blower motor only runs on high i have replaced resistor and tried a different control head from ebay and nothing changed still just works on any suggestions

 

You have replaced the switch?

 

ya bought used one of ebay an still the same thing only high speed

 

the new resister and pigtail thats on the heater box i purchased from the local part store had the wires color coated on the pigtail to match the truck factory harness but one of the colors was in the wrong slot on the plug