Fridge problem while towing

Chrismandyhenry

Have just changed tow car to a ssangyong korando and am getting the red flashing triangle on fridge when hooked up for towing. Have had car checked and it is registering a charging output and have checked all usual fuses. I know the car has to be running.
All other electrics are working just a fridge issue. has anyone had a similar problem.

thanks