Understanding TriPac-E Shore Power System

I have a 2011 Freightliner Cascadia with a TriPac-E and an inverter. My question is about the shore power.

When I'm taking time off, I will park the truck and connect it to an outlet. I enter the truck and tap the power button once. I will then tap the power button three times, then two times, then three times. That is supposed to activate Shore Power mode. The LED bars on the left will turn green and go upwards -- I believed this meant that the system's batteries are charging. Then I can lock up the truck and leave.

After some time, the inverter will turn itself off and have a code - E01. The APU's batteries will be dead and the truck batteries will also be dead. The truck requires a jump, even if I use the main battery cut off switch next to the driver's seat.

When I connect to shore power is it supplying power to everything in the truck? Is the electrical power going to the inverter only? Is supposed to be charging the four APU batteries? Is current supposed to be going to the truck batteries too?

I guess I'm asking what should I expect from the shore power system. Since my batteries & inverter die, I am wondering if it's user error or bad component in my TriPac E system.

Thanks.