The one solenoid I can see would be the isolation one, with the wire going to the house batteries coming out one side of it. I get "alternator charging" with the engine running and not when the engine is off.
ISTR a test where I had a voltmeter on the engine battery during starting. Voltage first fell to 11.x then jumped to 14.x. So I will do that with the house batteries, which should answer my question, I hope. Plan is to turn the key very slowly watching house battery voltage. (with multimeter, not Trimetric, which has a smoothing delay to it.)
I should also be able to do something at the solenoid itself with the voltmeter and possibly hear something.
Will report later today.
