I am cleaning up a wiring mess on a Suburban SF-30 furnace and according to the wiring schematic, I need to connect one of the t-stat wires to 12v at the furnace. My problem is now I have accidently mixed up the thermostat wires where they come out of the wall and connect to the furnace.
I have tried to ring them out with a multi-meter but there is no direct connection to the thermostat. I assume becaused the AC unit is also connected to the stat.
I have a total of 4 wires coming out of the wall, Red/12v, White/ground and 1 orange and 1 black both of which are for the t-stat.
Any ideas on how to figure out which wire I put power to?
2012 Toyota Tundra
2009 Komfort Trailblazer T254S