Q: Defroster use AC for defog?

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Does the front defroster in a car use the air conditioning to defog the windows?

Hello - yes, the defrost function uses the air conditioning system to remove moisture from the air. The air is then re-heated using the heater functionality, and you now have hot, dry air to defrost the inside of the windshield more efficiently.

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What others are asking

Q: How do I defrost the windows?

The Defrost helps you defog your windshield by using heated air from the heater onto the windshield. To turn the Defrost on: Press the Defrost button located on the climate control panel. Press the Rear Defroster/Heated Mirrors button and...

Q: Air conditioner & heater problem

The problem you are describing is possibly caused by mis-operation of the "flapper doors" that control and direct air flow throughout the various HVAC outlets. These doors are operated by cable or by servos. It is also possible that there...

Q: When you turn on the defroster/defogger, is the windshield supposed to defog instantly?

This can actually take a few minutes - and depends on the temperature and level of moisture in the air inside as well as outside the vehicle. Two things happen when you use "Defrost/Defog". The air needs to be heated,...

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