Do you ever go out to your car in the morning and find your windshield completely fogged up? You turn on the defroster, but it just doesn’t work fast enough, so you find yourself wiping the inside of your window causing streaks so bad, it may be worse than the fog? Can you tell that I have experienced this? Well, understanding how your defroster works will aid in the dreaded morning fog up, and get you to work on time.
The heater/defroster only works with fresh air coming into the car, so for the best defrosting make sure you have your dash board controls on the appropriate settings. There are two types of dash board controls.
Most domestic (Chevy, Ford, Dodge) cars have Max AC and Normal AC option. On these cars the fresh air intake door only closes in the Max AC position. So when you have your control on defrost, the fresh air intake is already open, allowing fresh air in, defrosting your window perfectly.
Most import (Honda, Nissan, Toyota) cars have a separate lever or button that say Fresh or Recirc. On these cars, when you need to defrost your windshield, be sure you have the fresh lever/button on and not the re-circulate. With the fresh button on, your defroster will bring in fresh air and defrost your window!
Now remember if you are one of those people that likes to drives your car with snow all over it. The fresh air to make your heater work comes from right bellow the windshield. So if that is covered with snow or ice you may not be able to get any fresh air circulating into your car, limiting the efficiency of your heater and defroster.