I couldn't think of a better term. This is LA, so I'm not talking about frost, but I am sure you all know what happens when you get into your car on a cold morning.

The nights have been getting pretty cold lately, and I've been waking up to find my windshield covered in moisture, dew, condensation, whatever. This is a real problem when I have to hit the freeways at 6:30am and I can't see out of the windshield. This morning was especially bad, and I am not looking forward to tomorrow morning.

Let me make it clear, the tC isn't my first car. I drove my last car for about 4 years, and I would always overcome windshield moisture by turning on the cold A/C and directing it upwards through the windshield vents. However, this simply doesn't seem to work with the tC. Am I doing something wrong?

This morning, I turned on the ice-cold A/C at about two-thirds power and used the windshield setting to put the air on the glass. This didn't seem to clear up the foggy windshield, and even looked like it was making it worse. The air was blowing on the inside of the glass, but the moisture was building on the ouside, so the only remedy I could find was to use my wipers every time the moisture built up. I battled with the moisture for the duration of my 45-minute commute, but I didn't see other drivers having the same problem.

Am I just retarded? What is the officially correct technique for overcoming windshield moisture? Is the air supposed to be cold or hot? A/C or no A/C? Windshield setting or cabin setting? High power or low power? Windows open or closed? I had it figured out in my last car, but I can't figure it out in the tC. This will be my first winter with the tC and I need to figure out a solution.

Thanks!

 

well this has been happening to me lately as well, what i do is set it to windshield, windows closed (cuz its cold outside lols) and put it at the hottest setting on high w/ no ac ... and that seems to do the job well...

 

So it's supposed to be the hottest, not the coldest? Damn, I was way off! I had a theory about equalizing the temperature on both sides of the glass, so I figured I needed to make the inside as cold as the outside. Hmmm...

 

Use A/C for the "steam" you get inside. Usually happens when you get in your car on a cold night or when you have more people in the car.

Use heat for the dew we get in the mornings.

Or to not have this problem, throw a towel on your windshield at night. =]

 

weird - the moisture here in PA is always on the outside... windshield wipers take care of it. You're not leaving any windows cracked are you?

 

Yeah use the hottest temp with the defrosters to get that dew off in the mornings--

and the towel method works well, i put a big towel on the front and back window and works like a charm ;)

 

Well, the theory is correct, just not the practice.

Also, to clarify, the A/C is automatically turned on when you switch to front window defogger/defroster.

Living in the Winterlands known as Ohio, I have had plenty of experience with this, both hot and cold. What you were doing is creating an effect similar to what you see on a glass of icewater on a hot, humid day, where the water condenses on the outside of the cold glass. By putting your window defroster/defogger on the coldest setting, you are making the glass colder than the outside air, causing condensation. Believe it or not, your A/C probably (dont quote me on this) puts out 40-50ºF cold air, which im guessing is a bit cooler than the outside air, causing the condensation. You can fine-tune the temperature setting on the window defogger to match the outside air tempertuare, but thats more effort than its worth.

Simple solution: Full heat, fan on HIGH. Water wont condense on a hot surface no matter how much water you throw at it. If it gets too warm in the car for you, crack the windows or the sunroof, your windshield will stay clear. You should be able to turn down the fan after 5-10 minutes, depending on how cool and humid it is outside.

Drive Safely!

 

Well damn, whadaya know, it worked great. Thanks for all the tips. I put the fan on high with hot air and the condensation cleared up within a few minutes. I was able to turn off the heat after a few minutes and it never fogged back up.

 

haha i hate when that happens to me :/