Hi all. I own a 2014 f150 XLT and recently my heat/ac/fan all stopped working. It doesn't work on any speed and with how cold the winter is right now I need to fix it. My initial inclination was that it was the blower motor so I replaced it but found that did not fix the problem. When I adjust the heat controls I hear a faint squealing noise so I took a video in hopes that someone here can help me identify the problem. Here is the link:

 

2014 F150 Lariat Mine quit 2 1/2 hours from home -40 degrees checked fuse relays etc didn't help, after 1 1/2 hours of frustration I hit the dash with my fist and fan started.Worked all the way home that night.
It kept quitting, hit on dash worked again and again. Finally determined a lighter tap under dash on passenger side just below where resistor is was easier on my hand. Worked fine when I took to dealer, 2nd time they couldn't find problem but changed blower fan anyway, worked for a short time. Heard from another mechanic that resistor should always be replaced same time as fan.
Recently replaced resistor, now it works most of the time just ocassionily quits for a few minutes and then starts again. living with it like that for now.