I do not know your specific coach. However, if shore water is flowing through to the faucets when the valve is on tank fill, there is something wrong with the valve. Slowly try turning the valve lever to both settings (city water and tank fill). Do this with the city water turned off and the city water pressure relieved in the coach water lines. Does it feel like just the handle is turning or the handle and valve is turning. There should be some resistance (minor but some) when the valve moves. There should also be a solid stop at each position.
2005 Newmar KSDP 3910 + GMC ENVOY XUV 37K lbs Moving Down The Road
The Avatar Is Many Times Around The USA
Nobody Knows Your Coach Like Somebody Who Owns One Just Like Yours