APU Works but Inverter stopped working

is it a smart inverter. ours at work have a red or green light. after a total of 2 hours usage. it turns off until it resets after like 24 hours. red light will be on. also try resetting it

 

theres a on and off switch. try it first. maybe tripped from setting awhile and batteries dead

 

Do you have a voltmeter?

If so, take a reading across the terminal connections on the inverter.

If you have a minimum of 12v, and better 13.5 or so, then your truck is giving it power. It might not be clean power, or regular power, but it's a place to start.

 

Look where the outlet plug is to see if there's a GFCI reset button.

 

I would be somewhat surprised if you can see the inverter from outside the truck. They are normally located in the sleeper, mounted to a cabinet or under the bunk. I can imagine ways to put an inverter outside the cab, but that would add expense, because inverters are generally fairly fragile and would need protecting with a case.

If your batteries were drawn down or incapable of fully charging, your inverter definitely would not work right when the truck is turned off. In some trucks, the computer might even disable the inverter circuit in order to protect the ability for the truck to start.

But that's just explaining what happened before. You say that it is working properly now, without your needing to service the inverter at all?