House charging system issue

[gr8rcfan]

Batteries at 9.6v at all times ( even w/110 AC hooked up, or engine running)
Water levels good

Sequence of events:
Parked but failed to hook up land line for 2 weeks.
2 weeks later, found no 12V lights, so attached AC and got them back
1 week later, doing scheduled generator/HVAC test. Generator wont start. Checked house battery voltage and water levels.

Question:
Shouldn't I get charging voltage (13v+) at the batteries when AC is plugged in or the engine is running?

[Trophy1200]

Is your use/store switch set to use?

[gr8rcfan]

Originally Posted by Trophy1200

Is your use/store switch set to use?

It's a momentary On switch that is supposed to reverse a relay when depressed. But the indicator remains on when shore power is applied. And the indicator remains off when shore power is removed. So I've always felt unable to determine if its on or off

But I never hear a relay when I depress it under any situation

[Chateau_Nomad]

At 9.6volts... batteries are possibly toast... history. I'd get your store/use disconnect switch resolved before buying new batteries.

[JimOIB]

It appears you have a battery with a shorted cell - 9.6 volts is never good.

An undervoltage situation like yours can cause things not to work even though you think they should. You might not get a charging voltage from the converter or when the engine is running. Built it safety protection that isn’t always documented.

If you have two coach batteries then disconnect them from each other and see if one reads above 11.9 volts. If so then try hooking just it up and see what happens. If not 11.9 or above then the battery is dead.