It sounds like the sensor is no longer attached to the cooling fin in the fridge. They can vibrate off when traveling. Hereís a pic of it attached to the fin. Itís the white thing with the cable coming from it. When it falls off the fridge quits cooling but the freezer still works.
BTW, most RV refrigerators will cool down faster in gas mode than electric mode.
Bob and Joyce
2013 CC Silverback 29RL
2010 Ford F250 XL Crew Cab 6.4 liter diesel
ATU Local 788