First thing that pops into my mind is possible low voltage at the power post. Do you use something such as a Progressive Industries EMS unit which protects your unit and makes it possible to track the voltage? On our last outing, I couldn't run both of our AC units because one leg of the 50 amp circuit was only about 104 volts, which caused my EMS unit to shut down power to the MH.
If you are still on the trip, at least check the power post with a voltmeter. If low voltage isn't the problem, then it becomes a question of possibly the thermostat or the AC unit and I can't help with that.