My new 2006 Roadster has been sitting in the garage for 8 days because of the 100+ degree weather here. This morning it was 74 degrees so I head for the roadster but, it was not to be. I found a totally dead battery. I searched the forum to confirm the likely cause was the trunk lid was not slammed shut. There is so little difference visually between shut and latched and completely shut it is way to easy to kill the battery.
As a result of Katrina all my essential car supplies like jumper cables and battery chargers were destroyed under 10 ft. of salt water and mud. So I was off to Wal-Mart for some cables. No luck with that as the one I picked up could not start the car. Lights and everything would work but, just a click, click, click of the solenoid when trying to start it. I figured the cables were to light weight for the high compression engine? I went back to Wal-Mart for heavier cables buy, was distracted by a "Rapid Charge" 6-4-2 automatic charger at about the same price for heavy cables. I left it connected for 3 hours with no indication of progress. So, it's off to Sams Club where I found a 25-10-2 amp automatic charger with a 75 amp starting feature at $49. I decided to try the charge instead of trying the start feature first. After three hours it has dropped from 25 amps into the 2nd stage at 12 amps so it looks like I might get to go for a cruise today after all.

My Question is, This battery was down to flat dead. Has anyone had any experience reviving a new battery or knows if this battery will be reliable after sitting for a week completely discharged with a load applied? The "load" is either the trunk light or as suggested the power top circuit constantly checking to see if the trunk is closed.

Thank You in advance for any information
Larry Hegle
2006 Aero Blue Ltd. Roadster
Automatic 900 miles

 

When mine died no amount of charging and or jumping would get the car to start. I ended up buying a new battery. Course mine was 2 years old.

 

Ditto on my Ltd battery, just before trade-in.

 

I've been told that once a battery is completely drained it has lost half of it's life. My experience with aircraft batteries tends to support this. Check your electrolyte level and charge the battery fully. If it still won't start your car or when it begins to bog down when starting then get a new one. You can also test your battery's condition with a load meter.

Little navy story that I've been told...

Submarine commanders when they are running on their sub batteries will not let the batteries drop below 50% power. They don't care if they are in a middle of a fleet exercise - they will surface and charge their batteries.

OK, I don't know if it's really true or not but at least the story livens up this post.

 

i have a lot of experience with lead acid batteries.
charge it up as best you can with a good charger.
if it is a fairly new battery, then it hasn't had a lot
of time to sulfate.
charge it but don't let it overheat, if it is too hot to touch,
then let it cool down then charge it some more.
charge it till the ammeter shows a low current level.
lead acid batteries hate being discharged completely.
my other car has the battery it came with 7 and 1/2 years
ago and has been discharged similar to your description.
if it charges up to a low current draw level and will start your
car easily, then don't worry about it.
if it has been discharged a while, it may take a while before
it draws any current to speak of when charging
if it won't hold a charge, then it's time to get a new one.
make sure something in the car isn't pulling it down.
if it takes a day to charge it don't worry.
just get it charged up again as soon as possible.

 

Thanks for all the information on the battery. As it stands now the charger fully charged the battery and it started right up. The charger got hot but the battery did not. It is a original battery on a new 2006 put into service 5/18/07. How new is that? It is under warranty anyway although it might be easier to just buy one if I knew what battery would fit that tight spot.
I do not know if the trunk light stays on when it is not slammed shut but latched, I was under the impression it would turn off after 15 minutes anyway. The other information I found on this forum was that the power top circuit was constantly checking the trunk because it was open as far as the power top was concerned. I know for a fact the top will not work if the trunk is not closed TIGHT. It seems odd to me that it would constantly check with the ignition off and the key removed.
I have had the car for three months and the only two factors I can see here are that the trunk was not tightly latched and the length of time since I last started it (8 days). It has gone 3 to 4 days between use without a problem. I guess time will tell if it holds a charge. If it does run down I wonder if it will set any codes to indicate the problem?

Larry Hegle
2006 Aero Blue Ltd. Roadster
Automatic 900 miles

 

Interstate makes the exact same battery for this car right down to the same decals. If you do a search on this site or the other one I listed the part number when I changed mine in the '04. I don't have the number here now.

 

Try the 2 amp setting on the charger. It may take as long as THREE or FOUR days to bring a good battery up to full charge.

 

Same thing happened to me, the trunk wasn't shut tight, battery was totally dead. I put the charger on for about 24 hours and its been fine ever since.