condensation inside windows

I came out of work today and my windows were so condensated and fogged up on the inside I literally thought somebody was in my truck cuz you couldn't see in. I had to squeegee the inside windows to see. all the doors were shut tight sunroof was closed I don't know where the water is getting in. anybody out there have the same issue? any suggestions on how to dry it out???

 

Same issue for me just this evening. First real cold spell of the season here, first winter with the 4R. I do mostly short trips so the interior doesn't get time to get to toasty usually.

 

Expected in Winter / Wet weather. Use this mode, it will automatically switch to fresh air and clear.

If your front vision is blocked open the glasses immediately.

 

Do you use the A/C during the winter? Remember that the A/C doesn't mean cold, it means air conditioning and is removing humidity from the air.

Also, I got some big desiccants that I leave under the seats to help keep everything in the cabin nice and dry.

 

If you you already run defrost with AC on in the cold weather to keep things dry, and you get out of the ordinary condensation anyway…then I would be looking for why it was so fogged up.

It could be normal winter stuff like water on the rubber floor mats (melted snow), or a weird weather quick change in ambient humidity.

But if rubber mats are dry, then I would check around under the floor mats for possible water intrusion just to make sure.

 

You can't run defrost AND NOT have AC on. This is a safety feature built into all cars. Defrost turns on the AC.

What usually helps with condensation besides AC, is to make sure you aren't recirculating the inside air. On the 3rd gen, it's a button.

 

If by "defrost" you mean the setting blowing against the windshield.... yeah, you can. Test it out on your 4R... both my 5th gen Runner and 3rd gen Taco pretty much live on defrost or defrost/ foot, and the AC is never on automatically.

OP, the condensation is a frequent complaint ,(though not usually as severe as you have it) and I suspect it's tied to temperature fluctuations and moist night air. What was once suggested to me was to turn the HVAC to recirc just before you park the truck, as this closes the air duct and in theory would keep the interior less prone to variances in outside temperature. I tried it, it worked... maybe...a little? I just allow a minute or two to defog the windows with the heater on high when I get condensation now.

 

It does activate the the AC, it just just doesn't illuminate the AC switch when it does. All vehicles since the 1990s have been like this. On my 2nd gen Tacoma I actually snipped the wire under the dash that automatically turns on the AC because it's such a power draw on the little 4 cylinder, but I can still turn the AC on manually if needed.

 

The AC is always on in defrost mode. If you listen, you should hear the AC cycle during defrost even if the AC light is not on.

Quick google search will show you this (one thread): Looking at the pic posted above, if that's a 5th gen...hit that button directly to the left with the U-Turn arrow and turn the light off. That will be the main culprit.

On a really old car, I would suspect a leaking heater core.

 

I'm going to look into this by physically checking the compressor in various modes; because I still dispute it. My Tacoma, for example, is a 4 cyl and I can feel it when I turn the AC on. I get no such sensation when turning on defrost. Further, the AC light doesn't illuminate and I'm not sure why it wouldn't if the compressor is activated. It illuminates when automatically activated in other settings (i.e. far left 'cold' + recirc).

My Civic does act as you describe when you turn on the defrost - you can feel the AC compressor and the AC light turns on.

 

Turn your dial to full heat and on defrost mode. Defrost mode does turn on your A/C which conditions the air (dries it out). The combo of dry heat is the quickest thing that will clear the windows.

 

Well, shit.

I stand corrected. I tried this out on the Tacoma and sure enough, compressor kicks on when the select switch is in windshield or windshield/feet setting, even thought the AC light does not come on.

That's embarrassing. I've left the selector in the windshield/feet position FOR YEARS. It's my default setting because it allows ventilation without blowing in my face. I mean FOR YEARS. Like, since I've been driving a fucking car.

Interestingly the compressor does not kick on when in windshield/feet setting with one click more towards the feet side... so the setting is like 66% feet and 33% windshield; so I guess Ima use that setting henceforth and forever more when I don't want the AC on.

 

There is not necessarily any source of water other than the air in the cab. Cold air cannot hold as much water (humidity) as warm air so when the temperature drops relatively quickly the water condenses on colder surfaces. This is what creates dew at night.