[folivier]

I know exactly where that hose connects! Look in the front passenger basement compartment and where the generator compartment slide knob is there is a tee. I think the line going up into the floor is the supply for the seat. Had that line come off the seat just before entering the Mobile tunnel. Kinda gets your attention don't it?
There also is a latch to lock the seat down if you don't use the air suspension. I think it is at the front seat base.