I'll start off the easy way...The BIGGEST Problem I've got with this car is the heater, being as I'm up in the hills of Colorado and winter is just around the corner...I kinda want it to WORK! LOL! And locating a diagram of the heater wiring and such. it blows out luke warm air, but only out of the Defrost setting, HOWEVER...When the heater is on, it blows out cold air through the main vents...And I can't seem to figure out why...

Can anyone lend a hand or give me a rough Idea where or what I need to tear apart to make it work correctly?? It is full of antifreeze, the heater core does not appear to be damaged, and it is blowing out warm air...but only through the defrost as I said above. I can tear into it no problem...Just have to know what to look for, or where to start!
Thanks
Nate