I have similar characteristics but my 15 amp fuse was blown. I have taken out the blower fan which is located about an hour underneath your wndsheild wiper assembley. My fan worked outside the car so I took out the controller located under the fan. I test the connectors on the fire wall and found ground and 12 volts on the red and yellow plugs. I am assumming I need a new controller. Your situation sounds a lot like mine. Test the fan out of the car and check the other voltages. My system slowly stoped blowing air but seams to function otherwise. Cold gets cold hot gets hot.

Chris