If it's DBS make sure the re-flash was done.
Dead Battery?
Thread Starter
Intermediate
Joined: Aug 2006
Posts: 49
Likes: 0
Dead Battery?
Just bought a used C6, 2005, 6speed manual. The battery has died 3 times in the last week. I DO leave the car in reverse and take the key and fob out of the car. Have checked the battery and alternator, both are good.Anyone alse had this problem, or have any ideas? Thanks for any advice!
Advanced
Joined: Dec 2007
Posts: 54
Likes: 0
From: Decatur GA
When my 05 original battery was crapping out, it would get down to 10v but after a drive it would get back up to 12.5v after the alternator charged it up obviously, it just wasn't holding the charge. I took it to Autozone because I figured the battery was on its way out as they can test the battery etc, they said it was fine and so was the charging system in my Vette. I didn't trust that result entirely because it was the original battery, 3 years old and I have read on here that Vettes eat batteries. I replaced it and everything was fine from then on.
Team Owner
Joined: Dec 2003
Posts: 57,408
Likes: 164
From: queensbury ny
Could be DEAD BATTERY SYNDROME OR JUST AN OLD BATTERY.Get yourself a BATTERY TENDER in any case and hook it up.Real simple plug and play unit.It will save you from this headache.OEM batteries are about a 2-3 year life span.
Racer
Joined: Apr 2007
Posts: 393
Likes: 0
From: Austin Texas
Just bought a used C6, 2005, 6speed manual. The battery has died 3 times in the last week. I DO leave the car in reverse and take the key and fob out of the car. Have checked the battery and alternator, both are good.Anyone ales had this problem, or have any ideas? Thanks for any advice!
There are 44 "DBS" threads in the C6 section.
Additionally, there are 101 "dead battery" threads in the C6 section.
The early C6s have a problem with how they handle the electrical circuitry during shutdown. The firmware in the BCM (Body Control Module) has a flaw that creates a "draw-down" on the battery that results in a dead battery. There is a BCM "flash" that is available through the dealer or a good corvette shop, that will eliminate this battery draw-down.
Every time a (normal) lead-acid battery goes dead, it looses "some" ability to take a full charge. Since yours has gone dead at least three times, I would replace it with a new Optima Redtop. The Optima Yellowtop is NOT intended to be a starting battery. It is intended to power accessories, and cannot handle the huge current draw needed during startup. (Interstate Battery: 1-888-772-3600)
Good luck.
Last edited by Rainmaker; Jul 26, 2008 at 12:45 PM.
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Burning Brakes
Joined: Sep 2004
Posts: 860
Likes: 2
From: Naples. FL.
Just so you know you're not alone:
There are 44 "DBS" threads in the C6 section.
Additionally, there are 101 "dead battery" threads in the C6 section.
The early C6s have a problem with how they handle the electrical circuitry during shutdown. The firmware in the BCM (Body Control Module) has a flaw that creates a "draw-down" on the battery that results in a dead battery. There is a BCM "flash" that is available through the dealer or a good corvette shop, that will eliminate this battery draw-down.
Every time a (normal) lead-acid battery goes dead, it looses "some" ability to take a full charge. Since yours has gone dead at least three times, I would replace it with a new Optima Redtop. The Optima Yellowtop is NOT intended to be a starting battery. It is intended to power accessories, and cannot handle the huge current draw needed during startup. (Interstate Battery: 1-888-772-3600)
Good luck.
There are 44 "DBS" threads in the C6 section.
Additionally, there are 101 "dead battery" threads in the C6 section.
The early C6s have a problem with how they handle the electrical circuitry during shutdown. The firmware in the BCM (Body Control Module) has a flaw that creates a "draw-down" on the battery that results in a dead battery. There is a BCM "flash" that is available through the dealer or a good corvette shop, that will eliminate this battery draw-down.
Every time a (normal) lead-acid battery goes dead, it looses "some" ability to take a full charge. Since yours has gone dead at least three times, I would replace it with a new Optima Redtop. The Optima Yellowtop is NOT intended to be a starting battery. It is intended to power accessories, and cannot handle the huge current draw needed during startup. (Interstate Battery: 1-888-772-3600)
Good luck.
I'm probably pushing my luck here....original battery for 3 years and 7 months with one DBS about 18 months ago..works fine at present, running between 13.7 and 14.2 and is stored in a hot garage...was actually thinking about a yellow top, as opposed to a red top, but have not read anywhere your comments that the yellowtop cannot handle "huge" current?? In fact Bugman whom I greatly respect his knowledge swears by the yellowtop, perhaps you could explain this to me......
Racer
Joined: Apr 2007
Posts: 393
Likes: 0
From: Austin Texas
I'm probably pushing my luck here....original battery for 3 years and 7 months with one DBS about 18 months ago..works fine at present, running between 13.7 and 14.2 and is stored in a hot garage...was actually thinking about a yellow top, as opposed to a red top, but have not read anywhere your comments that the yellowtop cannot handle "huge" current?? In fact Bugman whom I greatly respect his knowledge swears by the yellowtop, perhaps you could explain this to me......
The Bugman has a lot of great info. I am not going to dispute what he says. I am merely stating what customer service at Interstate Battery (1-888-772-3600) told me. If you get a different answer, please let me know. Thank you.
Team Owner
Joined: Feb 2000
Posts: 53,520
Likes: 77
From: Arizona
I'm probably pushing my luck here....original battery for 3 years and 7 months with one DBS about 18 months ago..works fine at present, running between 13.7 and 14.2 and is stored in a hot garage...was actually thinking about a yellow top, as opposed to a red top, but have not read anywhere your comments that the yellowtop cannot handle "huge" current?? In fact Bugman whom I greatly respect his knowledge swears by the yellowtop, perhaps you could explain this to me..
Why go with a deep cycle battery if you don't need to?
Melting Slicks
Joined: Nov 2004
Posts: 2,285
Likes: 0
From: Denver PA
St. Jude Donor '07
I had the same thing. Had the battery replaced and still went dead. I bought a Priority Start and attached it to the battery. sometimes it still draws on the battery and the doors won't open. I then use the key to access the trunk area and open the door. I push in the Cig lighter and it comes back to life. The Priority Start cuts off the circuit when it draws the battery to 12.5 volts or something like that. At least the battery is not dead.
Le Mans Master
Joined: Aug 2004
Posts: 6,412
Likes: 1,295
From: Bluffton, SC
The bottom line is that, if you have a 2005 MN6 car, you really should check to see if the BCM reflash was done. If it wasn't, have it done.
If your battery has discharged completely, it's likely to be damaged at this point and a new battery will be needed.
If the car is stored for over two or three weeks in a row without being driven, a battery tender is highly recommended.
If your battery has discharged completely, it's likely to be damaged at this point and a new battery will be needed.
If the car is stored for over two or three weeks in a row without being driven, a battery tender is highly recommended.
Team Owner
Joined: Feb 2000
Posts: 53,520
Likes: 77
From: Arizona
I had the same thing. Had the battery replaced and still went dead. I bought a Priority Start and attached it to the battery. sometimes it still draws on the battery and the doors won't open. I then use the key to access the trunk area and open the door. I push in the Cig lighter and it comes back to life. The Priority Start cuts off the circuit when it draws the battery to 12.5 volts or something like that. At least the battery is not dead.
Advanced
Joined: Mar 2005
Posts: 87
Likes: 1
Bad Battery
I have a 2005 coupe and my battery just died last week. 
The dealership where I brought it charged close to $245 for the new battery and $50 each to reprogram my 2 FOBS-$345 in all! I asked a good friend who has a repair shop if that was too much, and he said that is pretty much the going rate. It only takes a few minutes to reprogram the FOBS, but you are paying for the expertise. I would have had my friend do it, but he claims he can not even get the battery because he is not a Vet shop. Then a day after I got the battery, my passenger side window would not come up. I brought it back assuming something was touched when they were working on my battery, but the dealership claimed it was a bad electric switch and charged me close to $200 for that! They tried to charge me over $300, 
but I balked, and magically the price was reduced. I just do not trust these dealerships. Does anyone think repair shops actually sabatoge your car so you have to return with more work for them? I have noticed that a lot with many dealerships. I fix one thing, and another thing is wrong the next day! My car could go for a year or more with nothing wrong, and suddenly 2 things go wrong, one after another!
The dealership where I brought it charged close to $245 for the new battery and $50 each to reprogram my 2 FOBS-$345 in all! I asked a good friend who has a repair shop if that was too much, and he said that is pretty much the going rate. It only takes a few minutes to reprogram the FOBS, but you are paying for the expertise. I would have had my friend do it, but he claims he can not even get the battery because he is not a Vet shop. Then a day after I got the battery, my passenger side window would not come up. I brought it back assuming something was touched when they were working on my battery, but the dealership claimed it was a bad electric switch and charged me close to $200 for that! They tried to charge me over $300, but I balked, and magically the price was reduced. I just do not trust these dealerships. Does anyone think repair shops actually sabatoge your car so you have to return with more work for them? I have noticed that a lot with many dealerships. I fix one thing, and another thing is wrong the next day! My car could go for a year or more with nothing wrong, and suddenly 2 things go wrong, one after another!
Pro
Joined: Sep 2004
Posts: 638
Likes: 2
From: Medford NY
St. Jude Donor '05-'07
I have a 2005 coupe and my battery just died last week. The dealership where I brought it charged close to $245 for the new battery and $50 each to reprogram my 2 FOBS-$345 in all! I asked a good friend who has a repair shop if that was too much, and he said that is pretty much the going rate. It only takes a few minutes to reprogram the FOBS, but you are paying for the expertise. I would have had my friend do it, but he claims he can not even get the battery because he is not a Vet shop. Then a day after I got the battery, my passenger side window would not come up. I brought it back assuming something was touched when they were working on my battery, but the dealership claimed it was a bad electric switch and charged me close to $200 for that! They tried to charge me over $300, but I balked, and magically the price was reduced. I just do not trust these dealerships. Does anyone think repair shops actually sabatoge your car so you have to return with more work for them? I have noticed that a lot with many dealerships. I fix one thing, and another thing is wrong the next day! My car could go for a year or more with nothing wrong, and suddenly 2 things go wrong, one after another!
The dealership where I brought it charged close to $245 for the new battery and $50 each to reprogram my 2 FOBS-$345 in all! I asked a good friend who has a repair shop if that was too much, and he said that is pretty much the going rate. It only takes a few minutes to reprogram the FOBS, but you are paying for the expertise. I would have had my friend do it, but he claims he can not even get the battery because he is not a Vet shop. Then a day after I got the battery, my passenger side window would not come up. I brought it back assuming something was touched when they were working on my battery, but the dealership claimed it was a bad electric switch and charged me close to $200 for that! They tried to charge me over $300, but I balked, and magically the price was reduced. I just do not trust these dealerships. Does anyone think repair shops actually sabatoge your car so you have to return with more work for them? I have noticed that a lot with many dealerships. I fix one thing, and another thing is wrong the next day! My car could go for a year or more with nothing wrong, and suddenly 2 things go wrong, one after another!Last edited by prs62; Jul 26, 2008 at 04:44 PM.