[RussWhite]

Kurt,

I probably can't be much help since my coach is older and without an auto fill. But here are some thoughts anyway.

The green box with the red top should be the solenoid valve that controls the water flow into the tank. It would probably be a normally closed valve. When power is applied it opens and water enters. The sound should be a click, not a buzz. It buzzing that may indicate the control circuit is malfunctioning and trying to rapidly cycle the valve. This will draw lots of current and could result in a resettable circuit breaker tripping.
Guessing again, I suppose the valve would be controlled by the high level sensor in the tank. When you look at the potable water tank level on the gauge, what do you see?
On mine there are additional options for filling the tank beside the connection to the city water inlet. Near the top of the tank on both sides of the coach are connections where a hose can fill the tank - you just have to watch the level and turn off the water before it overfills the tank.

Sorry I could not be more help. Russ