It's been rather cold here in Ohio for the past couple of weeks. Almost every morning my wife finds her windshield with frost on the inside of the car. Upon visual inspection, all of the seals look okay and I have never noticed any leaks inside the car. Also, I am pretty sure this did not happen last winter. Any tips on finding a solution to this?

 

When you get to Oregon, the problem will probably go away

I would suspect moisture inside the car, probably water under the floor mats, maybe from a disconnected or clogged piece of drain tubing. I don't have a sunroof, but I understand there is drain tubing routed down from the sunroof channels.

 

Make sure the ventalation system is set for fresh air and not recirculated air.

snow that melts off your shoes causes the humidity level inside the car to rise and this humid air turns to frost on the inside of the windows.

Keeping the system on fresh air keeps the humidity level down and helps prevent frosting the inside of the windows.

 

This is what is going on:

Moisture inside the cabin is condensing on the inside windshield. The glass is so cold that it freezes over.

now the detective work and possible solution:

a) Where is the moisture coming from.
High humidity in the air. There is nothing you can do about it (may be you can .. read on)
When we breath, we let out moisture.
Wet clothing
Accumulated moisture in cabin due to leak or clogged drain.

b) Preventions or possible cure.

Clean the inside glass. Dust particles on glass help condensation to build.
See if the problem goes away on dry cold days
Look for wet carpet and trace the source. [why carpet ... water flows to the lowest spot]
Run the AC before shutting down the vehicle. What the AC does is remove moisture in the cabin ... in defrost mode it comes on. What we are trying to do is remove the moisture in the cabin the night before and when you exit, the air inside will be drier.
Turning on the ac when you start will also remove moisture and your screen will clear out quicker.

Note: If the AC drain is clogged, then the moisture is not removed. So if that is the cause of problem then the above will not help you.

Lets us know what worked and what made it worse.

Salim

 

My wife and I loved this comment :-D We cannot wait to move there. Winter temperatures seem to stay above 40 which is much better than Ohio.

Thanks for the tips Salim. I will clean the glass on the inside and then I'll have my wife observe it for the week. I will also check around for wet carpet spots... but, where are the drains located?

 

There are two drains you need to worry about ..
Sun roof drain pipe.
AC condensate drain pipe.

If these drains are not secure and free of clogs, then you might get the moisture inside the cabin.

Both of these problems have been discussed in past. Please use search, but if every thing is dry inside, there is no point in chasing the drains.



Salim