No charge at battery

Lets start from the beginning. What was the problem you are observing.
Was it that the ammeter shows discharge when the car is running?
Unfortunately, as I said once before, the ammeter is corroded to pieces, needle is not going to stay in place. The two wires that connected to the ammeter are currently spliced together, and have been since I had my hands on the Duster.
The reason I believe there to be an issue is because I just happened to check the battery voltage while running and noticed it was lower than the expected 13-14 V range, 12.4 volts. I know that at some point the battery had been getting charge before.
But, perhaps I am looking to far into this, just giving myself trouble. I am just the kind of guy that wants things working, rather than having to put the battery on a charger after every time I run it.