I have the same problem. THere are many factors, but it is likely the 50 amp Direct Current circuit breaker that is wired from your batter to the hydrualic pump that pushes the slides. The pump demands more than 50 amps and trips the breaker. Mine was drawing 80 peak. The breaker resets and youcan continue.
I replaced the braker, and carry a spare as they aren't made to be repeatedly tripped.
There are those who recommend replacing the braker with a higher rated one. Montana is still using 50 amp in new units and mine worked fine for 2.5 years. A new breaker did not stop the problem.
I am guessing, but I expect the real cause is either the pump itself or the selonoid on the pump. THat is what Lippert replaced for another MOCer who was still under warrenty. SInce that might be an expensive fix, a spare curcuit breaker is my choice for now.
Don't hesitate to call Lippert directly. Your symptoms might be different from mine.
By the way, the first thing to do is make sure your batteries are fully charged and don't have any weak cells.