Blower controls not working

question I have is my blower controls are not working ie defrost, floor direction, or vent. the blower motor works at all speeds but I can't change direction. is there a vacume hose off somewhere or is the vent controlled by a relay, I pulled the dash apart but could not find any connectors unplugged or open wires?? It is a 1990 grand prix 3.1 liter

Thanks
Earl