I noticed when I hookup the hose to the sewer flush hose connector in the side of the trailer I do not hear or see any water going into the tank or coming out it seems like it was plugged up.I traced the water line from behind the sewer flush connector to a water valve and the other side of the valve goes to the black tank to flush with water. It seems like the valve is plugged and not letting the water go through. What is the name of this valve? I called an RV parts store today and they had no idea what I was talking about.
Mine didn't work when I took delivery. I had the dealer replace it under warrentee. If you can, that's the way to go. Unfortunately, the factories are known to install quite a few in backwards. Mine was. It's sometimes difficult to locate and get to the valve, I would have the dealer do it.
Sorry, I just saw that you bought the trailer used. If you can find out where the valve is located and can reach it easily, then you can do it yourself, otherwise you might want the dealer to do it. I don't know if they get plugged, but they do fail and are frequently installed backwards.