Hatchback leak from heavy rain

ASAP either repair or replace the hatch seal. It won't be inexpensive, but it will be worth it. Water inside a car is not good, water inside a Prius is "-a bad thing-" (tm). You could try silicone spray if the rubber is just a little dry and stiff, but usually it's damaged and has to be replaced.

Don't put off repairing it. If the water gets into the electronics it will cost -a lot- more. For example, the traction battery is right below that leak! Water and electricity aren't a good combination!

 

My 2005 hatch started really sticking some when I would open it. I figured I might have to replace it eventually so I traded it instead!

 

I think it would have been cheaper to fix the sticking!!!

 

If it rainy hard, and I open my driver's door or passenger door the rain leaks onto my seat. Has anyone else experience this? The rain just gets on the edge of the seat and it dries. I guess it is no big deal. I was just wondering if it is just my Prius 2010.

I started a thread about it here => http://priuschat.com/forums/gen-iii...eats-when-doors-opened-during-heavy-rain.html

 

Just did the same thing but I have more than one leak. That one was the worst however. If you pull the rubber grommet back from the car side (not the upper side attached to hatchback) the sheet metal there is very thin and easily distorted. Mine had like little ripples . I tried to straighten it but I added a bunch of sealant around it to just to be sure. That might explain the leak on the passenger side leading to the 12v battery but not the driver's side. I think it's coming from the welded seam that the hatch seal clips onto. I found several small gaps in the seam, although I didn't see how water would find its way in since the seal is there. On further inspection however I noticed that water wicks its way up the underside of the seal via capillary action presumably. It might not seem like much (no pun intended) but over several feet of seal, quite a bit of water can wick up, especially once dirt and grime has accumulated. Needless to say I wiped it off with alcohol and applied more silicon goop in various areas. Haven't looked at taillight lenses yet.

For sure the two vents are also a potential leak spot. Both of mine don't look like they are very well sealed as they are only held on by clips and the sheet metal (again very thin) looks a little rippled.

Can you tell this was a salvaged car? Well, I got it for about half price and it's a package 6 gen ii so I can't complain.

FWIW, the traction batteries (all six of them ) are fairly tolerant of moisture. I actually had water spill all over one of them once (don't ask) and it was fine. If you think about where the nominal 208v is developed, it's only at one spot, where the battery connects either to the big contactors or in my case in a couple of junction spots and Anderson connectors. I disassembled one of the batteries that had been sitting in the spare tire well which had a lot of water accumulated. There was no corrosion on any of the battery posts, interconnects, etc.

 

A leaky seal was your motivation to trade up to the 2010? Man, you were READY, huh (grin)?

 

So did you get your leaks fixed? Any advice for us as we have a similar leak on an 05 Prius that just started. Back door gasket looks fine and not dry rotted or cracked upon examination? Leak seems to be around back door, though. Water is running inside the ceiling and running out onto the left side of the back seat, just over the seatbelt - right next to the window.

 

This thread may help:

Water leak...into spare tire area etc | PriusChat

Check the hatch door frame for cracks and check the antenna base on the roof.

Good luck!

I also saved some pictures from other threads but I can't find the links now. So I just upload the photos here:







Found one link:
Mildew under rear passenger carpet | Page 2 | PriusChat

 

The 2nd picture in "a wimpy diyer" photo above is exactly where i had water leaking into right passenger side rear battery area and accumulating in the battery area and spare tire area. It was a small crack exactly where the red circle is in above picture. To test, i out a piece of duct tape to cover and no more leaking. I am going to fins something more permanent later today. Thanks for the image ( i have a 2005 prius).

 

I had a leak on my 08, best I could tell it was leaking at the upper left section of the rear hatch. When raised up there were what looked like very small cracks to the left area of the hinge. I just cleaned the area and spread a thin coat of silicone rubber around the area. It was leak g all the way to the rear small storage compartment before but after the fix it stopped.

 

I have been puzzled and frustrated with a water leak in my 2004 Prius to date until I read some of the other comments and suggestions in this forum. A few years ago I took my Prius to a local dealer in the Atlanta area to try to fix this problem. After they evaluated it they told me they located the problem and the fix was to replace the gasket seal in the hatch lid for a small fee of $300. Not knowing all the issues other people were having at the same time with this problem I chose to have the gasket replaced. I did not see any leaks for a while until a later date when I was installing a backup camera and needed to access the well under the left storage compartment to run a wire under the foldable cover. There is small a amount of water just sitting there in a crease. Luckily I only saw a very small amount of water in this area so I accepted it as a minor issue. That is until recently that I wanted to explore that area to locate the true cause of the problem. To my surprise when I felt further up from that well to the insulation/noise reduction material above the tire area, the entire piece of insulation was soaked with water. I immediately took the left side interior off and removed it with that material to allow it to dry. I then tried hosing that general area of the car, with the hatch closed of course, to try to locate the true cause of the leak. I thought to myself that it must be coming from a seal that may have become brittle. The only seals on the side of my Prius are for filling the gas tank and the small triangular shaped window. I hosed those areas separately to no effect. I did try hosing the roof then shutting off the hose but did not see any water leak(s). That is when I decided to check the Web to see if anyone else is having this problem. To my amazement, I could not believe how many people have located small cracks in the rear water channel areas of the car as the culprit of this problem. So I tried an experiment by first allowing water to only run down the channel. This confirmed that water started to leak into that well from the same area inside the car's interior molding above the well. I then placed some electrical tape over the areas with cracks after allowing that area to dry followed by watering the channel once again. Surprise ... no leaks! For now I'm going to leave the electrical tape over that area for the very short term to fully convince myself that I have found the source of the leak. I will later apply a filler such as silicone and/or flowable windshield silicone over that area to more permanently fix the problem. Since this seems to be a repetitious issue related to the vehicle's structural integrity, I would hope that Toyota would step up to the plate and remedy this matter; if not, then legal action such as a class action be taken against Toyota for such a defect.

For purposes of illustration, I took some photos of the cracks in my 2004 Prius:

3 views of Cracks are shown located on the driver side water drain channel at rear of the roof and under the top of the hatchback; suspect cause of leak in 2004 Toyota Prius:

 

Thanks RMK for your post. I am finding the same problem in my 2009 Prius. For me you honed in on just the source of the leak and helped a lot.
We had been getting water in the spare tire area and then this winter Toyota told us the battery froze up as it was surrounded by a frozen block of ice. They said "keep an eye on it." Not helpful.

Got worse and finally after 3 days of rain and a soaked car we had to dig in and find it..
After quite a lot of looking we decided we needed to take out all the rear trim. Not simple:


Checked all the usual places and nothing seemed to show. Then following your lead we tried using a pitcher of water running water down the drain gutter. If we ran the water from hinge of hatch or lower, no leaking occurred. If we ran it from higher up the rain gutter, like over the rear door entry as shown here it leaked.


Upon deeper investigation, we think we found the spot, the same type of seam crack under the mastic on the rain gutter down near the hatch.


It may be there and elsewhere so I applied silicone to the seams of both left and right rain gutters from rear door back to below the clip for plastic.

We shall see. I agree with the disappointment about Toyota. We expect to run these cars over 200,000 miles and over 10 years. That's why Toyota commands top dollars. At least the dealers need to be aware of this.
THanks very much for the time and effort you took to share this with us.

PS. I tried Toyota's TIS Site and a two day rental of repair manual to learn how to remove the trim.
Very glad I did that.

 

update 4/20/2020 - unfortunately water is still collecting!!
A bit frustrating.
Back to the "sealing" board.
-

 

sorry to hear it. check the hatch hinge points too.

 

The 12 bolt battery well is full of water too. There’s a rubber plug in the floor of the battery well you can remove but Many posters also report bad mouse infestation. So not sure if your area has that. Your car probably smells funky which attracts critters.
Remove the cabin filter behind the glove compartment and check the filter for mouse houses.
Pop open the engine air filter cover latches And look inside that air cleaner box for mouse house.

Best to just drill a Small weep hole in the 12 volt well rubber plug and the one under the spare tire if car lives outside. If you remove plug s mouse can just jump in. Be aware on g2 s with bad leaks the water will sometimes get under the passenger side carpet also so check if there soaked or stinky.

It sucks my car leaks too but it’s garaged. There’s a lot of flex in the roof to quarter panel area and it doesn’t help if you slam the rear hatch without opening a door to vent it. It already has little vents but you have to kinda slam the hatch. That’s tough on the corner welds in the upper hatch corners where they leak there and continue up the roof valley.

 

The water leak problem is one of the easiest to fix. Takes no tools or parts most of the times. Go under the car and remove both small rubber plugs and you are done. If water is in the middle remove and put back the big rubber plug. I drive my car without plugs since then and the car sits only outside winter and summer. No issues. When it leaks from somewhere it goes directly out.
If its huge leak from somewhere else then seal it but for this you dont have to do noting