Heater fan blows all the time

Your fan switch doesn't go to off like earlier models. The selecter ( upper slider ) all the way left should turn the fan off. The resistor pack is mounted in the air box under the dash. Those are in the ground side of the circuit and create the lesser speeds. If every resistor was burned open you would still get high and off.
I would say you problem is in the climate controller but I've been wrong before. Hope some of this helps.