Draining Battery?
Thread Starter
Drifting
Joined: Oct 2005
Posts: 1,507
Likes: 7
From: Palmetto FL
St. Jude Donor '07
Draining Battery?
I'm trying to figure out what is draining my battery. The battery is one month old and I went to start it for the first time in 3 weeks and it wouldn't start. The battery wasn't completley dead (interior lights came on, fob worked, etc), but it would not turn over. Had to jump start it and it appears to be fully charged again (guage reads 13 - 14), and has started several times since. I pulled the codes, but no new codes.
If something is draining my battery, will a code be thrown? If not, can a technician determine what is draining the battery?
Thanks in advance for your help.
If something is draining my battery, will a code be thrown? If not, can a technician determine what is draining the battery?
Thanks in advance for your help.
Thread Starter
Drifting
Joined: Oct 2005
Posts: 1,507
Likes: 7
From: Palmetto FL
St. Jude Donor '07
When you say it appears fully charged (13-14), are you reading the voltage from the DIC ? YES
If so is that reading when the car is running? YES
Or is it with the car off and key turned to ACC? If running you are seeing the output voltage of the alternator not that of the battery.
When you put the new battery in did you drive the car for an hour or more on the new battery or just briefly and then leave it parked? I drove it around briefly after putting the battery in but during the next few days, I drove around quite a bit.
New batterys are NOT at full charge when you (or a shop) install them. They have enough of a charge to start the car and a bit more but need to be fully charged by either driving the vehicle for an hour or more with as few accessories on as possible or by using a trickle charger such as a battery tender.
I'd measure the voltage with a digital volt meter with the engine off. If the battery is truely fully charged expect to see something around 12.5 volts. (a reading of 12.1 won't cut it if you leave the car parked for weeks at a time.) If a digital volt meter does show a reading less than 12.5 would it be worth my while to hook the battery up to a trickle charger to fully charge the battery?
Read through this thread to see a bit more or do a search on battery.
http://forums.corvetteforum.com/show....php?t=1881551
Chuck S.
If so is that reading when the car is running? YES
Or is it with the car off and key turned to ACC? If running you are seeing the output voltage of the alternator not that of the battery.
When you put the new battery in did you drive the car for an hour or more on the new battery or just briefly and then leave it parked? I drove it around briefly after putting the battery in but during the next few days, I drove around quite a bit.
New batterys are NOT at full charge when you (or a shop) install them. They have enough of a charge to start the car and a bit more but need to be fully charged by either driving the vehicle for an hour or more with as few accessories on as possible or by using a trickle charger such as a battery tender.
I'd measure the voltage with a digital volt meter with the engine off. If the battery is truely fully charged expect to see something around 12.5 volts. (a reading of 12.1 won't cut it if you leave the car parked for weeks at a time.) If a digital volt meter does show a reading less than 12.5 would it be worth my while to hook the battery up to a trickle charger to fully charge the battery?
Read through this thread to see a bit more or do a search on battery.
http://forums.corvetteforum.com/show....php?t=1881551
Chuck S.
Tech Contributor
Joined: Dec 2003
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From: Horncastle Lincolnshire, England
2023 C5 of the Year Finalist - Unmodified
Or you could follow Bill Curlees guide and track it down yourself. Try this thread.
http://forums.corvetteforum.com/show...rent+draw+test
http://forums.corvetteforum.com/show...rent+draw+test
Thread Starter
Drifting
Joined: Oct 2005
Posts: 1,507
Likes: 7
From: Palmetto FL
St. Jude Donor '07
With some technical skills and the correct type of meter that can read up to 10 amps of current, you can certainly use Bill Curleys thread to track it down. I'd start with the simple stuff and charge it up fully and then see if it drains down again after several weeks of being parked. Your personal stuff says your from Ma. and Fl. If the car is currently located in Ma. where it is probably pretty cold, the battery may go down somewhat just from the cold. When I lived in Ct. I used to keep my car on the battery tender all winter, disconnecting it when the weather was nice enough to drive the car.
Chuck S.
Chuck S.
Again, thanks all for the quick responses. I appreciate it.
Tech Contributor
Joined: Dec 1999
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Thanks for the input. I'll trickle charge the battery until it is fully charged, then I'll use the correct meter to check the amps. I'll then use the Bill Curlee thread to locate the drain. The car is in Florida year round.
Again, thanks all for the quick responses. I appreciate it.
Again, thanks all for the quick responses. I appreciate it.
BC
Le Mans Master
Joined: Aug 2005
Posts: 5,375
Likes: 327
From: CA.
St. Jude Donor '13-'14-'15
Often a culprtit for draining the battery is the driver's side electric seat adjuster---Mine was bad--stayed on all the time--finally i just dis-connected the pigtails under the seat--fixed---
Thread Starter
Drifting
Joined: Oct 2005
Posts: 1,507
Likes: 7
From: Palmetto FL
St. Jude Donor '07
I don't hear any sounds coming from the drivers side area, but not sure if I should if the driver's side electric seat adjuster is bad.
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Thread Starter
Drifting
Joined: Oct 2005
Posts: 1,507
Likes: 7
From: Palmetto FL
St. Jude Donor '07
From the thread by Bill C.
Go to radio shack, sears, and even Auto Zone or Advanced. You do not need to get fancy or expensive. You need to measure AC Volts, DC Volts, Resistance (ohms) and Current. The meter should be able read to at least 10 AMPS. You should be able to find one for around $30-$50 bucks.
Ask the person at Radio Shack for help getting one with those specs. if that is where you go. I've had reasonable luck with knowledgeable folk at their stores (Ask for the manager, they should know their product line).
I also believe that the thread has pics and diagrams of how and where to connect the meter. Read the thread carefully if you are going to try this yourself expecially since you seem to have reservations about your technical/mechanical skills. Perhaps even printing it off so you have a guide in front of you if you tackle this yourself. You could take it to a shop but the cost of chasing electrical problems can get big in a hurry. It is usually time and materials and they won't tell you how long it is going to take because they don't know what they are getting into. Not sure what the hourly rate is in your area but in Tucson most places are in the $65 to $90 per hour range.
Hopefully the process of fully charging your battery will resolve the discharge problem you think you have and you won't have to go through this.
Has the battery come up to full charge yet?
Good Luck.
Chuck S.
Go to radio shack, sears, and even Auto Zone or Advanced. You do not need to get fancy or expensive. You need to measure AC Volts, DC Volts, Resistance (ohms) and Current. The meter should be able read to at least 10 AMPS. You should be able to find one for around $30-$50 bucks.
Ask the person at Radio Shack for help getting one with those specs. if that is where you go. I've had reasonable luck with knowledgeable folk at their stores (Ask for the manager, they should know their product line).
I also believe that the thread has pics and diagrams of how and where to connect the meter. Read the thread carefully if you are going to try this yourself expecially since you seem to have reservations about your technical/mechanical skills. Perhaps even printing it off so you have a guide in front of you if you tackle this yourself. You could take it to a shop but the cost of chasing electrical problems can get big in a hurry. It is usually time and materials and they won't tell you how long it is going to take because they don't know what they are getting into. Not sure what the hourly rate is in your area but in Tucson most places are in the $65 to $90 per hour range.
Hopefully the process of fully charging your battery will resolve the discharge problem you think you have and you won't have to go through this.
Has the battery come up to full charge yet?
Good Luck.
Chuck S.
Thread Starter
Drifting
Joined: Oct 2005
Posts: 1,507
Likes: 7
From: Palmetto FL
St. Jude Donor '07
Ended up bringing the car to the dealership. The drain was caused by a lumbar switch staying activated. Thanks to GMPP, cost me nothing but time.
Thanks to all who helped.
Thanks to all who helped.
Le Mans Master
Joined: Mar 2002
Posts: 8,466
Likes: 51
St. Jude Donor '17
I'm trying to figure out what is draining my battery. The battery is one month old and I went to start it for the first time in 3 weeks and it wouldn't start. The battery wasn't completley dead (interior lights came on, fob worked, etc), but it would not turn over. Had to jump start it and it appears to be fully charged again (guage reads 13 - 14), and has started several times since. I pulled the codes, but no new codes.
If something is draining my battery, will a code be thrown? If not, can a technician determine what is draining the battery?
Thanks in advance for your help.
If something is draining my battery, will a code be thrown? If not, can a technician determine what is draining the battery?
Thanks in advance for your help.
There is a large draw on the battery while sitting idle. Anything over 2 weeks of non driving you will see some issues. A battery tender should be used if you are not driving that often.
Their lumbar switch staying active is probably just what they said to charge GM. Let it sit again for 3 weeks and see what happens.
When i use my "lumbar switches" i can hear the motor running dont you?
Thread Starter
Drifting
Joined: Oct 2005
Posts: 1,507
Likes: 7
From: Palmetto FL
St. Jude Donor '07
the not driving it for 3weeks part is draining it.
There is a large draw on the battery while sitting idle. Anything over 2 weeks of non driving you will see some issues. A battery tender should be used if you are not driving that often.
Their lumbar switch staying active is probably just what they said to charge GM. Let it sit again for 3 weeks and see what happens.
When i use my "lumbar switches" i can hear the motor running dont you?
There is a large draw on the battery while sitting idle. Anything over 2 weeks of non driving you will see some issues. A battery tender should be used if you are not driving that often.
Their lumbar switch staying active is probably just what they said to charge GM. Let it sit again for 3 weeks and see what happens.
When i use my "lumbar switches" i can hear the motor running dont you?
Anyway, I'm going to let it sit as I usually do and see what happens.
Le Mans Master
Joined: Oct 2004
Posts: 9,369
Likes: 4
From: Zephyrhills, Florida
St. Jude Donor '06-'07-'08-'09-'10-'11-'12-'13
a no brainer to do .........simple.
Thread Starter
Drifting
Joined: Oct 2005
Posts: 1,507
Likes: 7
From: Palmetto FL
St. Jude Donor '07
I could do the same, but why should I have to? Not starting the car for a few weeks should not drain the battery to the point of the car not starting. Am I wrong in my thinking? If so, I have no problem hooking up a battery tender while I'm not driving it for a few weeks. I guess I'm being a bit stubborn since I never had to put a battery tender on it before.
Safety Car
Joined: Jan 2001
Posts: 4,978
Likes: 497
From: Hilton NY
The computers are on all the time and will drain a good battery in three weeks so that the car will not start. Lets say that you drive one day out of 20 and the car starts, the battery life will be shortened due to the constant computer drain the other 19 days. The rested battery drain is about 20 ma. You need to drive the car more, hook up a charger to the battery or disconnect the battery.
Le Mans Master
Joined: Mar 2002
Posts: 5,955
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From: PNW
I measured my parasitic current drain in "sleep mode" and it was 18~20 mA.
It takes about 15 or 20 minutes for the computers to go in to "sleep mode" for the current draw to fall down to this level.
Le Mans Master
Joined: Mar 2002
Posts: 5,955
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From: PNW
I calculated it once and it was more like 2 months at 20 mA draw for a good battery.
If a fully charged battery is not starting the car after sitting for 3 weeks then: a) the battery is defective and losing it's charge due self discharging or b) the parasitic draw is way over 20 mA in sleep mode.
Le Mans Master
Joined: Oct 2004
Posts: 9,369
Likes: 4
From: Zephyrhills, Florida
St. Jude Donor '06-'07-'08-'09-'10-'11-'12-'13
I could do the same, but why should I have to? Not starting the car for a few weeks should not drain the battery to the point of the car not starting. Am I wrong in my thinking? If so, I have no problem hooking up a battery tender while I'm not driving it for a few weeks. I guess I'm being a bit stubborn since I never had to put a battery tender on it before.
