AC doesnt work, bad control unit?

[BDog21]

i was installing a new stereo the other day in my 99 yukon and must have touched a wire to the top of the ac/heater control assembly cuz i could smell something burning and saw smoke coming from right in there where it was, and ever since then it wont switch between floor vents/defrost/ front vents etc and my ac doesnt work in the front, it has rear ac controls and that still works fine, but the front ac doesnt work. if i pull the assembly out the rear ac stops working as well.

i pulled the control assembly out and the switch behind the knob that controls the blend doors for floor/defrost etc has 6 terminals on it, im not sure which ones i need to put my ohm meter on but if i put it on any one of the 3 on the left and the other side on any 3 of hte other side i get about an ohm, and as i turn it it goes to open resistance about 3/4 of the way turned. i was just double checking to make sure im replacing the rright part since that control assembly is pretty pricey...

btw i checked all fuses and all of them are good

 

[SunlitComet]

With out a schematic of the controller it is hard to diagnose the board. I would like to when I have time one day to dissect and make a schematic for the unit but don't have a fully function spare or enough bench equipment to analyze it. However I can tell you this, when the fan is in the off position 12 volts from the switch is applied to the board to force the the compressor circuit to turn off,force the vent to the lower floor position and the recirc door to shut off to draw in fresh air form outside. It does not effect temperature door at all. you will have to test the white from the mode door where it connects on the control head to see if the value changes when turning the know. It as wells as the other two motors draw power from the brown wire and ground to the black wire. With the blower on and you turning the mode knob you should see a smooth variable voltage on the white wire from the actuator. You should be able to use the control head connector as the test points.