Brand New 2022 Dutchmen Yukon 399ML Battery Question

[TSal]

Hi all!

My fiancé and I recently took a week long road trip to pick up our brand new 2022 Dutchmen Yukon 5th Wheel. It's the 399ML floorplan if that matters. We're hauling it with an F350. We've had the trailer a grand total of three days, and as I'm sure all of you can guess, we're already confused.

The first night we just found a Cracker Barrel to park at overnight and we had lights on just long enough to set up the slideout in the bedroom, sleep, and put it back after breakfast to get back on the road.

The second night we tried to do the same in a Walmart parking lot and had no lights. The slideouts wouldn't work. Ever since we have no electricity. The leveling panel doesn't even light up anymore. We'll be back to where it will be parked in a campsite tomorrow, and we're wondering if our two marine batteries are shot already?

Do the batteries charge at all off of our truck?

Will everything magically work when we connect to shore power and will the batteries charge then?

Did we just get faulty batteries from the dealer and they need replaced?

Of course any other advice will be appreciated.