furnace wiring problem

Long story short. The furnace in the new TT comes on when you plug in the rig to shore power or take out the fuse and reinstall it.Tstat has no effect on the furnace.

I did some checking and finally found the wire from the Tstat designated for the furnace goes up to the AC but is not connected to anything. The wires from the furnace that also ran to the AC were bound together. (That would be a blue and blue/white wire off the Suburban furnace Separating those stopped the furnace from coming on when the rig was plugged in.


More checking and find that the blue/white wire from the furnace has 12 volts all the time. the other has none. Connecting the Blue/white wire to the green wire from the Tstat makes the furnace work "normally"..(I have not had the time to do a complete testing of all the possible scenarios for a furnace.)

But I still have the Blue wire from the furnace that is not connected to anything. I have no idea where it goes. I tried running it to ground, but that resulted in the wire heating up. So I don't know at this point what I need to do. All the wire diagrams I have looked at have been of little value to me.


I did test these wires for continuity and they all seem to be single runs to the stated points.

I posted links to photos but that didn't help much as they went nowhere so I removed the links.. I have them if anyone wants to see them.

Thanks,
Really need some help on this one.