I had this problem this last winter on the way to Texas, on our Elk Ridge and it was my fault. First time it happened, I was raising the jacks, and got sidetracked & the jacks quit going up. Looked all over for the fuse & finally found the inline fuse & it was blown. The problem was that when I got sidetracked, I raised the jacks too high & they bottomed out & blew the fuse. I've even got a black line painted all around the legs so I'll know when I'm about to bottom them out. Replaced the fuse & all was well, until the next time I got sidetracked. Now I'm back to the routine of putting the blinders on, & ear plugs on when I'm raising or lowering the jacks.