when i bought my rv last sept, i was unaware of the solar panels on roof, the po never mentioned it. after driving back and climbed to top, oh, bp solar panels!! in next few weeks my coach batteries were always dead at outdoor storage after fully charged. i dug into it and found the culprit - "SolarPro" controller was cooked (the manufacturer has long been out of businee). bought a new 20a mppt from ebay and installed, 8a charging were seen on a regular day; my batteries are always full at 13.2-13.7v now. according to po, the panels were installed in 2002 (11 years already by now), he didn't list it as a feature due to the fact it was not working
did you double check your controller? you can simulate the input with a car batt charger and a batt/12v light bulb as a load (pm me if you are not sure). although it seems like your controller is working per your description, just to make sure it is working consistently. the panels rarely fail unless broken. if the controller proves to be good, i would check wire connections the next. good luck in fixing it.