I just de-winterized my 2019 Travato for the first time. All lines flushed out with city water hook-up. I wanted to fill the tank via tank fill with about a third a tank of water. I connected to tank fill vs. city water and ran water for 10 minutes. The gauge shows the tank fill is empty. Water did run underneath the unit while I was trying to fill the tank. The tank indeed was empty as when I flushed or ran sink water, there was no water. What could be the problem?
I'm a new owner so my knowledge is limited. On mine there is a compartment outside with the water connections and a diagram. It shows a knob/switch which must be flipped between two positions to either fill the tank or use the city water inside. You might check for that diagram or in your manual it may have the same info. Good luck.
When you connected it to the city water do you have a valve you have to rotate for the tank fill? I know I intended to fill my tank once and forgot to rotate the dial. 5 minutes later I checked to see where I was and that's when I realized I never turned the valve.
2010 Winnebago Vista 32K with a 2013 Mini Cooper S Roadster toad.