2017 Four Winds 28Z. On shore power all is fine and control panel lights accurate. On battery power all systems work but when main interior lights are on control panel lights are inaccurate and if you turn on water pump the main interior lights dim or go out. Turn off all power usages and control panel reads correctly. Suggestions what to look for?
Has your 12v battery bank ever run down very low before you had the chance to charge it back up ? What is your normal charging practice, do you keep your rig plugged into shore power or do you charge it periodically when you think it's needed ?
I agree use a volt meter. It sounds like it might be a battery situation.
Use a voltmeter to check house batteries output voltage. Could be a loose battery cable or battery replacement if voltage is low. Start engine and check house battery with voltmeter again to make sure the battery is being charged with engine running - also the house lights should be bright while engine is running and control panel lights are accurate.
