Faded lights. Nav, bridge etc

[Wardy549]

last night as I was pulling into port all of my lights started slowly getting dimmer and dimmer and then off completely.
Does that mean my alernator is shot?
I have twin 454’s and the starboard motor’s volt guage I noticed was reading less then 12 vs port engine 13/14
So im hoping all this means the alternator took a crap!
Thanks !!

 

[Captn TJ]

How about corrosion on the battery terminals or leads from the alternator?? Guess I'd start with a digital volt meter to see what the output is.