Heater blower switch?

[crash444]

Hi just wondering if anyone knows what could be wrong with an 08 Ford F350 with the 6.4 the heater blower switch does not work on 1-3, it only works on number 4 the highest setting. truck has 37000 miles on it. It doesn't matter where you have the setting set for either defrost or the floor or where ever the blower motor just does not blow, you can feel the heat very lightly but not like it was before. I know on the some chevy's they had this issue and there was resistors for the heater under the glove box. Does ford have this same set up?

Thanks in advance

[53 willy]

Yes the resistor in the heater box has gone bad, I fixed a wrecked truck and the wrong resistor got put back in and that is exactly what mine did, only worked on level 4, put in the correct sensor and it worked fine. Its behind the glove box on the side of the heater box, two 8mm screws to hold it in.