You can bridge the TH wires and go to the outside compartment of the furnace.
Check the LED's for fault.
You can reset the switch on the blower motor.
The sail switch and high limit switch are in this circuit of the reset switch, so any open circuit will not start the furnace.
2014 Ram 1500 CrewCab 4x4 5.7 Hemi 3.92 Rear and Air Lift 1000
2005 Jayco Jay Feather LGT - 29Y GVWR-7000 lbs.
Dexter Axle Lift 4-9/16" - installed with sub-frame.
Pro Series 1200 lbs. WDH with Double Sway Bar.
Champion 3100/2800 watt Inverter/Generator-Onboard Solar Power