electrical

today I noticed under my motorhome that I seen some loose wires and one wire that was not connected, on the inside at the panel were you can check your water level, none of the light would light up the last time I used the camper they worked, the inverter do I need to turn of the power to these wires before I attempt to join them together, what is the inverter for , I am not a electrician, so any advise I would appreciate it. motorhome is a freedom elite 29 fe, these wire are locate right a the black/gray water drain