"service Charging System Soon" Question..

[Chevygm]

So I just picked up my 2010 Tahoe LTZ last week. Its been fine since I purchased it.
Today I was in a drive-thru and the "Service Charging System Soon" poped up on the DIC and the Battery light came on as well, the voltage gauge when I start the car went to 14,5-15v, the dropped down the 14, then to 12... So I went to get the Starter/Alternator and battery checked and it all came back okay. It did it like 1-2 more times..again the gauge is fluxuating. I turn it off for like 10 mins and it stays at 14v... The car doesn't die, nothing seems to act weird...I'm not used to cars with new technology so any insight would be appreciated. This just started happening today..Im thinking alternator or battery..maybe even the 175amp fuse on the terminal..

 

[robgreg75]

Mine did that too last fall, it started with seemly too high of voltage to then no charge at all. There is a connector of the passenger side of the engine bay that you can disconnect and it kills the voltage variation, for economy the alternator isn't working all the time disconnecting this makes it on all the time. I unplugged mine for a while and it seemed to fix the issue then it started acting funny again and I plugged it back in and has been all good for like 5-6 months. So I didn't even change anything.

 

[Chevygm]

Mine did that too last fall, it started with seemly too high of voltage to then no charge at all. There is a connector of the passenger side of the engine bay that you can disconnect and it kills the voltage variation, for economy the alternator isn't working all the time disconnecting this makes it on all the time. I unplugged mine for a while and it seemed to fix the issue then it started acting funny again and I plugged it back in and has been all good for like 5-6 months. So I didn't even change anything.

Im still new to these vehicles..so far its been great..just learned about the ECU regulation of the alternator..what does the connector look like? Thanks for the reply.

 

[robgreg75]

It is a small connector near the battery/a/c lines. I don't remember exactly but I think there was a thread on here with a picture.