Inspect the Cabin Air Filter:
A clogged or dirty cabin air filter can hinder the airflow through the HVAC system, affecting the performance of the front defroster. Check and replace the cabin air filter if necessary.
Check for Air Recirculation:
Ensure that the air recirculation setting is turned off. Using recirculated air can trap moisture inside the vehicle, making it more difficult to defog the windows.
Bad Mode Door Actuator:
The mode door actuator is another component that can contribute to issues with the HVAC system, including problems with defrosting. The mode door actuator controls the direction of airflow within the HVAC system, determining whether the air is directed to the windshield for defrosting, to the floor, or to the vents.
If the mode door actuator is faulty or not functioning properly, it can lead to an incorrect distribution of air, affecting the performance of the front defroster. Symptoms of a bad mode door actuator may include inconsistent airflow or an inability to direct air to specific vents.