I found it. It is in front of the stern bed. There is a panel that looks like it can't come apart. The screws are deep in the carpet that covers it. When you remove the panel you have access to the floor and there is a well there that the pump sets in. Every web site I got doesn't have a manel...
I just got a Vista 245 and the shower water comes out in the cabin floor. Dose anyone know where the sub pump for the shower is. I can't find any access panels. I turn on the pump power and it shows a draw on the battery but noting happens.