low voltage for levelers

Check your batteries when not plug into shore power or gen running. Post back.

There is no reason you cannot run your leveling jacks while plugged into shore power, I mostly do that when leveling. Pull into site and get situated, plug in electric and level and connect water and sewer THEN extend slides, saves many a skull injury.

Oh, do get the battery power looked into, it should be adequate to run levelers and slideouts.

Was the engine running? I get low voltage if I try to do it without being plugged in, generator running, or engine running.

I would think that "Electric Levelers" would draw lots of current when leveling. If you have a bad connection (E.G., lose, corroded, burnt or dirty) it will cause voltage drop across it and cause a low voltage condition at the control unit. If you have a bad connection that has a .1 ohm resistance at 10 amps it would be a 1 volt drop from the source (battery) to the load (controller.) Measure the voltage at the control unit and the battery while trying to run the jacks. Compare the 2 readings. Is there a large difference? If there is, find the cause of the voltage drop. I would start controller and look for problems both on the positive and negative wires. It could be a bad ground. Then I would work your way back to the battery checking each connection and taking voltages (while running the jacks) until you find the bad connection. If the voltage is the "same" I would focus on the battery.

If you check your owners manual, you may find that the engine must be running to operate the leveling system. Your engine has a 140 amp alternator, and your converter might be a 40 amp output.