Hello, I have an issue with my 2006 grand prix 3.8L V6. Often times I get a message saying "battery save mode" and my fan turns off and I just turn the knob off/on again Im good. Lately, my headlights flicker from dim to bright. I pulled into a gas station, put it in park, then I clicked the unlock buttons for the doors and then it says "charging system failure". All my grounds are solid and clean, and the battery posts are tight. I checked the battery and Im getting 12 volts. Started the car, and tested the hot on the alternator and Im getting 14.2 volts so thats good. I also took the alternator up to advance auto and they tested it twice and passed both times. They told me to unplug the 2 wire pig-tail cable on the alternator and just do a key-on without starting the car and should get 12 volts. Is this correct? Cuz Im only getting 0.95 volts. Please help, I cant figure this sucker out.

Scott