1994 Damon Ultrasport Class C - Battery won't charge

Follow the wires from the batteries to the converter if you can. It may be a challenge but a well engineered coach should not put the converter far from the batteries because of the long resistance from cable runs.

If you are able to follow the wires you should find it. Near fuse panels, under table seats, are obvious places. Also look for a "mysterious vent panel" because converters most often have cooling fans.