On my 2001 National Surf Side I think the engine has to be running before the jacks will turn on & operate. I can't check for sure as our MH is not parked here at home.
So, try starting the engine and see if that works.
2001 Fleetwood Discovery 38F, 2013 Honda CR-V, Roadmaster Falcon All Terrain Tow bar. Magalia, CA, iRV2 Supporter, Member FMCA