Behind glove box.
Either the switch itself is defective, or more than likely the Blower Motor Resistor Pack is defective. This is a common symptom of a defective Resistor Pack.
If it works on some speeds and not others, the most likely problem is a defective Blower Motor Resistor Pack. It is located near the blower motor.
It can be the resistor pack on the evaporator case.
Defective heater resistor pack.
Its located on the passengers side of the vehicle under the dash right next to the recirculating vent and the vacuum motor...........
Possibly defective Blower Motor Resistor Pack.
The resistor pack is probably damaged - this seems to be a common problem. The replacement part should be available from a still open Chrysler dealership for less than 20 usd. Replacement is very simple and easy.
Check the resistor pack on or near the fan , it may have melted and needs to be replaced.
Defective Blower Motor Resistor Pack.
It is not a fuse problem. The HVAC resistor pack is defective. Replace it.
You have to replace the fan resistor pack. Open the glove compartment and lower the door, look in back on the firewall. Remove the two screws and the connector, pull out the resistor pack - replace it.
I would suspect you fan switch is not the problem but it is possible. Normally this is caused by a defective blower motor resistor pack. Inspect that before replacing the fan switch.