Have a problem this morning, went to head to work and the truck is blowing cold. The flow will switch between defront/panel/ floor ect, but always cold. Trick is up to temp, and when I move the temp dial can hear a slight noise. Sound like a bad blend door?

Also have had the fan resistor fail and the fan stuck on one speed. Replaced it (track had the resistor for automatic control even though the truck only has manual control) and it has failed again shortly after installing it. Connected issues?

Truck is a 2014 f-150 xlt

Its also -35c here this morning and wondering if possibly something is iced/frosted up.

Thanks

 

I will pass a similar issue I had with my sister’s car 3 days ago. Car was blowing cold air all the time. Her temp gage was normal, but it was dancing around a few degrees. When I drive it, I saw the exact same thing, no heat, car was normal temp, but the gage was moving around back/forth 15 degrees. What I found was her coolant was more than ½ empty. Once I gave the system coolant, heat was abundant! Now, why was it low? Next morning, I went out to start and check it cold, as it was warming up, I popped the hood, and the water pump was spitting coolant all over the place.

What I learned was the coolant was 25% full but did not overheat due to the temps was 20-35 at best. But there simply was not enough fluid to get the heater core warm to produce heat. Replaced leaking water pump and filled coolant, all is well now.

Moral too the story, check the small things first. As cold as it is where you are, the motor will not overheat but low coolant will cause no heat inside the vehicle. Good Luck!

 

Check the heater hoses and heater core.
Check the blend door actuator.
Check what this guy talks about.