Well you get the gold star -- that 100A breaker had tripped! I though you that was surely a misprint though. A 100A breaker just to run a pump motor? It's true. I traced the wiring back to the house batteries and sure enough found a strange looking breaker with a yellow lever that had swung out of place mounted nearby. When I flipped the yellow lever all the way back over, I heard a distinct "click" and knew it must have blown the breaker. I went back inside, started the engine, turned on the unit, and when I hit the retract button, all the jacks instantly retracted.
So now in retrospect I understand a couple of new things:
- This is why the engine must be running to run the jacks. The hydraulic pump motor takes a LOT of power!
- When the rear jack bottomed out, I'm thinking the electronics kept running the motor on the one jack. The hydraulic pressure built up and caused the motor to draw too much current, snapping the breaker.
- When in doubt, always use blocks under the jack pads!
It am also glad I didn't have to go to the trouble of manually retracting the jacks with a drill, only to find out that would have done nothing to solve the real problem! Thanks again for pointing me to that 100A breaker.