OK just had the alternator and battery tested by ATS.
ALT: Volt 14.26v, ripple too big....
Batt: 12.6v; start capacity 82%
Does ripple shed any light on what the specific problem is?
I believe that means the regulator / rectifier is not converting all the AC current to DC current that cars run on - car components don't like AC current.
Please wait for another reply before condemning the alternator