air bag or air valve?

[winstonnews]

Hi group
Had to move bus to another job site. Luckily only 2 miles.
Drivers side air bag didn't inflate..the air pressure built in system and gauges
said air was up. No sound of air leak..??? also suspension dump switch doesnt
seem bring air down it has to slowly go down w time. Crawled under no audible
leak from bag.
Ideas or suggestions appreciated. When I have to move to another location it may
be further and these roads up here can be a challenge without one corner aired
up..
thank you
Rose Mary
JP'S White Bird
Southern Oregon Coast Range
Oregon