I have a 2001 F- 150 that when a/c / heater control on high it works fine, but will not work in med or low.?

The fuse blows after a short while and some one mentioned that it may be a bad fan, but if it works on high is that still possible?I have a 2001 F- 150 that when a/c / heater control on high it works fine, but will not work in med or low.?
The resistor on the switch is bad and the default speed is high. Replace the resistor and you will have all speeds.I have a 2001 F- 150 that when a/c / heater control on high it works fine, but will not work in med or low.?
there is a relay under the hood in the firewall that controls the fan speeds. when it goes bad high is the only thing that works
You may want to post your F150 question in the Ford section, not Dodge, for a better response.
Blower resister

face mask