Low voltage!

Could be batteries getting worn if they are factory batteries only good a couple years but before I changed them it would be worth cleaning the connections and if you do end up replacing them I would go with interstate batteries over the OEM ones but that's just me

 

Getting new batteries in the truck will only help the problem for a while. With the inverter and depending on the TV you are using a good amount of power and the APU is detecting this running so that the battery's have more then enough charge to run. I got our shop to install a switch that would allow me to start the apu when I was going to be using any type of electrical appliance then the low voltage safety would not kick in and kill all of my stuff.

Maverick519

 

check the terminals on the batteries.

one could have come loose and your not getting a proper charge.

 

I was just about to mention that.
My last problem with the batteries was fixed by tightening the terminal bolts on 2 of the 4 batteries.
They were barely finger tight.

 

Try driving instead of hanging around the truckstop.

 

Do you ever smell rotten eggs, first sign of a failing battery, second stop at the auto supply and get a battery hydro meter, glass tube that measures the weight or density of the acid. It wi;ll tell before a gage when the battery is going bad. also disconnect your batteries from each other check them for a gauge they should all have the same voltage reaading if not the weak one is bad.

Oh yeah, don't be so touchy. Lifes too short.