2009 travese LTZ, alternator went out... so I thought. Alternator was not charging on dash volt meter. Replaced alternator and a week later ended up with dead battery. Replaced battery and 3 days later while I was driving notice service charging system warning came back on. Watched volt meter and only had about 12 volts. While still running i disconnected battery and confirmed alternator not charging as the car died. After I connected battery ground the problem went away. Volt meter reading just above 14 and warning message gone. Drove car for a few more days and again service charging system light came back on, pulled over and again disconnected ground on battery, same result. Everything is back to normal , charging above 14 and no warning lights. What could be causing this issue with the alternator that disconnecting the battery ground wire would "reset " this issue.