Generator shutting off. battery power dissapears!

[ColinSiR]

I have a 99 bounder 36 diesel with a Onan 7500 watt gen. I have a electronic climate control energy management unit master controller that buzzes really loud while the gen is on and the "output shorted" light comes on and kills the gen.
It seems I lose 99% of my battery power after this even though my batteries are fully charged.....

Im not sure where to start looking. I might book it into the RV service store but Im worried Ill get hosed(electronic issues $$$$$$)

Also Im not sure if its related but I have 2 a/c units and neither of them blow cold air.

I have a feeling this will have to go in regardless before my big trip!
This is the unit buzzing and killing the GEN.


Any help will be awesome!

[ColinSiR]

I just wish I would have battery power after it buzzes and shuts off.
Also the generator will not restart because of weak battery power unless I start the main engine then it will start. Im at a loss!