I am looking for help. I have a 2017 3.5 eco. The blower for ac and heat quits working once the truck warms up while driving on the highway. It will work upon startup but once you hit the highway the blower quits. On fan level 7 it sounds like you can hear the blower motor but nothing comes out of vents. On level 6 there is nothing and you can’t hear the motor. If the truck is parked and the engine cools a bit the blower will work again until the motor heats up then it will quit. Any thoughts?

 

Check for DTCs with FORScan or a diagnostic scan tool if you have the ability. Sounds like an issue with Blower Motor Control Module. It is an integral part of the blower motor assembly. Easy to get at if that is the problem. I'm assuming you have manual controls. The motor for the DATC is the same.