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Leak source for battery fan wiring loom corrosion?

Discussion in 'Gen 2 Prius Technical Discussion' started by TonyR, Oct 29, 2024.

  1. TonyR

    TonyR Junior Member

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    I posted a while back about fault codes coming up on my otherwise very reliable 2004 Prius and folk pointed to water-leaks corroding the wiring related to the battery cooling fan. I’ve now had some time again to investigate and that is indeed the problem and it’s been repaired. So all good there.

    The question though as this seems to be a standard problem, is where is the water leak coming from. I know from experience that tracing the source of a water leak can be difficult as water runs along things and appears far from the leak site. So for those that have been there, any advice on where to look and how to fix it?

    Thanks
     
  2. mr_guy_mann

    mr_guy_mann Senior Member

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    Use the search feature and look for "tailgate water leak" in the Gen2 forums. The most common problem is cracked seam sealer around the tailgate opening on the body.

    Look around the lift piston mount and up into the rain gutter on the roof under the black rubber strip.

    Quick fix is to clean and dry the affected areas. Reseal with a good caulk. (Automotive seam sealer like 3M # 08505 is more $$ but will last longer)

    Posted via the PriusChat mobile app.
     
    Brian1954 likes this.
  3. Tombukt2

    Tombukt2 Senior Member

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    Quick is to open water pass they plugs in that area . Fix plug of fan zip tape the repair. Move plug over about two inches . It'll never get wet generally again and water passes thru chassis as designed . PDI was done incorrectly as far as I'm concerned . Rubber plugs need be put in strategic places
     
  4. bisco

    bisco cookie crumbler

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    another weak spot is the rain gutter weld underneath the black molding
     
  5. TonyR

    TonyR Junior Member

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    Thanks!
     
  6. TonyR

    TonyR Junior Member

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    Sorry, again in English?
     
  7. mr_guy_mann

    mr_guy_mann Senior Member

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    Translating from "Tom-ish" to English.

    Repair and mitigate the symptoms but don't fix the leak.

    Not my preferred strategy.

    Posted via the PriusChat mobile app.
     
  8. Mendel Leisk

    Mendel Leisk EGR Fanatic

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    Anyone else thinking of the lineup scene in The Usual Suspects? ;)
     
  9. Tombukt2

    Tombukt2 Senior Member

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    Water sposed too be allowed to pass thru chassis by design reason for the plugs in first place.remove them and pass thru occurs as it designed . Now you can strip off stuff to fix the bonding points that failed at ones leisure. Because the liquid won't ruin anything . It's not living in the space it's just passing through as designed generally won't hurt anything.thats all . This is done so you don't have to line dry the chassis suspending it like by the trailer ball or receiver like the laundry.like the doors in monsters once he he. Toyota has made boats before.