You can't possibly be serious about such an undertaking!  For goodness sakes, have you ever looked under the hood?  There's 220 volts pulsating through all that wiring - you could be electrocuted probing around in there.
         Back in the winter, I was replacing a heat pump when I was interrupted by a next door neighbor asking if I'd take a look at his furnace.  It's a good thing I stopped and followed him across the yard - he'd done some highly creative straight-wiring and his house was right before going up in flames.
        You'd be well advised to forget what you've read on these online forums, trash the do-it-yourself handbook, and call a professional to fix your HVAC system.  This stuff is a bit more serious than hooking up a DVD player and figuring out you need to switch some wires around to get a picture.