BATTERY LIGHT COMES ON RANDOMLY. CAR SHOWS NO SYMPTHOMS. LIGHT STAYS ON FOR COUPLE OF MINUTES THEN GOES OFF THEN ON AGAIN HALF-HOUR LATER. CAR RUNS GREAT!
HAVE CHANGED CORRODED BATTERY CONNECTOR AND REPLACED BATTERY. NORMAL ALTERNOR VOLTAGE IS 14.5. WHEN LIGHT IS ON IT IS 13.9.
Check the connectors on the alternator, make sure all are clean, I had an issue where one single wire push-on connector was dirty, kept giving me and intermittent battery light, cleaned it up, no probs. Hopefully this will help.