I have a 2012 f-150 XL. I am currently having an issue with the air flow through out my vehicle. There is air flow but it is very low coming through the vents. I have had to change the blower motor and blower motor resistor and have it running again. The vent change actuators are working as well and temperature control is not an issue as well. I was just wondering if you guys had any idea on what the issue could as far as restricting the air flow through the vents.

 

Have you had a chance to check or change the cabin air filter?

 

I have already checked to see and my model truck doesn't have a cabin filter.

 

There were times when I had to remove the blower motor and use a flashlight and small mirror to see if there was anything blocking the air from coming in or going to the ducts inside the vehicle. Blower high seed is controlled usually by a Hi speed relay usually mounted on the firewall, but does not have to be on the firewall.

Did you try to run the blower motor when you had the motor out? If all that checks OK,there is a good possibility either one of the directional doors is jammed or maybe even some critters made a home in the duct work.