if the jack works normally, when you operate it in manual operation, but doesn't work in the autolevel sequence, i would suspect the pressure switch on that jack.
when the jack extends, and reaches the ground, it has at least 180 to 220 lobs of pressure on it and the switch closes and tells the computer that the jack is down. if it is stuck closed, the jack wont go down, because the computer thinks its already down.
if it lifts too high, it is stuck open, and is telling the computer, that no ground signal is present, so add pressure.
either way, replace the pressure switch. RAP8003