06 Sonata Ltd Can't defrost rear passenger windows

berned_you

Ugh. I just got a 2006 limited which i purchased from my father two weeks ago. Since then the interior has been fogging up very badly. The rear window defrost works great and the front window one as well. The front side windows can be defrosted at least 90% - manageable. The rear windows are almost constantly fogged up. It's winter here and cold but I've never had this happen in my other 2006 GLS sonata. I've tried the automatic temp setting and also manual as well as having the AC on and nothing seems to work. This is a big problem. The outside temp reading is always about 20 degrees higher than actual but even when it reads below freezing I have fogging up problems. My dad said it was never like this for him and he's as honest as they get. Any suggestions??

propwash49

Does your car have a fresh/recirc switch? If it does, and you have it in recirculate, then you are constantly recirculating the interior air throughout the system. Every time you exhale, you are expelling more warm, damp air into the car's interior. In cool temperatures, this can result in the windows fogging up quickly. If you have such a switch, put it in "fresh" and see if that helps. Good luck.

berned_you

Yes, I have recirculate off. We even changed the cabin air filter in case that was too dirty and preventing enough fresh air intake.

fushigi

Agreed that the fog is caused by moisture in the air. So, the solution is to find the source of the moisture. It doesn't take much so the source doesn't have to be a running faucet; it may be a drip off of something. Or a spilled drink that soaked into the carpet/seat cushion too deep to be picked up when it was cleaned. Or damp (sweaty) clothes/shoes being worn (or snow off said shoes). Or damp/wet cargo of some sort (laundry, etc.). There could be a seal that's not sealing right or drain tube that's clogged (maybe frozen) causing a backup (mostly a factor if you have a sunroof). Or a clogged drain hole at the base of a door.

For existing moisture I'd suggest airing out the car thoroughly. If you park in a garage just leave the windows down for a few hours.

And as a rule make sure you tap off as much snow as possible off your shoes before entering the car.

backy

Also be sure to check the spare tire well; if there's a leak in the trunk it can accumulate water.