Heater control.

Originally the heater/defrost switch would only (blow air) work on high. Most recently the control no longer even works on high. Any suggestions (cable, fan, etc)?

try the fan speed regulator under the hood/passenger side firewall/2 scews hold it in/it has a plug with about 6 wires/when you take it out there will be what looks like coils of wires/see if any are burned into/this is a dealer or junkyard part/about $10