Driving along after half hour of driving at 100km, suddenly the windshield fogs up completely. Air not on recirc. No fiddling with controls. It's cold outside. Driving in sub zero temp. Windshield will not fully clear in the inside. Any tricks for a fix or is my car not performing well? This is with the blower on full tilt for several hours.
It's a big windshield and I have found it can be tough to keep clear. One thing that helps is to thoroughly clean the inside of the windshield with a good cleaner like Invisible Glass. The off-gas from the plastic and other contaminants can leave a very thin film on the glass, providing a good place for condensation to stick. Another thing to try, in addition to turning off eco mode, is raise the temperature on the climate control.
We had the same issue because we were trying to use the defrost function on the touch screen. In cases of really cold weather this doesn't heat/defrost enough so you have to push the "front" defrost button (above the rear defrost button just to the left of the screen).
Good point. I assumed that was being used, but it may not have been the case. I drove through freezing rain a few weeks ago (about 75 miles) and had to stop and scrape the windshield every 10 miles or so. The defroster had no chance of melting the ice, which started at the top of the windshield and slowly covered the windshield until I had to slide down in the seat to see out. And that was with Rain-X on the glass. When I got home I had about an inch of ice on the front surfaces of the car.
Using the defrost button on the car right above the rear defrost that turns on the engine and you'll get the heat from the engine like a normal I.C.E. to clear off your windshield. Once the ice of snow is off your car turned off the defrost button and select in your heating settings defrost and feet. The heat pump should keep your windshield clear. Posted via the PriusChat mobile app.
The only thing that I can suggest is setting the temperature of the heat higher than you want it. If you set it for 68-70F, it might eventually start blowing cold air. If you set it for 76-80 you'll be super uncomfortable, but at least the windshield should stay clear. Open the windows if you need to cool off.
