Chasbo

D oes anyone have a problem with the windshield getting fogged up at three or four areas at the bottom, when the air is on?
Chas.

NJLEXES

Fogging on the "inside" or "outside" of the windshield?

If it's on the outside, that's normal if running the front defroster "cold" on these hot humid days.
When it's blowing cold, it causes condensation buildup on the exterior glass for sure.

As far as if it's on the inside, if it's excessive all over the windshield it might be indicative of potential coolant leak in the heater core....though that's unlikely. Again, it could be related to humidity. You might try watching the temperature adjustment to compensate or try running the a/c compressor (if you're not already running it)

Having owned many Lexus/Toyota vehicles they seem to somehow be more prone to foggy windows (Front & back windows) than other makes I've owned.

GrnIdKjun

My Ford and mini will do this if the air was blowing cold on the windshield and dependant on the outside conditions as well.

I traded the mini on the Lexus and haven't had the a/c on defrost much so haven't seen it yet but would expect it to happen in that situation occasionally.