Welcome to the pup forum!
Converter query- when you plug your a/c (refered to 'shore' power) line in, the converter (should) automatically turn on. Since you have a 12V battery on board, you may need to disconnect it to test for converter function. Once the battery is unhooked, plug into a/c power and see if your LP detector and interior lights are working. You should be able to hear the converter fan running (might have to get on the floor and put an ear to it- they are fairly quiet).
If your air conditioner is working when plugged in to a/c ('shore') power, then all your a/c outlets should be working also.
As far as the lift system goes, I have no clue! I haven't encountered any problems yet (knock on wood) with our lift system. A Call to Jayco may be in order.
Camping is just a relaxing way to practice for being homeless. :Flag:
2009 JKU TV (Its a Jeep thing...you wouldn't understand!)
2000 Quest 8U PUP