[oldskewel]

Just a thought for something to check ...
I've got this problem on my 2011 LX, need to fix it in the next few months ...

There is a problem with one of the HVAC flapper controls that directs which vents the air comes out of. My OBD2 code is B1239, and I do believe it.

Somehow it is stuck in a position where the air cannot be directed to flow up over the inside of the windshield, as it should be able to. In foggy atmospheric conditions, this means the windshield will fog up, and the solution is to basically heat up the entire car interior so the inside of the windshield is warm. The only problem I've found with this workaround is the sound coming from the rear seat passengers, but it is something I'll need to fix.

So for you, I would check to see that air comes out at the base of the windshield when you've got the HVAC set to defog / defrost / etc.