Donpepe,
Yes, your complete HWH pump and reservoir are under your steps. I fail to see how Winnebago could not give you this information. If they have the last six of your vin, they can tell you where every nut and bolt is. They have for me, the last few times I've called them.
If you lay on your side, in front of the right front wheel, and look up, under the right front of the coach, towards the under side of the steps, you should see a clear, Plexiglas panel.
That is a cover panel for the circuit board that runs the entire HWH system. It looks like something out of a Star Trek movie. And yes, under your second step, the front lip, is the bolt that secures that step. Remove the bolt, and the step hinges towards the driver side of the coach. When you lift that step, you'll see the pump, manifold, all the solenoids, and the reservoir.
Now, I'm assuming that, when you were trying to operate all the slides and the jacks, that your emergency brake was set. Because if it wasn't (no one on a diesel parks without setting that brake because there is no "Park" in the trans on those), than your HWH system will not work. There is a e-brake interlock that must be activated prior to the HWH system to be operative.
If your e-brake was set, and you've still had issues, that interlock switch system could be on the fritz. I hope this helps some.
Scott
Scott and Karla SDFD RETIRED2004 Itasca Horizon, 36GD Slate Blue 330 CAT
2011 GMC Sierra 1500 Ext Cab 4x4 Toad
2008 Caliente Red LVL II GL 1800 Goldwing KI60ND