a few weeks back I post something about my water pump were the good sam tech told me I need to replace my water pump. The reason he said replace it was while camping and hook up to city water my fresh water tank fill up. Just got back from another camping trip and I was hook up to city water and my fresh tank never fill up, so I guess the tech was wrong about my water pump needing replacement.
Probably not the pump itself but a back flow prevention valve built into the head. It may have had a piece of debris lodged in it which would make it appear to have failed and it could have cleared itself when you used the pump. The tech might suggest replacing the whole pump because itís easier than fixing the valve. Just guessing really but thatís my thought.