Does your battery voltage fluctuate?
Thread Starter
Melting Slicks
Joined: Apr 2002
Posts: 2,439
Likes: 590
From: Tellico Plains Tennessee
Does your battery voltage fluctuate?
I have about 900 miles on my C7 Coupe. I've noticed recently that the battery voltage will fluctuate between 15.2 volts all the way down to 12.8 volts. It slowly wanders up and down, sometimes settling for a while before wandering again. If I turn on my lights, adding to the drain, the voltage settles out at about 13.4 volts and pretty much stays there. It may have always done this and I just didn't notice, what with all the news things to watch and learn about this car. The battery never seems low when starting so it must be getting sufficient charge. I've checked the cables at the alternator and at the battery but nothing is loose or seems wrong. Anyone else have/seen this situation? Is this maybe how modern charge controllers work?
Melting Slicks
Joined: Nov 2005
Posts: 2,074
Likes: 309
I asked this question about my pickup truck and a trained GM Tech says that this is normal for the newer GM vehicles. I think it's part of their strategy to try to eke out as much fuel economy as possible.
Le Mans Master
Joined: Sep 2003
Posts: 8,847
Likes: 795
From: Longview Texas
Yep. I used to think that the battery should always be charging at around 14.6 volts, and rarely go above 15V, but I have noticed the same thing on the Stingray..
Out on the high way when you know the battery should have been driven enough to be fully charged it may stay down at 12.8V, but around town I have noticed that for no apparent reason, it may start charging at 15.2V or 15.3V.
Out on the high way when you know the battery should have been driven enough to be fully charged it may stay down at 12.8V, but around town I have noticed that for no apparent reason, it may start charging at 15.2V or 15.3V.
Thread Starter
Melting Slicks
Joined: Apr 2002
Posts: 2,439
Likes: 590
From: Tellico Plains Tennessee
Yep. I used to think that the battery should always be charging at around 14.6 volts, and rarely go above 15V, but I have noticed the same thing on the Stingray..
Out on the high way when you know the battery should have been driven enough to be fully charged it may stay down at 12.8V, but around town I have noticed that for no apparent reason, it may start charging at 15.2V or 15.3V.
Out on the high way when you know the battery should have been driven enough to be fully charged it may stay down at 12.8V, but around town I have noticed that for no apparent reason, it may start charging at 15.2V or 15.3V.
I suspected there was an intelligent charge controller, similar to the ones used for solar power stations, that charge when needed rather than just pump out 14+ volts without regard for the battery's need or condition. Like the chargers we use on seldom driven cars, this charger must go into a "float" condition to monitor the battery and electrical requirements. Thanks and drive safely!
