Truck Repair: Vent not working, gmc yukon, hvac controls

Question
I own a 96 GMC Yukon and have 2 questions for you.  First, the Vent no longer will switch to defrost, or to the top vent it will only blow to the feet regardless of switch position. Second, the lights in the dash (ie radio, HVAC controls) are no longer working Dealership suggested a short but could not find anything.  I am of average skill mechanically.  Can I fix any of these myself.  The defroster not working is of most concern to me as I live in Canada and cannot live without the defroster (BTW the A/C blows cold Heat works fine and the fan works perfect it just won't switch between the different settings: head, feet, defrost etc).

Thanks,

Adrian

Answer
Hello Adrian,
First for the defroster.
Behind the center of the dash, like behind the ash tray, there is a little motor that runs a switching door in the heater housing.
My guess is you probably need to replace that motor.
There is another motor beside the gas pedal that switches from floor to higher outlets, but the one in the middle switches it up to the defrost if I am not mistaken.
Van