One more hint. Its always worth glancing at the ammeter. It will indicate how much current is flowing to or from the battery.
I don't know the history of why many are labelled 'alternator'. That can be misleading. Sure was to me.
As you can see in the above diagrams,the ammeter is located between the battery and the main junction. So it only indicates how much current is flowing to or from the battery to the main junction. Probably won't be much help with this problem, but its worth knowing about.