2005 Prius - Found Water Underneath the 12V Battery Fix

There is a 12V battery in the trunk area of the prius.
While I was cleaning the car, I found a pool of water underneath the 12v battery.
All you have to do is pull a drain plug that is underneath the car and let all the water out.
If you want to fix the issue from happening again, you just have to put some sealant on the gutter seams that are in hatchback area. They tend to crack and open up over time.

[@jalal6529]

Thank you very much. I was at loss for how to drain the water from the battery well until you clearly showed the plug underneath the bumper.

[@MrSunnyBhoy]

Thanks so much this is so helpful. I have a UK model with this issue and watched other videos which told me some wrong advice. I never knew there was a drain plug in there! They obviously knew about the potential problem and built in a part solution

[@Meowlico]

Wow thanks for the vid! I was changing my tail light when I noticed water was HALFWAY up the battery! I drained the water for now and found the cracks where the water gets in. Will silicone asap!

[@Ουρανία-ψ7σ]

Thanks for this clear and visual vid. I just put silicone on my 2006 Prius at the seams you showed. I kept getting a foggy back window, like the kind ya get when theres like wet clothes near glass. I hope this fixes the issue🦋

[@ypaut]

Huge service for cleaning the gutter

[@fauchergunner]

This vid really helped me. Thanks for sharing. From London England

[@thibautsoufflet44]

Hi from France. Got water in my 12v battery compartment coming from the top of the trunk. I noticed the water seeps into the foam on the top right side of the trunk then flows drop by drop into the 12v compartment.
Error codes P0AC0, P0AC1 and sometimes P0A90 readen with Dr Prius app.
My dealership changed the inverter. Problem is still here.
Dr Prius App says my Hybrid Battery is fine. I should check all the water problems and seal it... with my garden hose maybe. My Prius drove fine until I wash it 2 weeks after buying it. The next day Christmas tree happened. Now I hope my hybrid ECU isn't dead because of humidity. It's been 6 months now that I'm stuck with these error codes and my car won't run in electric mode.

[@Ουρανία-ψ7σ]

I've seen videos about the electric battery pack collecting water under it. The battery is large and sits under the seat in the back passenger seats. March 2019 my Electric battery started to spit out a bad smell from the prius backseat vent (from driver seat, if you look back, over your shoulder, it's on the right side, near back window) I took it to dealership, they charges me $3000 to replace this electric battery pack and only guaranteed it for 12 months. I'm certain there is a water issue. I need to find out HOW water is getting in. Thank you for this Dr. Prius app, I'll download for precise guidance.

[@thibautsoufflet44]

FYI I just repaired my hybrid battery, the faulty part was the battery current sensor!
Get techstream with a mini VCI cable is the best thing you could do to correctly diagnose your Toyota or Lexus car.

[@Ουρανία-ψ7σ]

@@thibautsoufflet44 ... congratulations, Thibaut Soufflet, current sensor sounds like a much less expensive cost than a new electric battery pack, wow...okay thank you for the clues and advice. I work on my car, I prefer it that way, when I can.🦋

[@bushandbeachaustralia]

Thank you 👌🏽

[@JaffreyH]

Could this be the reason why my Prius has computer problems and is completely dead? In mine there's water in the whole replacement tire area thx!

[@sufyankhanafridi302]

Yeah definitely that is the problem

[@user-fx4qz8pt3w]

Thank you so, so much!

[@FatalSnipz]

What tool did you use to pull the plug?

[@stoneblue1795]

Flat blade screwdriver would do it.

[@MrBobbyw121]

Finger