I have an 08 acadia. I drove to town and ate at a restaurant. Left there to come home, but had to stop and get gas. Stopped pumped gas. Started back up and about halfway home service charging system popped up on the dash. The volts were still showing what Id estimate to be 14 on the gauge. I was about 15 miles from home so I just drove on home. I immediately got my multimeter. Battery shows 12.68 volts. I fired the car up and the volts go up to 13.8 volts and hovered between 13.8 and 14.2 volts. So the battery is showing good and the alternator is showing its charging. I even hooked up my obd reader and looked at live data and it showed 14.0-14.2 volts when running. The service charging system light is still on, but all voltages should be good. It fires right up no hesitation. I went ahead and stuck a battery charger on the battery just to top it off and see if it changed anything, but is there anything else that could cause that light to come on? Thanks for any help.