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Massive amount of water in battery tray and spare tire well

Discussion in 'Gen 2 Prius Main Forum' started by jburg, Oct 12, 2020.

  1. jburg

    jburg Member

    Joined:
    Jan 27, 2020
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    Location:
    RTP, NC
    Vehicle:
    2010 Prius
    Model:
    One
    Well, my buddy's wife had an issue with his '06 Prius this morning and I went to his wife's job to check everything out.

    Was throwing a P3190 code and I decided to take everything on the induction system apart clean the MAF, check all the connections, etc. I had him take the back panels apart to unplug the battery reset the ECU and there was a massive amount of water in the spare tire wheel well. Drained the water, and buttoned everything up and took her for a test drive and we still heard water sloshing around in the trunk. Park the vehicle and take a look and what we didn't notice was that the battery was 3/4 covered in water.

    The car was running well again and we drove it about 10 miles back to my place to take a look at everything. We drained all of the water out of the battery compartment (had to be close to a gallon of water) and took apart the entire rear passenger taillight assembly and the top bolt on the light was only just hand tight (culprit?). I cleaned all the surfaces, and put the light back together and performed a leak test and everything looked good, but I was hearing a slight drip. So I really started looking really well. Turns out there was a pretty good leak coming from a metal vent that was about of foot or so right from the middle of the latch and it was definitely coming from under the bumper.

    So, we got to drop the bumper.

    Turns out there is a metal seam that is just under the tail lights on both sides of the car that is held together with a few spot welds. The piece that comes from the bottom of the car, lays on top of the piece that is under the taillight and is just tacked on.

    Interesting enough, this seam is not covered with any seam sealer. I applied some silicone, got lunch and ate it in my drive way, and then tested the seal with some water - GTG. If anyone is looking for a leak in there trunk hatch area, this may be the source. I would suggest getting some actual Auto Seam Sealer Caulk for the job.

    What sucks is that you can only seal the outside as the inside of the seam is hidden under more sheet metal

    I should have taken pictures, but I was working on the car nearly 5 hours (and I had help) at this point and I was just wanting to get it done.
     
  2. edthefox5

    edthefox5 Senior Member

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    Location:
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    Vehicle:
    2007 Prius
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    Two
    Just about everybody has a the hatch leak. It comes from the roof. Take the black plastic covers on the sides of the roof off they pop right off at the back end where they meet the hatch valley valley corner on the passenger side you will lots of little cracks in that valley runing up the valley the black plastic covers. That's where all the water in the battery well is coming from. Really common in the bottom of the battery well there is a rubber plug either drill a small hole in the plug or pull it.

    Prius are plagued with mice damage they like chewing on the wires so if it lives outside don't remove the plug drill a hole in it and drill a small hole in the plug under the spare tire.

    Also the water on the top passenger side roof leak tends to drip on the hybrid battery vent fan motor and rots it out.
     
  3. jburg

    jburg Member

    Joined:
    Jan 27, 2020
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    Location:
    RTP, NC
    Vehicle:
    2010 Prius
    Model:
    One
    Thanks for the suggestion. We checked all the usual spots with water and it seemed to only be coming from the area that we identified, but I will let him know to keep his eyes peeled.
     
    Raytheeagle likes this.
  4. ski.dive

    ski.dive Active Member

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    Location:
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    video of leak repair

     
  5. Moses Bruh

    Moses Bruh Member

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    Location:
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    Vehicle:
    2008 Prius
    Model:
    Four
    There are many area the leaks come from, I recommend removing all the covers to expose the bare metal and have someone spray water over the car while someone inside looks for the area of the leak. I had a leak coming from the screw hole of the tail light and had to seal that up. Some people have hair line cracks on the metal around the hatch struts and etc. Best way is to just had water running and look for the leak.
     
    Brother A likes this.