I am Wiring a New Honeywell RTH6580WF Thermostat but there is no Yellow Wire at Thermostat. The old Trane thermostat only had 4 connections and the blue (C wire) was connected to the Y terminal.
The furnace is wired with 5 wires connected (including a yellow) as you would expect.
I’ve pulled a bit of the multi wire out of the wall at the thermostat and stripped some covering to see if the yellow wire was cut off, but no luck.
Can I jumper the yellow wire to another color in the thermostat?