Just replaced my cabin air filter and now the switch to change from inside to outside air below the AC and Defrost buttons is stuck on outside air. I see the mechanism that controls the flap allowing outside air in or closing it off but I’m not sure why the switch is stuck. Any of you experienced this after replacing a cabin air filter?

 

Go to the bottom of this page and click on "related topics". Under the first post there, read some of the replies there especially post 20. It should help.