hydraulic leveling jacks will not extend

I have a 2004 Four Seasons Hurricane class A with hydraulic leveling jacks. With engine on and e=brake engaged I an hear an electronic click when I toggle to every position on the floor plate. The floor plate on switch lights up OK and the 5 amp fuse in the floor plate is good. Hydraulic fluid level in the reservoir seems normal. Other than the faint clicking I hear when toggling to front, rear, right or left, I am not getting any lowering response. The control box underneath looked OK with no obvious damage or leaks. Any ideas? Is there a seperate hydraulic pump located somewhere?