I have a 2009 G6 GT Convertible. Over the past (9) months I've replaced the battery (3) times. Had the Alternator and battery both checked at AutoZone each time.
The Alternator would only charge 13.8. After we loaded it with Headlights (Bright) A/C on High, it finally dropped to 13.1, then dropped to 8.? after about 15 sec's.
So of course I replaced the Alternator this time. After install with new serpentine belt (which took me longer to replace the belt than the alternator because the routed it through the Front Engine Mount), the Alternator charged at 14.23. Boom... Happy Camper.
Drove it to work next day, all is fine. Go to start it after work, and it almost didn't start again. Got home, battery was at 12.47v. Alternator charging at 13.61.
Went back to AutoZone. Re-tested, and shows Voltage Regulator in the Alternator failed. Will have another one in the morning.
I've seen articles Googling the issue that show the Alternator will default to 13.8 if it looses connection to a controller ? Could that be the real issue ?
In looking for anything to draw power, the Cargo Light in the Trunk won't turn off. Maybe it does... Kind of like the Refrigerator light, you don't know...
The switch won't turn it off. So in trying to carefully remove it, I broke the tabs on the top of it off. Googled, and went to GM Parts Giant and others to find the switch.
What is it called, and where to get it ? Cargo Light Switch didn't work to Google.
Thanks in Advance for your help