Ford Focus Forum, Ford Focus ST Forum, Ford Focus RS Forum - View Single Post - air recirculation
View Single Post
Old 12-13-2012, 04:44 PM   #9
Focus Enthusiast
Join Date: Sep 2012
Fan#: 104180
Location: Petaluma, CA
What I Drive: 1997 Red Outback

Posts: 180
FF Reputation: 2 lddavis Good Standing Member
Buy-Sell-Trade Rating: (0)
how does it know if it is going to fog up??
Temperature and perhaps humidity sensors.

Recirculated air traps humidity inside the car and leads to fogged windows if the temp/humidity is right.

Some cars also use carbon monoxide or nitrogen oxide sensors to monitor interior air quality. I don't know if the Focus has one or not. In this case, you really do want that outside air when the sensor says so...
lddavis is offline  
    Reply With Quote