nh_mark

So this morning I was supposed to take my car for its first oil change but when I went to the garage the battery was dead. I do have the battery protection package but the last time I drive the car I didn't think it was going to be sitting this long....I was wrong. I last drove the car on July 20th, 11 days ago, and that was a pretty long (120 mile) trip.

So I have 2 questions:

1. Do you guys put your battery tender on after every drive? I mean hindsight says I should have used it, right?

2. What is the reason for Corvettes being famous for this problem? I mean I understand there is a current draw someplace when the car is off but why doesn't any other car or truck that I own do this? Is the Corvette battery smaller to reduce weight or something?

thanks,
Mark

C7Joy

I think the manual suggests using the tender if it will be more than a week of inactivity. I drive mainly on weekends and have not used my tender since late spring, and all has been well. When the weather starts to change I will drive less and probably hook up after every drive, until I have to cover her up for the season.

JerryU

120 miles should have been more than enough to full charge the battery. I just left my car for 16 days while on vacation, started fine. Bought a charger 9 months ago when I got the car (the same one Chevy sells but from a lower cost source) because my battery voltage was always low, 12.4 volts after 1 day sitting. Had meter checked and it was fine. Wife's car has 4 year old battery and it reads 12.8 to 12.9 volts. Dealer said he checked the battery when I brought the car in for a software update but I doubt he removed the battery, only way to properly check. The car has started fine for 9 months. Never used the charger after first trying to see if it helped the low voltage after sitting a day - it did not.
Even after the 16 days while on vacation drove only 30 miles the first day back and as always voltage reads 14+ while charging. The next day I measured the voltage ( to eliminate measuring surface charge) the battery read 12.4 volts. It should read about 13 volts. Have checked the battery terminal connections and they are fine.
They should replace your battery free of charge. I will get a glass mat battery when this one fails. However the Delco has a large power component PC board on the left side and the top terminals will have to be in a certain position to have it fit. An Optima does not look like it will fit. We'll see if anyone offers one when I need it. Replaced my battery in my C6 after 3 years. Found a small leak when it was removed! Used an Optima in that case.
Let us know what the dealer does. There is no need to use a charger unless you'll not be using the car for over ~3 weeks.
One more note. I thought driving my street rod ~15 miles every other week would not require a charger. After two Optima batteries, replaced free, put a full time charger on and for the past 10 years have had no problems. Short drives are not enough even with a high capacity alternator.

blackmagicZ

On star activates your systems all the time. If you were to sit next to your car for 24 hours, you might here the sounds of things turning on. On star monitors your car on a regular basis. And there are other reasons for the drain too. But yes, a battery tender is a good idea.

nh_mark

Called the dealer and they said 11 days is NOT normal so I'm bringing it in tomorrow.
He said maybe a bad cell in the battery or something.
I'll let you know what they find.

-Mark

blackmagicZ

The same was with my Z06. They said bad battery and replaced it.

Glen e

Many here are getting 3 weeks to a month of inactivity and it still starts...something wrong on your car.

ta70raiii

Agree with your dealer...it should not go dead in 11 days. Hopefully it is something simple.

khoeysr

I posted a thread about my C7 going dead after 6 days. I have had it into the dealer twice with no solution. With about a month left of winter I put it on a tender and had no problem. Have had no problems since, but also must say it sits for 5 days max these days as this is the driving season.

I am thinking the only surefire cure is a Z06.

1SG_Ret

Absolutely correct. NO way a car battery should go dead in that length of time. Imagine driving your car to the airport for a business trip (long term parking) and arrive back to find it DOA.

If a car is engineered to require a battery tender if left unused for a week, then the car is not properly engineered IMO.

Glen e

Correct - GM - or any car company - can't sell a car that can't sit in an extended parking lot for at least 3 weeks. If it could not, it would make the front pages of USA Today.......think about it....

JerryU

Feel my low voltage after 1 day (12.4) might be do to a weak cell but with a sealed battery can't check. Since my car starts they won't do a thing until and if it fails. 16 days sitting while on vacation and it started fine so I will not do anything until it fails.

bob guzzy

It could be just a run of bad batteries or your not using the car enough to bring the battery up to a full charge.

These batteries like to charge slowly, when I get my new car I'm going to plug mine in every time I put it away.

After a week or two, I think the battery should be charged and ready for a long life

JerryU

For what it's worth, that is why I bought the Chevy type charger. It indicates when fully charged, if the battery can't be fully charged etc. Even after being fully charged, after sitting for a day so not influenced by a surface charge, still read 12.4 volts. If you check the voltage with nothing on be curious what you read. You can check at the alternator terminal with nothing electrical on accept the alarm and the many items on all the time anyway.

JDM111er

I received an email from On Star with the diagnostics of my vet. Since I'm storing mine over winter for 5-6 months, will I get an email when the battery is low? Thanks in advance

blackmagicZ

They may send you an email telling you your battery is dead if you don't keep it on a battery tender.

Scoobydoobydoo

My battery went dead after sitting for approx 12 days, this after taking a 100 mile cruise. Made an appt with the dealer, he changed the battery and all has been well since. Even if it sits for a week or so.

AORoads

I hope that something small is found to be wrong with OPs car and is correctable. But we will see by the mid to end of winter if this is a relatively common issue. I hope not!

WB6HRO

This has been going on for years My C5, C6, & C7 all have so many computers that in order to keep things in memory, it takes some current. That said none of them really would start if they sit longer than 2 weeks as a rule of thumb.

I always plug in my "Battery Tender" when I don't anticipate using the car again that week. It's actually easier on the battery when it is kept on the charger and it will last longer. I've been doing this for 12 years on my 2002 Z06 (traded it in on C7) and 2009 ZR1. Never come out to a dear battery.

Glen e

Maybe true on your older stuff buy not true on c7’s.....they are going a month or more and will start, due to the new "computers" not having to run when off. And current is not needed to "hold" settings. Google non volatile ram for more info.