Inverter or batteries

Have a 2015 gateway 42 foot fifth wheel. This is our 3rd season and the batteries do not seem to hold a charge. When the fidge is runing on the invertor it cuts in and out. Inverter is beeping all the time. Battery gauge show e but the volt meter on the leveling system shows 11.7 volts. Not sure if it needs new batterys or if something is wrong with the inverter. Any help out there? Thanks

11.7 volts on a 12v battery is all but dead....that is why your inverter is beeping at you. It is doing its job to alert you of a problem.

Have you kept up on keeping the water (distilled only) filled on both batteries?

Have you checked that your converter is providing correct amperage to the batteries?

BTW...the batteries that came with our Bighorn were junk...I removed them after the 1st trip with Trojan T-1275's. If you bookdock (dry camp) then you might consider some AGM batteries (at least 2). If you only use battery power between RV locations with power, then you should replace your existing batteries with a pair of deep cycle batteries from Costco.

11.7 is too low. Get your batteries load tested at an auto parts store or service center. If they test good, make sure all connections are clean and tight.

When on shore power, the Power Converter should be recharging the batteries. The levelup control panel should read 13.2-13.6V DC. If not, either the Converter is not supplying power, or the power is not getting through the 12V DC mini-circuit breaker near the batteries. The manual reset breaker may have tripped. In that case, look for a row of small circuit breakers covered by red rubber boot. One breaker will have a teeny tiny reset button.