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Condensation on Inside of Windows (merged thread)

('14-'18) 
32K views 111 replies 52 participants last post by  ComeBackShane 
#1 ·
So I've had this '14 XT since May and have 19.5k miles with no major factory issues until now. I noticed last week after some really serious rain here in NJ that first thing in the morning, there was an INCREDIBLE amount of water on the inside of my windshield, it was confined to about a 9" radius just above the vents in the center of the windshield. Almost as if there was a bucket of water in my dash and it had just been evaporating and condensing into a puddle on my windshield. I cleaned it up and have had my eye on it ever since. Now I am noticing excessive amounts of moisture build up inside ALL windows. I've driven a ton of cars and have never had such issues with the windows staying fogged up for hours.

Now, the really concerning issue was this morning. We've had heavy snow and rain the last 3 days. I started the car today and let it warm up and defrost all the ice on the outside of the windshield. I come back 10 min later and the ENTIRE inside of my windshield, corner to corner, is DRIPPING wet. Had to get a towel and wipe it all away.

What the heck is going on?
 
#3 ·
Try running the A/C with recycled air for the next few days and see if it dries out. You could also try one of those dehumidifying canisters that they sell at home depot intended for damp basements. If it persists bring it in, either way please follow up. I'm in SE PA so I have similar weather and I have found that if I don't run the defrost I fog up really quickly, a lot more so yesterday than before. Could be the weird weather.
 
#5 ·
Couple weeks ago I had would I thought was a huge build up of condensation (frozen) on the inside of my windshield. I would say it came up as far as yours did from the vents, it's happened a few times but nothing major like that. I've also noticed a hard rattle coming from that area when the temp plummets below zero... Maybe the windshield needs resealed?
 
#6 · (Edited)
That is my other hypothesis, that the windshield is not sealed properly. Today it seemed like it was dripping from the upper seals, though I could not confirm the source of the water dripping down the inside of my windshield. It was evenly dripping from edge to edge however, which would suggest a poor seal, perhaps exacerbated by the cold weather.
 
#8 ·
Use the AC. The air conditioning removes moisture from the air inside and deposits it outside. Using defrost also uses the AC and should do the same, but when the defrost is turned off the AC should be turned on.

There was a time, living in New England, that I thought AC was superfluous. (I only liked manual transmissions, non-powered rack and pinion steering, etc) After I finally got a car with AC I discovered it was not a "pampering me" wimpout, but was a safety feature that all cars should come with standard. This awareness came during a very very rainy season, where without the AC the interior glass was simply wet.

Years earlier, with my VW micro bus, I found winter impossible and traded it. I had to scrape the inside of the windshield to see. No AC there, nor heat really.

Air conditioning is the solution.
 
#9 ·
Your problem sounds pretty nasty, if I were you I would take it to the dealer and see if they will reseal it for you. I plan on doing that myself, I've never had this much condensation on the inside of my previous cars or anyone else's for that matter.
 
#10 ·
It could also be moisture from the floor condensing on the windows. If it's cold and dry try leaving your windows cracked open an inch or so. I realize this may not be easy if you park outside. If/when temps are below freezing the relatively dry outside air is great at drying out the inside of the car. If you have these conditions you could try driving with the windows cracked open and the heat on full.

At any rate leaving your windows cracked open when temps are below freezing will stop the inside of your windows from frosting up.
 
#11 ·
So here's a video of the moisture on the windshield last night. The floor and seats are dry, so it's not like my floor is soaking wet and evaporating on to the windshield. I've had many cars and never ever had moisture build up like this. It's dangerous, I have to get a towel to wipe it all away, but then the second I turn off defrost it starts to fog up as the glass is now dirty as all hell. I am seeing more videos on youtube though with this same issue, and even on some cars that I've had in the past. Perhaps this is just a circumstantial situation that will not turn out to be the norm. Good news is after blasting the ac, recirculated and heat for about 2 hours yesterday I had no moisture this morning!

The video is longer then necessary (my editing skills are nonexistent), you only really need the first 15 seconds.

 
#12 ·
FWIT, living in NJ where humidity is pretty bad during the warmer parts of the year and occasionally during the winter when temps changed radically, I used my AC sparingly (to save gas, I thought back then) and NEVER had anything like what you're indicating on my windscreen or windows.......NEVER.

I really doubt if this is normal. Using the AC to defog your windshield, at times, is advisable BUT you shouldn't have to run the AC all the time.

I wonder if the windscreen was not installed properly at the factory and some water is accumulating somewhere down in the duct work, releasing copious amount of moisture over time.......

Puddling as you describe it is abnormal......period.

Take it back to the dealer pronto and let them see the problem......and fix it. My guess is that the glass is going to have to be re-installed after being removed and the channel cleaned.

Steve
 
#13 ·
It's easy to test for a leaking windshield with a garden hose. Maybe after the temperatures go up a bit.

An alternative explanation is that some melted snow got into the fresh air intake by the back of the hood, and this is your source of moisture. Keep that area clear of snow accumulation, and see if the problem comes back.

In my experience, you also get a lot of snow packed into all sorts of unusual locations after wheel-spin happy low-traction vehicle dynamics test. I filled my airbox full of snow during one of these sessions once.
 
#14 ·
Besides the opportunity to introduce moisture into the inside of a car through tracked in water or snow, the average human expels three cups of water a day through perspiration and exhalation. Per Person. That's a lot of water, especially during a time of year when open windows are not normal. It accumulates if it isn't removed.

All modern cars' dehumidify the air when in Defrost mode, and also when the Air Conditioning is used. Other than leaving the windows or doors open and letting the accumulated moisture evaporate that way, the Defroster and AC are the only methods that will remove inside moisture.

This is an ongoing condition, not a temporary one. That means an awareness of the reality of biology and weather, and enough use of the car's functions to deal with it.

I'll bet there are few who have camped out in a "pup tent" overnight in freezing temperatures. Those that have will verify the unavoidable lessons learned about moisture and humans. Or how about those couples on Lover's Lane with the windows up... :)

Use your Defrost and AC every day and you won't have an issue.
 
#15 ·
Thanks, Dr. Science, we've all heard that humans emit water…….BUT the fact remains that this degree of puddling is abnormal.

AC will help BUT is not the cure. Not unless the owner has a huge perspiration problem going on……

I must have a special Forester since I haven't run my AC in several weeks including thru some heavy fog and rainstorms and still have a dry interior……..my luck, eh?
 
#26 ·
*clap* This was along the lines of my response as well, haha.

OP, i'm in Philly and had the exact same thing happen in mine. Mine is parked outside all the time. It was just the weather we had. Heavy rains caused high humidity and then it got cold fast. Any humidity within the cabin condensed on the inside face of the cold windshield first.

I finally got mine dried out by running the heat with the AC on for about two hours. Still have the drop marks on the windshield that i've been meaning to clean off.

and FWIW, I have a $500 hygrometer. Maybe I can report.
I have had my AC and heat running about 3+ hours a day for the last 3 or 4 days. Last night I got in my car after work and I had the same amount of moisture on inside of windshield, however this time it was ice. Incredibly inconvienient and no matter what, this is not normal. Under no normal circumstances (nothing about this recent weather is abnormal) should this be happening. I have checked the excess water drains under the hood and everything is free and clear. There is no excess water or dampness inside the cabin and unless I am urinating in the back seat, then there is no way my body is expelling enough moisture to cause this...(for the record...I am not urinating in the back seat)

I will first look at the cabin air filter. I have been meaning to change that as I have 20k miles already and it needs to be changed. Then I will look into this Damp-Rid and see how it works out. After that I would be curious to check out this hygrometer.
 
#18 ·
OP, i'm in Philly and had the exact same thing happen in mine. Mine is parked outside all the time. It was just the weather we had. Heavy rains caused high humidity and then it got cold fast. Any humidity within the cabin condensed on the inside face of the cold windshield first.

I finally got mine dried out by running the heat with the AC on for about two hours. Still have the drop marks on the windshield that i've been meaning to clean off.

and FWIW, I have a $500 hygrometer. Maybe I can report.
 
#20 ·
Thanks, I already knew that back in the 1970s………BUT, I repeat, I rarely have to use my AC OR my defogger very often ( in anything but the hot and humid summer months) and have NEVER seen the amount of condensation that the OP and Inspector have…….

I've had very little fogged windscreen glass in over the years BUT zero dripping……none at all.


Since 1976, my Japanese cars also automatically switched on the AC w/o the AC lamp illuminating. I think this has been pretty much SOP for many years and across all brands.

Perhaps the later SH/SJ cars are much tighter than the SG cars were.

That's why I suggested that water must be getting into the OP's car, one way or the other…….OR he exhales more moisture than I do.

Whatever, it'll be interesting to see what the dealer finds, if the car goes back for the issue.
 
#23 ·
It certainly sounds like a venting issue. I live in the Boston area so we see plenty of humid wet weather in the winter time. Plenty of snow left in the car from boots, etc. No way to avoid that. And during the winter months I've seen a heavy mist on the inside of my windshields after the first start when I'm defogging.

But, I've never seen it that bad.

My first suggestion would be to toss in some Damp-Rid to suck out the moisture. If you park the car and notice the Damp-Rid quickly doing its thing (converting to liquid), that implies there's a decent amount of left over moisture in the car.

For the windshield to be leaking that badly, I'm surprised there was no whistling or such sounds when you were on the highway. You're still under warranty so I wouldn't hesitate to ask the dealership to perform a leak test on the windshield and the moon roof. Same with having them check the HVAC system out. Could be a plenum door not moving when its supposed to.

So far I've left my system in Full Auto and only had to select the defrosters, front a and rear a few times.

Its also a good idea as someone else mentioned to double check the areas around the cowl for blockages. I would also take a look at the cabin air filter. Be especially interesting to see if its wet or plugged. Should only take a couple of minutes for that.

Good luck and please let us know how it turns out.
 
#28 ·
I skimmed this thread yesterday and thought, "poor guy needs to have his windshield reset". At the end of my work day I got into my car and was greeted with a *sheet* of thick frost on my front and rear windshield! And I mean thick, as in, I needed to scrape the inside of my windshield. The outside was just fine. And I had been running the defroster on the commute in, so the air should have been dry. No smell of mold, but minor frosting like shown in the video below

Taking my car in for the first oil change tomorrow and will discuss with the dealer.

To be clear, what I saw was way worse than what this guy is showing:

 
#29 ·
Look under the car for the A/C drip after it's been running for a few minutes.

Until you get this issue fixed, go get a DampRid or similar dehumidifying cartridge. I know it may temporarily cause the issue to become unidentifiable, but letting the accumulation persist just to find the source is not worth risking further damage to your interior, electronics, adhesives, and spirit.

Best guess is ice/snow by the wipers gully helped water get to where it shouldn't. It froze/expanded and cracked/ruptured something. [I pee in my front seat (tinted windows) but maybe snow from your boots, opening the snow covered door, scraper, brought the snow/moisture into the cabin?]
 
#31 ·
I have seen several instances a damp interior due to an exterior leak in the plenum just below the windscreen........apparently a flapper that didn't close all the way which allowed water to get into the HVAC ducting system where it sat and eventually released moisture into the interior......but that was years ago on much older cars.....

That also eventually caused mold issues.

.........and this never happened when we lived in South or Central Western NJ.........never.

We're outside Boston by 1.5 hours or less and it hasn't happened here for me either.....and my car is parked outside, too.

Perhaps my 2003 is so loose that air is constantly moving thru the interior, even with the vents shut?

Definitely NOT a biodome in my car.

I must be lucky.
 
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