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12 volt battery change and alot of water under it

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by khp, Feb 5, 2013.

  1. Corwyn

    Corwyn Energy Curmudgeon

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    I had a similar problem (though mine was ICE!). Thank for the info, I will see if I have a crack as well.
     
  2. PriusCamper

    PriusCamper Senior Member

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    I checked alot of places mentioned on this thread for cracks and didn't see any... So I pulled the plug and let it dry out and then put the plug back in from the opposite side on the outside... I thought this would make it easier to determine if more water was getting in later. But after all that effort cleaning and searching for cracks my car is no longer leaking. I never found the leak and the car has taken nearly 30 inches of rain since then and everything is still dry.

    The water in my battery compartment smelled like really old water too. So I suspect the source of my leak was related to a seal that possibly didn't sit right and it may possibly happened years before I owned the vehicle.
     
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  3. khp

    khp Member

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    I had a heck of a time finding mine. Missed it the first time I looked.
     
  4. JC91006

    JC91006 Senior Member

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    I'm trying to identify which part of the "right corner" your pictures came from? Can you take a selfie type picture with you pointing at the section where the crack was located? I have this leak and need to find the source.............
     
  5. uart

    uart Senior Member

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    He posted more details of exactly where it is in post #17 above. 12 volt battery change and alot of water under it | PriusChat

    Can you locate the black plastic trim that runs down the edge of the roof line (both sides)? It's kinda where the roof "gutters" would have been on an older style car. Well it's *underneath* that. You've got to pop the back of that trim off to see where those photos were taken.
     
  6. JC91006

    JC91006 Senior Member

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    Ok, I think I know where to look now. But thinking if this place was the source, shouldn't the interior of the right corner also be wet? There is nothing evident above the battery, just wet underneath it. I'll take it apart later and see if I see any cracks. Hopefully that'll solve the problem. Thanks Uart.
     
  7. uart

    uart Senior Member

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    I haven't personally seen the problem, but according to those who have apparently it just gradually seeps through there and gradually trickles down along the inside of the metal bodywork until it reaches the wheel well where the battery is.
     
  8. JC91006

    JC91006 Senior Member

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    That would make sense, it is hidden behind the plastic molding that runs along the right side of the car. I would think this could be a potential safety problem because the brake control power supply is situated back there. Not sure what would happen if the water overfills the battery compartment and gets to that unit.
     
  9. uart

    uart Senior Member

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    I've not heard any reported cases of this happening though.
     
  10. Dirtnapper

    Dirtnapper Member

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    I might have the same problem, I posted my issue. Is this not covered by Toyota??
     
  11. hyo silver

    hyo silver Awaaaaay

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    I've also noticed this standing water issue, when I replaced the 12 volt recently. I did not see any obvious signs of entry, and the water appears to have been there for some time. There was a bit of rust, but I wiped the area thoroughly and sprayed WD40 liberally to displace the damp. Now that I'm aware of the problem, and I've seen this thread, I will take a much closer look.
     
  12. uart

    uart Senior Member

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    I expect it would be if you were still within the general warranty period.
     
  13. TampaPrius.com

    TampaPrius.com Active Member

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    I have also seen them leak from the holes where the rear bumper retainer attaches to the quarter panel. This is more common when the rear bumper has been replaced or had body work. Sometimes body shops will re-use retainers with broken clips and the bumper sticks out a little farther than the quarter panel and acts like a shelf to catch water and it trickles in through the mounting holes. A new retainer is about a $25 part and loosening the rear bumper, installing a new retainer while using the body sealer that edthefox5 recommended and reattaching the bumper will pull it in flush and stop the leak. Sometimes aftermarket replacement bumper just don't fit properly.

    Another fix for someone who does not want to spend this much time and energy/money is to drill a small hole in the floor so the water can drain out. This is not ideal but probably better than riding around with 2-3" of moldy water rusting away the floor pan.
     
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  14. uart

    uart Senior Member

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    Lol, the old drill a drain hole fix, I'd almost forgotten about that one. I've used that "fix" before on many an old beater. :D
     
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  15. dorunron

    dorunron Senior Member

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    Yup, did the same thing on a old Chevy Truck I used to drive. Drilled some holes in the front of the bed so the water would drain out. Without them a lot of water would be in the bed after a storm when I parked in the driveway. Really full if I backed in as the water ran off the roof and dumped into the bed...
     
  16. kuz

    kuz New Member

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    I was having the same issue. My car would smell musty after hard rains and I couldn't find any moisture in the car (checked all the carpet all the seams). Finally, when looking at my 12v aux I noticed 2-3 inches of water sitting under it. I couldn't figure out where the leak was coming from and I ended up on this thread. It took me a while to understand what I was looking for so I'll ad a few pictures zoomed out for anyone that is confused by the placement of the crack.

    I have a small crack in the same spot as the op so I'll try some silicon on it or something simple at first and see if it helps. Great work, saved me a ton of time trying to figure out where it might be coming from. (the crack is really small but I could see how over time it could add up).
     

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  17. spuddybuddy

    spuddybuddy Junior Member

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    Found about one inch of water underneath my accessory battery when I went to replace it yesterday. Found this post and lo and behold, a tiny crack behind the retaining clip for the roof trim (just like khp reported). Will try to get some silicone sealant on it before the next rain.

    Thanks for the helpful post!
     
  18. khp

    khp Member

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    Glad it helped you out. I actually found the info here from previous posts about this same problem. This forum is a great source of information. Lots of great help from many different sources. I did this repair a couple of years ago to both mine and my daughters Prius Gen II with silcone and it's still working fine.
     
  19. Beachbummm

    Beachbummm Senior Member

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    I found water in the area too, I removed the small rubber plug in the bottom let it dry out and sprayed it with rubber undercoating to prevent rust or future water build up...both my prii have the same issue
     
  20. tinsandwich

    tinsandwich Junior Member

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    I too, had this problem, not just in the battery well but in the spare tire well also. I used silicone in the same areas noted by khp. I found out about this problem area by typing in some phrase, in a you tube field, related to finding auto body leaks and found a video showing the area and how to fix it. Unfortunately I am unable to cite the person who posted the video because I don't remember his name but I think he happened to be Polish. Fortunately his video was easily understood despite the language barrier. I am grateful to both khp and the Polish fellow for pointing out this time-saving fix. (Think I might try some of that stuff edthefox5 recommends if the silicone lets go however.)