climate control
 

I have a 2002 suburban,everything worked when I bought it. Now the climate control is driving me crazy,it seems like everyone from 1996 to 2004 is having climate issues.The only thing that works is the fan speed,the ac button and the rear defrostbutton. Heat comes out of the vents thats it. I have repleced both accuator motors and the computer climate control in the center of the dash.Nothing works. Checked all the fuses and relays.I was a top line mechanic for 21 years,so I know a little about cars,but this thing is driving me crazy. Does anyone know how to fix what is wrong.