House battery not reading in control panel

[crossle32]

I have a 2003 HR Scepter. At the control panel, when I push for a reading on LCD for the “house battery” voltage, the LCD stays blank.After ringing out the wires on the switch, the house battery wire feeding the switch only reads 6V.The house batteries are giving 12.6V at the battery anywhere in the compartment.The chassis battery reads fine at the panel.Does anyone here have any suggestions where to start?TIA

[Unplanned Tourist]

Sounds like there is a bad connection somewhere. Use a test light to check all the places you can get to for power. (More load)
A digital VOM draws so little load that it won't pick up a poor connection.
Hope that helps. Others may join in with experience on a rig like yours.
Happy Glamping.