[Z06] Battery Drain?? Need Your Help!!
Thread Starter
Melting Slicks
Joined: Nov 2005
Posts: 2,361
Likes: 3
From: Charlotte Area NC
Battery Drain?? Need Your Help!!
Well, the 2003 Z06 had the following symptoms and then result...
Over the last few days:
1. Windows rolling up slowly
2. Clock not keeping time
3. Code tripped for "service active handling" and "traction control"
4. When applying brakes, headlights would dim
5. Sometimes a hard start
At this point, I hooked up the volt meter. With the engine off and the A/C on, headlights on, radio on, etc (means by which to drain battery) the battery still showed 12.xx volts. Then I started the engine with all of these things going and it moved up to 14.xx volts.
This Morning:
1. No power what so ever. No lights in car, engine not turning over.
?????SO, what is going on????? The battery seems fine, but even when the car is off, there is a drain somewhere. Any idea where this mysterious drain is coming from? PLEASE HELP!!!
THANKS!
Over the last few days:
1. Windows rolling up slowly
2. Clock not keeping time
3. Code tripped for "service active handling" and "traction control"
4. When applying brakes, headlights would dim
5. Sometimes a hard start
At this point, I hooked up the volt meter. With the engine off and the A/C on, headlights on, radio on, etc (means by which to drain battery) the battery still showed 12.xx volts. Then I started the engine with all of these things going and it moved up to 14.xx volts.
This Morning:
1. No power what so ever. No lights in car, engine not turning over.
?????SO, what is going on????? The battery seems fine, but even when the car is off, there is a drain somewhere. Any idea where this mysterious drain is coming from? PLEASE HELP!!!
THANKS!
Team Owner
Joined: Mar 2007
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From: Right Corner Pocket of Illinois
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St. Jude Donor '12 thru '26
Mine (02) did the same things! Battery showed 12 V+ but went down to 2 V when tested with a "battery load tester". After a jump start the car was running on alternator power only, couldn't even raise the headlights. Replaced the 5 year old OE battery with a new one and all has been fine since. DON'T over tighten the terminals!
Race Director
Joined: Jun 2005
Posts: 17,640
Likes: 1
From: Lenoir City TN
St. Jude Donor '08-'09-'10-'11
Mine (02) did the same things! Battery showed 12 V+ but went down to 2 V when tested with a "battery load tester". After a jump start the car was running on alternator power only, couldn't even raise the headlights. Replaced the 5 year old OE battery with a new one and all has been fine since. DON'T over tighten the terminals!
Typical when a battery drops a cell.
Instructor
Joined: Dec 2006
Posts: 133
Likes: 0
From: Inver grove heights, MN
someone can correct me if I am wrong. But, I believe if you want to tell if something is drawing power. You will have to put your volt ohmeter on the amps scale.Then put it in series with your positive post and positive battery lead. It will show how many amps is currently being drawn with the car off. It sounds to me like your battery is just toast. From everything I have read the A/C delco will die prematurely. If you don't want to change it, for preventitive maintenance, then take it to O'reillys,Autozone, or Napa whatever your preference and have them load test the battery, when its charged up. They will be able to do it in the car if you don't want to take it out.
Thread Starter
Melting Slicks
Joined: Nov 2005
Posts: 2,361
Likes: 3
From: Charlotte Area NC
the funny thing
Car has only 19xxx miles and the battery has already been replaced with a NAPA battery.
I dropped the car off at the dealer this morning and after running some initial tests, they stated that there is a "draw" or a "short" coming from somewhere that is draining the battery.
Car only has Halltech intake, Borla Stingers, C6 Z06 shifter...previous owner had wired the car for a radar detector as well.
I'm thinking the short is coming from the air intake electrical connection, where the c6 Z06 shifter was installed, or the wiring for the radar detector.
Any other thoughts???
I dropped the car off at the dealer this morning and after running some initial tests, they stated that there is a "draw" or a "short" coming from somewhere that is draining the battery.
Car only has Halltech intake, Borla Stingers, C6 Z06 shifter...previous owner had wired the car for a radar detector as well.
I'm thinking the short is coming from the air intake electrical connection, where the c6 Z06 shifter was installed, or the wiring for the radar detector.
Any other thoughts???
Thread Starter
Melting Slicks
Joined: Nov 2005
Posts: 2,361
Likes: 3
From: Charlotte Area NC
I hope the dealer can find the problem. Someone mentioned that the glove box light could be an issue. Is this true??
Could the short be caused by a blown fuse somewhere? Seems that so many vette owners struggle with the "electrical demons"
Could the short be caused by a blown fuse somewhere? Seems that so many vette owners struggle with the "electrical demons"
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Drifting
Joined: May 2000
Posts: 1,797
Likes: 0
From: Thompson Falls MT
Here's a thread on how to determine if you have a parasitic drain on your battery.
http://forums.corvetteforum.com/show...hlight=battery
http://forums.corvetteforum.com/show...hlight=battery
3rd Gear
Joined: May 2006
Posts: 3
Likes: 0
Try to determine the health of the battery first. The battery's voltage without a load should be 12.6 volts. Not sure what test equipment is used today but in my day we would use a Sun VAT-40. The battery should be above 10volts when a load equal to half of its CCA is applied. If it fails that test then a charge test should be conducted to see if the battery will accept and hold a charge. A automatic 30amp to trickle charger should be applied overnight and then the battery load retested.
Assuming the battery passes then I would then check the charging system. At idle the electrical system should be at 14.7 volts (or near it). We should be able to load the charging system up to or close to the alternator's capacity (amp rating and still maintain 14.7 volts or so. (with the egine rpm at 2k).
Assuming the charging system passes I would then check the current draw of the starter motor (Again, using test equipment like the VAT-40)
Assuming the starting circut passes I would then check for excessive current draw by first disconnecting the output of the alternator (factor out faulty diodes) and then factor out secondary circuts (by pulling fuses).
Good luck!
Craig
Assuming the battery passes then I would then check the charging system. At idle the electrical system should be at 14.7 volts (or near it). We should be able to load the charging system up to or close to the alternator's capacity (amp rating and still maintain 14.7 volts or so. (with the egine rpm at 2k).
Assuming the charging system passes I would then check the current draw of the starter motor (Again, using test equipment like the VAT-40)
Assuming the starting circut passes I would then check for excessive current draw by first disconnecting the output of the alternator (factor out faulty diodes) and then factor out secondary circuts (by pulling fuses).
Good luck!
Craig
