OK, there are no power wires there. It all works off ground in the ’99 & later yrs. The switch has 3 terminals A, B, & C. I think they are marked that way & A is the top one. The bottom one gets the black ground wire & I think you have that right. The other heavy wire (12g) should be dark green & go in the middle (B) & the smaller (20g) light green goes on top. I think you have the top 2 reversed. The dark green is for the blower & the light green is for the compressor. You probably have the compressor coming on all the time except when the mode switch is off besides the blower only working in the a/c & defrost settings.