Turbodude

I have a 2006 C6 Coupe with 62,000 miles on it.

Since April this year the battery will not hold a charge. I may not drive the car for 3-5 days at a time...weeks if I leave it at the airport..which I'm now unwilling to do. I've had 3 batteries installed since then. Some techs have measured a current draw with everything switched off but have been unable to isoloate it. One tech blamed it on the OEM radio/CD player trying to eject a nonexistent CD every 3 minutes even with the car unoccupied. So I replaced the audio system, but the problem persists. The latest GM tech suggests I disconnect the battery when not in use.

Is this the best that can be done? Disconnecting the battery?

I'd be grateful for any suggestions how to fix this.

BTW...my battery disconnect switch arrives on Friday.

Knob Jockey

After the car has been off for around 20 minutes everything goes to 'sleep'.

That's when you check the DC current draw and if it is above the GM spec., then you have a problem that needs to be addressed.

If you have to leave the car parked for weeks and are unable to connect a battery tender, then your best option is to disconnect it.

In your situation involving airports, you may get a bit longer life out of the battery if you buy a 'deep-cycle' battery (like an Optima Yellow Top).

glenB

GM says the battery will go dead within 7-10 days if left unattended due to normal parasitic draw.

Don-Vette

QUOTE:......."The latest GM tech suggests I disconnect the battery when not in use."


Really? Wow, some tech. LMAO

The electrical path of all electrical systems in the world are written in schematic drawings,test the circuits,isolate the problem,fix the problem.

CO Lightfoot

Find out what is killing your battery.

Might be a problem with the car... crimped/damaged wires under the seat, especially if you move the seat forward & back every time you enter and exit. Or something else causing excessive parasitic drain. Or corroded battery clamp. Or damage to the starter-battery connection post. Or faulty alternator, etc etc etc.

Or maybe your C6 is perfectly healthy. But the C6 is factory-equipped with a smallish battery & alternator... infrequent use and mostly short trips will drain the battery, which leads to a short life.

Regular use of a good battery maintainer (CTEK, Battery Tender, etc) will keep your battery well-charged. But it might mask an underlying problem -- which is why you should find out what is killing your battery.

AORoads

All of the above is correct, incl. and especially the one underlined. The only thing I might add is a poor ground somewhere in the system which may have some effect on the electrical system. You probably need to find a better "electrical system detective."

c54u

From page 364 of 2007 Corvette manual.

Vehicle Storage

If you are not going to drive your vehicle for 25
days or more, remove the black, negative (-) cable
from the battery. This will help keep your battery
from running down.

c54u

I am leaning towards a bad alternator....it just is not providing enough charge to your battery.

OP, did you have your alternator tested?

AORoads

good point on alternator, but one would think that some technician checking for constant dead batts. would do that check. then again, that's an "assumption" on my part.

Wayne O

Only 7 to 10 days....that's a sad commentary. I've never had any starting/battery issues with my 2005 but the longest the car sat idle was about a month. What's sad is the problem seems so random....the battery on one car dies in a few days while the next car off-the-line doesn't experience the same problem. I think GM's recommendation to disconnect the battery is their admission they can't or won't fix the problem. Many other brands of cars have similar technology and they don't seem to be afflicted with the same battery problem.

LSD 2005

vetdude

My bought-it-new '06 Z06 cannot sit off the Battery Tender for more than 3 days. My wife's '06 C6 convertible cannot sit off the Battery Tender for more than 2 weeks without bing started. Both car hav had their battries replaced. Read somewhere on here, TSB or member comments, parasitic battery drain can be attributable to electronics in the lock mechanism in the passenger door. The very experienced Tech at the dealership's service department said that it could be a cause but he couldn't guarantee it would fix the battery drain problem.

I noticed the newer Corvettes (2012-2013) are now available with a "Battery Protection" option from the factory. Who knew?

Thanks GM.

pfic06

I have a 06 with similar issues. I highly recommend Install a Piority Start. When battery drops below 12v. It disconnects the battery. To reconnect, simply push in the cigar lighter. Priority Start sees the change and reconnects the battery. I have used it several times and it works. The only recovery action is to reindex the windows.

cclive

The battery disconnect switch will make it so that you can take the car to the airport if you want. Be careful though that you know how to use the metal key to open the trunk and then pull the cable to open the door...the fob will be useless after you disconnect the battery. Ultimately though, you need to get the car fixed. Same goes for Vetdude...something is wrong with the car if it will not go three days when parked. This is a very short time so the battery drain must be large and obvious. When looking for problems in any system, the bigger and more obvious problems are usually the easier ones to find and fix. It's the small, marginal problems that are more difficult to deal with.

My car draws between 11 and 17 milliamps from the battery after everything settles down. At this rate the battery loses about one amp-hour every three days. Car batteries are normally not rated in these terms, but 60 to 80 amp hours is the range that car batteries fit into. The battery should still be able to easily start the car when it has lost 25% of its' capacity, so a normal C6 should be able to go weeks parked and still start. This would certainly not be good for the battery, but it would work. Lead acid car batteries like to be stored fully charged. As an aside, lithium ion batteries (laptops, cellphones) like to be stored at 50% of full charge.

Bill Dearborn

Typically you can let the car sit for over 4 weeks without issue if you have a good battery. My 08Z battery lasted 4.5 years and would hold a charge for 4 weeks in a cold garage during the winter. Battery worked fine until it didn't and then it wouldn't hold a charge for more than a few minutes.

Not sure what battery you have in your car but if its the original battery it may be time to replace it as you are near the end of its life cycle.

With a current draw of less than 20 ma after the BCM puts the car to sleep a 600 amp hour battery will last one hell of a long time before it gets to low to start the car. A new one would probably last upwards of 10 weeks in warm temperature environment. In a low temp environment the charge would last about half of that.

Bill

CO Lightfoot

That option is a separate-item CTEK 3300 battery maintainer with Corvette logo and cig adapter. It's not a built-in device.

And you don't have to buy a C6 to get one... it's a $110 accessory you can buy from any Chevy dealer.

Last I checked, it's $77 from GMPartsHouse.com: http://forums.corvetteforum.com/1576496258-post9.html





Or save a few bucks and buy a plain-jane CTEK 3300.

RnLi

I'll just add.....

My "08 Coupe, with the original battery, was just started after sitting in a garage, with no charging devise, for 27 days. Went starting it didn't even "grunt".

On this day, I drove it well over 100 miles at Interstate speeds. MOST of my use is like this and I believe, as others have suggested, this type of driving contributes greatly to battery longevity.

After mentioning this, I'm thinking I should get the battery tested because it is 5 years old

EDIT>>..and I should mention to the OP.....there are several "maintainer" type charges that work from solar panels. These would be ideal for airport parking. But you do need to resolve if and what the problem is first.

cclive

Bill, maybe drop a zero off the 600...that's more like the size of a golf cart battery...car batteries go from about 45 for a very small one to 120 for a very large one.

Gearhead Jim

Wayne said it right; it's so annoying that the problem is completely random.
We had a 2006 3LT, so it had all the fancy dodads. We let it sit for a week many times, and two weeks once or twice, and it always started perfectly.

Turbodude

I've just ordered a Priority Start from Amazon.

This is the easiest fix for me, as I park the C6 outside...my garage is full of metalworking tools/machines. I'd rather not run an extension cable outside the house for the CTEK.

The CTEK looks like a great solution for a car parked inside.

Thank you everyone for the excellent feedback and advice.

Merry Christmas to all!