If the levelers are not working (low voltage) with engine running it is an indication that the alternator is not charging the house batteries. Try increasing the engine rpms be and see if the voltage increases. If not check the BIRD/BIM. If at high idle, approximately 1000 RPM the voltage increases to over 13.1 (should be about 13.7) all is normal and the jacks should work.
I always leveled before shutting down the engine for that reason.
My current system will not level with engine running or ignition key turned on.
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