defroster works, heater/ac does not

HI, my 2004 envoy acted up, when I went to pull into a parking space, the steering wheel turned fine but the front wheels felt stuck , it jolted and now it is fine but then I loss all use of defroster/heater/ac .and when I went back on the hwy home, suddenly the defroster worked (....and I heard a sound from right side dash, like a motor noise..(like a _motorcycle)
but no other heating/ac would come on....
I tried all settings and nothing works or adjusts....only the front defroster, comes out low, but heated..and with that noise. any suggestions?

Welciome to AF, possible actuator on the mode door is bad, tough without tracking the source of the noise.