First of all, your retractable TV mount, your Awning, your Fridge control circuit board, your overhead lights, and your temperature control panel all operate on your 12-VDC power system. Microwave operates on 110-VAC.
With all of this in mind, I recommend that you use a multimeter and check the voltage across the battery pair.
You should read around 13.5-VDC of the batteries are charged, you should read around 14.5-VDC if the Converter is trying to charge the batteries, but if you only read around 12-5-VDC your batteries are not charged and your Converter is not working properly.
Also, check the age of your batteries and check the water level in the batteries. You should always have relatively new COACH batteries and the water level should always be kept full.
And of course, you should check your campsite power and make sure the voltages are at the proper levels.