Helping a friend again.2003 f150 v6 5-speed not getting any air flow out of a/c vents with a/c on all others floor and defrost work fine. where would I start inside the dash? Fan is working fine help her please thanks.it 102 in Tucson today!

 

I'm in Tucson too and yeah, it feels pretty summeryish... I stole this from another forum:



There are two vacuum motors used to control outlet airflow direction.

Item # 1 in the diagram is the PANEL-DEFROST motor, item # 20 is the PANEL/FLOOR door.

If #1 is stuck in the defrost position, you will get airflow from the defrost, but only when the second door is not in the full floor position. If you switch the selector to FLOOR, the defrost airflow should cease.

Need to know whether this is the case or not before giving the next step.

The vacuum motors are controlled by the head unit, whether manual or electronic.

 

P.S.
If you want to test with my control unit, let me know. I'll PM you my address and stuff. I'm at the base of Mt Lemmon and since I work from home I'm here almost 24/7.

 

Could be a vacuum leak. Helped a friend with the same issue. Ended up finding a cracked/broken vacuum line rear passenger firewall behind the batter. Fixed the hose and fixed problem

 

Yes, that would be a great place to start. There is a vacuum tank between the battery and the fender. Usually if it's a vacuum leak it will start off by blowing out the wrong vents as you accelerate or other heavy load conditions unless the line is completely broken.

 

Will check the vacuum tank there is no strong air flow out of floor or def. vent but it does switch from one to the other. my guess no easy fix if it is the blend door or motors is there? thanks for the starting point will go from there.

 

It's all fixed nothing but time wasted the blower plug burned some wires a few months back bad contact at plug I fixed them but goofed up! matched wire color for color that runs fan backwards switched them on a guess have air flow out vents my goof. Thanks for all the help at least I didn't pull the dash thank god all is good Lee