a thermal imager, it can answer that question in seconds.

    Sometimes a piece of wayward cargo can scrape through some of the defogger pattern on the window, but that usually only leads to one or two lines that aren't heating (and can be fixed with some conductive paint).

    If none of it is heating at all, that sounds like maybe it isn't getting power at all. You could see if anything different happens if you use Techstream to turn it on.
     
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  3. robsnyder20

    robsnyder20 Active Member

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    In my last car, the person who did the tint cut thru a few of my lines on my defogger, just a thought. Can always check the fuse but you shouldn't see a light if its a fuse issue too
     
  4. priusmatty

    priusmatty Member

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    I will check. Actually, it is a brand new car under warranty. I'll make the damn dealer check it lol
     
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  5. alanclarkeau

    alanclarkeau Senior Member

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    Is the external mirror defogger working?
     
  6. priusmatty

    priusmatty Member

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    Not sure, because there was no ice or snow on the side mirrors.
     
  7. alanclarkeau

    alanclarkeau Senior Member

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    You should still be able to see if the mirrors are warm after being on for a while. Also - with the rear window, it turns off after, I think 10 or 15 minutes - so after 20 mins it would be cold again. (Not here - it's blazing sunshine.)
     
  8. The Professor

    The Professor Senior Member

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    Just throwing it out there, but it is an interior demister/defogger, not an external deicer/desnower. You remove the ice and snow on the outside manually, then let the car clear the steamed up windows on the inside.

    That's not to say snow and ice might not melt enough to slide off after a while, but it doesn't always.

    SM-T813 ?
     
  9. jerrymildred

    jerrymildred Senior Member

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    That's a good point. The one on my Prime won't even remove dew from the back window much less frost. It just kind of clears the surface right at the grid.
     
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  10. ChapmanF

    ChapmanF Senior Member

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    Huh. Mine of course doesn't make ice or snow cover disappear (on any reasonable time scale), but will definitely get stuff loose enough to shove right off the back window with my scraper, where otherwise I might be stuck back there chipping away at it.
     
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  11. priusmatty

    priusmatty Member

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    took to dealer, they said it is working right.
     
  12. alanclarkeau

    alanclarkeau Senior Member

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    did you check if the mirrors are getting warm?
     
  13. priusmatty

    priusmatty Member

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    Yes, they made me feel the wires, and I could feel warmth.
     
  14. Tande

    Tande Active Member

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    Same here.......
     
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