Description
Replacement Switch.
The Heater Blower Switch is what actually control the fan speed by reducing the amount of electrical current going to the blower motor. When everything is working properly, setting the fan speed at its lowest setting, for example, will tell the resistor to restrict the amount of current to a low level. But if the resistor burns out or wears out from corrosion, there is nothing to reduce the amount of voltage going to the blower motor for the lowest fan speed, so it will most likely get the maximum current and run at full speed. When a resistor fails, the fan will often run only at higher speeds or the highest speed, no matter what fan speed is selected.
