defroster works, heater/ac does not

[lmadrigal]

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?

[maxwedge]

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