I have probably run my jacks up/down 20-25 times this season, for the second time, today, I blew my LR 20 amp fuse, everything seems ok voltage to all 4 corners is the same, nothing loose or frayed....
I would suspect a bent jack, possible a dent or crease in the housing that is causing extra friction. Or, it could be a lack of lubrication. Does that jack run slower than the others? Is it making any sort of noise?