It will help us better help you if we know what camper you have. Year make and model. A good way to do this is to add a signature with that information.
Does the thermostat control both the furnace and the air conditioner or just the furnace? Makes a difference how the wires are run and where they go.
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2009 Seville VF32KS
2019 GMC Sierra 3500HD Crew Cab Denali.
6.6 Diesel standard box.
Thank you. You did not include the model so I will just take a guess. If you have 1 AC the thermostat wire goes to it. There should be a control box that also runs the furnace. If in fact the wire is broken you will need to pull a new one from the AC to the thermostat.
Just curious -- how did you determine the wire/wires are broken?
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2009 Seville VF32KS
2019 GMC Sierra 3500HD Crew Cab Denali.
6.6 Diesel standard box.