Jaydubgt

I don't know how many of you use a Battery Tender trickle charger, but I have a question concerning mine.

I have owned my 2013 GS M6 15k miles for about a month now. When I first bought the car, I was driving it daily. I was off of work, due to the devastating fires here in northern Cal. Our company was closed for about 3 weeks, which gave me a good chance to get to know my new purchase.

Now that I'm back to work, it's been relegated to a weekend car. The first week, I didn't hookup any battery charger at all. It started fine that next weekend.

Just to be on the safe side, I decided to hook it up to a Battery Tender that I'd had for about a year.

If everything is working, a red LED will be on as it's charging. Once it gets to about 80% of full charge, the LED color changes to green.

Well after having the car on the battery tender hooked up for 3 days the red LED is still on. I guess that means it hasn't reached 80% full charge. That time seems excessively long. The car starts right up, just like it did when I left it for a week without a charger of any kind.

So, you Battery Tender users, is it normal for the green LED (80% fully charged) NOT to come on after 3 days straight of recharging? Even though the car starts right up?

I don't know how old the battery is.

Does that make sense?

Thanks in advance for any help you can provide.

jdvann

Most mine has stayed red is about 24 hours, that was after detailing the car and having the doors open and top up and down a few times over a 8 hour period. A battery test may be in order...

btw...I have a Battery Tender+

Corvette_Ed

Welker1

+1

danzio56

I too run a Battery Tender Plus on my '10 GS. It never takes more than 12 hours to reach maintenance mode (solid green). If I've had it out detailing or whatever and put it in the barn, it is always solid green by morning.

So yes, a battery test should be done.

J.Moore

Could be the battery or the age old excessive parasitic draw problem C6's sometimes have. If you have a draw more than about .020-.030 that could be why it takes so long to charge. Actually it would take more than that, probably closer to .100ma or more.

My old 05 C6 shuts down in stages. First 10 minutes or so after engine shutdown it will show .980ma, almost a full amp. About 5 minutes later it drops to .180ma, then after about 20 minutes total it drops to .020ma.

This morning my battery showed 12.58 volts after sitting for 7 days without driving, starting, or being charged. Not really low but I connected my tender anyway and it took 5 hours to fully charge to 14.70v and the green light pulsing indicating full charge and that is with .020ma draw which is normal.

And my Schumacher charger/tender is only a 1.5 amp charger. So if you have a parasitic draw of an amp or more a small tender is struggling to overcome this draw.

Ward Cleaver

I would say a new battery may be in order.

Regards,
-Ward

flyeri

I let our 2011 GS sit for about 3 weeks without connecting my Battery Minder. It took 2 days to go into maintenance mode. Since you are on day 3 after sitting for a week I would have the battery tested. It may simply have a weak cell.

spuddeamore

As everyone has said, check your battery health...a load test. If it checks out okay, you probably have a current draw that the battery tender cannot overcome. It only charges at around an Amp and a half at most.

Judgebull

I agree with others I think your battery is nearing the end of its reliable service life and should be replaced. I have 13 GS with the original battery. I use a CTEK charge maintainer 7002 and hook it up whenever the car is not in use. Sometimes it goes automatically going thru the plate reconditioning cycle. The key is to keep it on the maintainer when not in use.

FortMorganAl

And one more vote for weak battery. I just bought another vehicle and it started but seemed weak. Put a Battery Tender on it for 36 hours and no green. Still started quickly but the first crank over still seemed weak. Voltage indicated full charge. Replaced battery. No more issue.

mikeCsix

My 2012 battery is still going strong after an 18 month storage fiasco. The small wall mounted Battery Tender will only produce at most 3/4 of an amp, so a large 100 amp-hour battery is going to take awhile. If your battery doesn’t have internally shorted plates and there is nothing wrong with your charger, it’ll get the job done, and it will do it more quickly if it is disconnected from the car.

I highly recommend getting an inexpensive volt-ohm meter so you can see what is going on with your system. There must be tons of YouTube videos about how to use them, and you’ll have a meter for troubleshooting other problems.

ByRiver

Check your Harbor Freight coupons. There is usually one for a free volt meter with any purchase. I now have four volt meters and close to 20 tape measures.

Don-Vette

Time for a new battery IMO,it's almost 5 years old.

blittle

I agree with all the above....I have a 12 GS on a battery tender and the most I have ever seen it on red was about 24hours.

Jaydubgt

Thanks, guys.

I'll have the battery tested/replaced.

Unfortunately, the car came with no records, so I don't know how old the battery is. It might be the original one, but I can't be sure.

Which is another reason I should have it checked.

Thanks, again.