My Power point in the dash is on the ignition circuit. Low voltage most likely from poor connection or not a good ground.
My previous (1990) Mh also had power points behind the front and rear TV's, and at the dinette, all on the Aux (Coach) battery.
Hooligan, Pensacola, Fl -U.S. Coast Guard 1956-1985
2016 Thor Siesta Sprinter 24ST diesel -1972 Moto Guzzi
2008 Suzuki Grand Vitara TOAD