Or it may just be that your power converter/charger is not working. A quick check with a voltmeter at the battery(s) will tell you. Should be around 13.6v when plugged in and charging. You should also check the water in the cells - if it gets too low they won't charge or produce power. Add distilled water as needed.
Last, if you have a battery disconnect switch, in most RVs it needs to be left ON for charging to work.
2004 American Tradition; 2014 Buick LaCRosse
Homebase in the Ocala Nat'l Forest near Ocala, FL