I would venture a guess, your mechanic broke / disconnected a wire from one jack that tells the system that the jack is fully retracted. So the controller believes it needs to retract a jack. and runs all the time.
shouldn't be a hard fix, but it will drive ya nuts finding the wire.
2000 Newmar mountain aire 4081 DP, ISC/350 Allison 6 speed, Wrangler JL toad.