Ice/moisture on inside of windshield

It’s starting to cool off here and we had a couple of cold nights the other night but it wasn’t a huge temperature swing. Both mornings the following day I had a covering of ice on the inside of the windshield. So today (it’s been around 45 degrees) I went out to pick up a Christmas tree so probably a total of 25 minutes in the truck. I just went out to grab something and the entire cab had moisture on the inside of the windshield which I’m assuming is likely going to turn to ice tonight. It’s about 40 degrees right now so there hasn’t been a change in temp. I checked to make sure all my windows and stuff were closed and they were.

Is there any way to tell if there is a potential bad seal somewhere or something? I have an extended warranty so I can bring it to the dealership but figured I’d start here to see if anyone has any ideas.

Also, I had this truck all last winter and never had the issue once.

 

Could be a few things depending on the year of your truck and options that you have

3rd brakes lights on early models leak
Sunroof drains can clog and leak
AC drain hose can clog and leak
Water can come in from the front door speakers


You will want to find the source of the moisture.

 

It’s a 2017, no sunroof. Any tips on finding it? Just feel like it’s kind of a needle in a haystack

 

Check your 3rd brake light, it was a issue on 2016-2017 models. Go into a car wash and then check behind the rear seats for water.

 

You could have a leak somewhere, check to see if carpet is wet anywhere. Check behind back seat, I had a rear window leak on mine while still under warranty.

But it could just be humidity from the air, especially if the humidity has been high recently. Mine has done the same thing for a few days after a rain. What you describe isn't unusual here in GA where 80% humidity is the norm during some times of the year.

Keeping the truck closed up won't let the humidity out. On sunny days, even if it is cold, I'll open all the doors and let my vehicles air out for several hours from time to time.

Using the AC as a dehumidifier even in cold weather will dry out the interior of the truck. People who normally live in more arid areas never think of this. You'll still be blowing hot air if your temperature selector is set on hot.

 

Check your AC drain hose. Found a vid here, about 1min in https://www.youtube.com/watch?v=wZ6oupFWKoM

 

There are multiple threads on this topic ...

 

I found a couple that we’re just like “moisture is getting in, put some of those packs you get in shoes in there”. Hoping for some better direction.

 

Looks like it might be the 3rd brake light or rear window. Put my seats in the back down and it was wet on the plastic behind the seat

 

Do you have any in channel window vents? The weather tech ones on my dodge deformed the seal slightly and on certain days I’d have moisture built up. If not I’d check your third brake light or start pulling up carpet in the foot well areas and see if you can find traces of moisture.

 

I do have in channels. I’m thinking it’s more back window/3rd brake light but not ruling anything out. Moisture is right behind the back seats. 3rd brake light seems very slightly not flush against outside. Hoping to call the dealership tomorrow, bought it used last year and bought extended warranty but not holding my breath.

 

Mine leaked, they replace it with a much thicker gasket that looks like crap to be honest. I’ve been thinking about upgrading to a meso light housing instead.