Heater and AC Fan Switch Help??

My 1996 Tracker Heater And AC Fan Switch only has high and a notch below. Does not work at all on low or medium. What do I check or replace?

Thanks,

My 96 had been doing the same thing. Check to make sure the switch is not coming apart,as mine was. I took a wire tie and wrapped it around the switch to hold it together. Also check the wiring connector. I would sometimes have to wiggle the wiring to get it to work. In order to replace you have to buy a complete control head.

Check to make sure you have power though the switch on each speed. If you do there is a problem with the wiring between the switch and blower motor. OR. If you don't have power going to the switch at each speed its most likely a bad switch. Hope this helps

there is a resistor pack in the ac duct under glove box i think 3 or four wire go to it held in with two philips screws could be bad . i had same problem only high and low nothing in between. the fan switch wire run through resistor giving you different speeds.