Battery drain
Thread Starter
Burning Brakes
Joined: May 2000
Posts: 1,160
Likes: 10
From: Nashville TN
Battery drain
Alright, I have a '93 Coupe to start. It has an aftermarket iginition(Crane Cames) & coil, a disc changer, and 2 lit gauges. My batttery slowly drains, I mean real slowly. It usually works fine for about a week or a little less and then the problems start happening, SYS light, hard to start, etc. I tested the draw and it is way below the max of 50mA. So, my first thought was Alternator. I took it to Autozone, the alternator out of the car, but they said it was good(Though I greatly question their competence). Any ideas here guys? Is what I have too much for the stock alternator, it doesn't seem so, but I'm not really the electrical guru. I have no squeal to indicate a slipping belt. I have replaced the starter a couple of years ago with some piece of junk that they put in there at the shop, but I don't believe that would have anything to do with this problem. Every time I replace the battery(I love warranties) it fixes itself for another week or so. Idle is average.
Not sure if this is relevant, but my PKE transmitter got a dead battery and I never replaced it so I just leave it in my room and use the keys to do the work. I don't HAVE to have this do I?
[Modified by kman0066, 12:38 AM 2/26/2004]
Not sure if this is relevant, but my PKE transmitter got a dead battery and I never replaced it so I just leave it in my room and use the keys to do the work. I don't HAVE to have this do I?
[Modified by kman0066, 12:38 AM 2/26/2004]
Safety Car
Joined: May 2003
Posts: 4,283
Likes: 0
From: Houston Texas
Re: Battery drain (kman0066)
Battery drains can be a female dog to find. Your going to have to systematically check everything one at a time and see what makes a difference. Mine was the little door switch for the interior light that was on passenger side. It eventually killed my battery until I realized that little simple thing was it.
Thread Starter
Burning Brakes
Joined: May 2000
Posts: 1,160
Likes: 10
From: Nashville TN
Re: Battery drain (BAM92)
Yeah, I already know I'm in for an experience :U
Really though, I just want to make sure my alternator is up to the job. I think I've heard the newer Vette's (95-96) have bigger alternators. I want to see if I will need to upgrade or not.
Really though, I just want to make sure my alternator is up to the job. I think I've heard the newer Vette's (95-96) have bigger alternators. I want to see if I will need to upgrade or not.
Team Owner
Joined: Mar 2001
Posts: 54,124
Likes: 30
From: Cincinnati, Oh USA
Re: Battery drain (kman0066)
If you are well below 50 ma. and your battery discharges after 1 week of sitting, I would check the state of charge. Measure the battery voltage at the battery terminals with an accurate voltmeter. 12.0 volts is discharged , 12.9v
or higher is considered fully charged. Where is yours? if it is close to 12.0 volts, then it is discharged and sitting only makes it more discharged. If it is fully charged, measure the voltage after 24 hours and see what the state of charge is. If it dramatically loses voltage in 24 hours and the leakage current is below 50 ma., then you have a battery at the end of its life. I recommend you charge your battery up with a battery charger for at least 24 hours (10 amp charger) and measure the battery voltage 2 or more hours after the charger is turned off and see what the state of charge is. It should be close to 12.9 volts and if not, the battery cannot accept a full charge and is at the end of its life, no matter when you bought it.
or higher is considered fully charged. Where is yours? if it is close to 12.0 volts, then it is discharged and sitting only makes it more discharged. If it is fully charged, measure the voltage after 24 hours and see what the state of charge is. If it dramatically loses voltage in 24 hours and the leakage current is below 50 ma., then you have a battery at the end of its life. I recommend you charge your battery up with a battery charger for at least 24 hours (10 amp charger) and measure the battery voltage 2 or more hours after the charger is turned off and see what the state of charge is. It should be close to 12.9 volts and if not, the battery cannot accept a full charge and is at the end of its life, no matter when you bought it.
Thread Starter
Burning Brakes
Joined: May 2000
Posts: 1,160
Likes: 10
From: Nashville TN
Re: Battery drain (jfb)
Yeah, this isn't the first battery. I replaced quite a few and I doubt I am just that unlucky to get that many bad batteries. Something in the car is killing them. It never sits for more than a few days to.
Hey guys, is there a way I can test if the car is charging while it is running. It doesn't appear that my problem is happening while the car is off, so is there a point to measure for a charge. Other than the volts of course, it does read 14
[Modified by kman0066, 9:34 PM 2/26/2004]
Hey guys, is there a way I can test if the car is charging while it is running. It doesn't appear that my problem is happening while the car is off, so is there a point to measure for a charge. Other than the volts of course, it does read 14
[Modified by kman0066, 9:34 PM 2/26/2004]
Race Director
Joined: Feb 2004
Posts: 12,517
Likes: 19
Re: Battery drain (kman0066)
The lights would go out and the timer would still pull current somehow. Pull dome lite fuse and see if this changes anything. By the way , I thought 15-18 ma. was a more current draw? I am not positive about this but this is my recallection
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Team Owner
Joined: Mar 2001
Posts: 54,124
Likes: 30
From: Cincinnati, Oh USA
Re: Battery drain (kman0066)
If your voltmeter reads 14 v when the engine is running then your alternator is working properly. Each time your battery runs down it loses some of its amp-hour capacity. Car batteries are not designed for deep discharge and using them this way shortens their life. When your battery runs down you should charge it all the way back up. I would check in the dark, your underhood lights, vanity mirror lights, console compartment light. Do you have a radar detector? You might try disconnecting your non stock electrical gadgets and see how long your battery lasts. You must have more than 50 milliamps of leakage. Driving your car for 15 minutes after you get it started will not charge the battery up! Use a battery charger!
Thread Starter
Burning Brakes
Joined: May 2000
Posts: 1,160
Likes: 10
From: Nashville TN
Re: Battery drain (jfb)
You must have more than 50mA of leakage? Ok, this is a good development. Mine is showing 6mA with the underhood lights disconnected of course. With them connected, it goes to 3.7 A.
My voltmeter my be going kaput though, I just tested the battery and it said that it had 22 volts.
Just a note, this happens from a fresh battery, brand new, fully charged, driven often. This is not from it just sitting around or not getting recharged properly. The battery is just slowly draining, driven or not driven and I am getting 6 mA of draw with the car off and the underhood lights disconnected. I have replaced the battery, many times, it does it just the same. I get the Service ASR light first, then the SYS light, then hard to start, and then dead. I have tried a 24 hour charge when the first symptoms start appearing, all this does is give me a couple of days and the symptoms come back.
Can someone explain to me, because I thought the more Amps the more current is being drawn. So, 6mA would be less draw as opposed to 50mA.
[Modified by kman0066, 11:25 PM 2/26/2004]
My voltmeter my be going kaput though, I just tested the battery and it said that it had 22 volts.
Just a note, this happens from a fresh battery, brand new, fully charged, driven often. This is not from it just sitting around or not getting recharged properly. The battery is just slowly draining, driven or not driven and I am getting 6 mA of draw with the car off and the underhood lights disconnected. I have replaced the battery, many times, it does it just the same. I get the Service ASR light first, then the SYS light, then hard to start, and then dead. I have tried a 24 hour charge when the first symptoms start appearing, all this does is give me a couple of days and the symptoms come back.
Can someone explain to me, because I thought the more Amps the more current is being drawn. So, 6mA would be less draw as opposed to 50mA.
[Modified by kman0066, 11:25 PM 2/26/2004]
Thread Starter
Burning Brakes
Joined: May 2000
Posts: 1,160
Likes: 10
From: Nashville TN
Re: Battery drain (kman0066)
Alright, I just thought of something relevant. I replaced the battery a few years ago and stripped out the battery hold down bolt. In my genius, I have not worried about it and left the battery as is. Could it be possible that the new found freedom for the battery is causing it to keep cr*pping out.
I guess I'll try bracing the battery better. I'll give this battery a fresh charge and see what happens. I also need to go buy a new voltmeter so I don't get that 22 volt reading from the battery.
I guess I'll try bracing the battery better. I'll give this battery a fresh charge and see what happens. I also need to go buy a new voltmeter so I don't get that 22 volt reading from the battery.
Team Owner
Joined: Mar 2001
Posts: 54,124
Likes: 30
From: Cincinnati, Oh USA
Re: Battery drain (kman0066)
I doubt the hold down bolt is involved, but replace it anyway! With your admission of a wrong voltage reading, I don't trust your leakage current reading either! Go buy a new VOM and disconnect the neg cable and measure the leakage current after the courtesy lights time out. If in excess of 50 ma. (I'll bet you 5 White Castles and a Coke it is) start pulling fuses one at a time and watch the ammeter. The circuit with the battery draining current will be indicated by the dramatic drop in leakage for a particular fuse pulled. You will have to pull the courtesy light fuse since you have to have the right door open to get to the fuse panel.
Racer
Joined: Sep 1999
Posts: 319
Likes: 0
From: Fishkill New York
Re: Battery drain (kman0066)
I learned a hard lesson a few years ago with a dead battery. Somehow the vanity light on the passenger side was switched on and due to the visor always being up I never noticed. It took 2 dead batteries to figure it out.
Instructor
Joined: Oct 2002
Posts: 165
Likes: 0
Re: Battery drain (kman0066)
i too am experiencing drain on my 84...battery goes dead after about 12-24hrs...i'm gonna try some of the tips listed above as i'm pretty sick of jumping the thing everytime i wanna drive it....
anyone have any other suggestions they wanna throw out? not trying to hijack this but we're experiencing similar problems and i figured with everyone already posting here a seperate thread would be about worthless...
anyone have any other suggestions they wanna throw out? not trying to hijack this but we're experiencing similar problems and i figured with everyone already posting here a seperate thread would be about worthless...
