Simple.
No worries, it's a relatively small issue.
Judging by your question i would surely say that the fault lies in your alternator.
It's a '96 meaning to say that the alternator has either been changed once or not at all.
1. Get your alternator check or replaced if necessary.
2. If cost is the issue get it refurbish.
Do not be fooled by the mechanic if they says its no serviceable.
Open the alternator up and have the coils and contact points cleaned. Preferably a solvent base cleaner.
All alternators has this "magnet" ring to it. Through the years it might have lost it's conductivity. This "magnet" MUST be replaced.
As for the coils and connecting points, it can be cleaned of of it's carbon and dirt deposits.
P.S From where i come from, its more cost effective in servicng the alternator than buying a new one.
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