My HVAC blower switch only works when I put it on 5 (the highest setting). What needs to be replaced (besides the whole truck)?
This symptom usually points to the blower motor resistor.
Thank you very much!
You may find that the original resistor pack was burned out due to the blower motor dragging.
Often, a dragging blower motor will cause the resistor pack to burn out, so if you are a gambler, you could try just replacing the resistor pack and see if the new one burns out in short order. If it does, you need a blower motor as well. If you don’t want this hassle, go ahead and change the motor and resistor pack.