Battery boggle
Thread Starter
Drifting
Joined: Feb 1999
Posts: 1,481
Likes: 1
From: San Diego CA
Battery boggle
Okay, I'm a bit stumped. I've been having problems with my '99 Coupe. If I let it sit for as short as a week, the battery is pretty much dead.
The battery is an Optima Yellow Top. I ran some tests... parked and "resting", the car draws 7ma. Not much at all. After getting this number, I disconnected the battery from the car, charged it and started taking voltage readings. It started at 12.7v and after two days it's still fully charged at 12.68v.
I'm at a loss. The current draw does not seem to be nearly enough to drain the battery in a week, but the battery seems fine.
I'm even more suspicious because I have a Jeep Cherokee with the same battery (bought at the same time) and it dies in a week too. I haven't gathered numbers on the Jeep yet but this is really weird.
Any thoughts?
Thanks!
Mike
The battery is an Optima Yellow Top. I ran some tests... parked and "resting", the car draws 7ma. Not much at all. After getting this number, I disconnected the battery from the car, charged it and started taking voltage readings. It started at 12.7v and after two days it's still fully charged at 12.68v.
I'm at a loss. The current draw does not seem to be nearly enough to drain the battery in a week, but the battery seems fine.
I'm even more suspicious because I have a Jeep Cherokee with the same battery (bought at the same time) and it dies in a week too. I haven't gathered numbers on the Jeep yet but this is really weird.
Any thoughts?
Thanks!
Mike
Drifting
Joined: Jul 2004
Posts: 1,571
Likes: 1
From: Hollywood Md
Mike, 7ma is not enuf to draw down a battery in a week. In fact, 7ma is much lower than I've experienced. About 20-40 ma is the norm. If you're sure the battery is good, and you're sure you read the meter correctly (right scale etc.) I'm at a loss as to your problem. What was the battery voltage when dead?
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
There have been a number of people with a simular issue. Are you sure that your reporting the correct milliamp reading When i read mine with my FLUKE digital it read ..020 amps (20 milliamps) That is just what a 02 C5 should read.
I answered a PM to another forum member that might also help you. Take a look at it and see what you think
Here is the entire PM:
Originally Posted by 98droptop
Bill,
I Have been suffering with some sort of drain for awhile on the Optima. Trickle charged the battery last night and had a couple of auto parts stores check it today. The verdict is that the battery is good. I hook the meter up as outlines in the pictures and I have the same 0.020 on the display that you show on yours. So it appears that the draw isn’t abnormal. The only other thing I can think of is that the Alternator isn’t providing enough charge. Any additional thoughts?
Ron
Ron
I dropped you a post yesterday but my computer shut down as I was sending it and I'm not sure that you got it. Anyway,,I will try again:
The 97,98 and 99 C5's have active/passive switches on the FOB's and sense when the FOB is with in range of the car. When you BCM is a sleep, if the FOB is in the active mode and the DIC settings allow the car to wake up "FOB setting ACTIVE", every time the car senses the FOB, it will wake up and turn on what ever you have programmed into the DIC. If you set yours up like me, I have everything turned on!
There have been quite a few people who have had battery issues and found out that where they store the FOB allows the car to wake up enough to effect battery life.
Recommend that you go into the DIC functions and turn the FOB stuff OFF!!! Also turn the FOB slider switch so that it does not automatically unlock the doors!
Hope that works for you.
Let me know how you make out.
BC
__________________
bill327
Bill Curlee
I answered a PM to another forum member that might also help you. Take a look at it and see what you think
Here is the entire PM:
Originally Posted by 98droptop
Bill,
I Have been suffering with some sort of drain for awhile on the Optima. Trickle charged the battery last night and had a couple of auto parts stores check it today. The verdict is that the battery is good. I hook the meter up as outlines in the pictures and I have the same 0.020 on the display that you show on yours. So it appears that the draw isn’t abnormal. The only other thing I can think of is that the Alternator isn’t providing enough charge. Any additional thoughts?
Ron
Ron
I dropped you a post yesterday but my computer shut down as I was sending it and I'm not sure that you got it. Anyway,,I will try again:
The 97,98 and 99 C5's have active/passive switches on the FOB's and sense when the FOB is with in range of the car. When you BCM is a sleep, if the FOB is in the active mode and the DIC settings allow the car to wake up "FOB setting ACTIVE", every time the car senses the FOB, it will wake up and turn on what ever you have programmed into the DIC. If you set yours up like me, I have everything turned on!
There have been quite a few people who have had battery issues and found out that where they store the FOB allows the car to wake up enough to effect battery life.
Recommend that you go into the DIC functions and turn the FOB stuff OFF!!! Also turn the FOB slider switch so that it does not automatically unlock the doors!
Hope that works for you.
Let me know how you make out.
BC
__________________
bill327
Bill Curlee
Thread Starter
Drifting
Joined: Feb 1999
Posts: 1,481
Likes: 1
From: San Diego CA
Doh! Sorry to cause hate and discontent but that was a typo. The current draw is 70ma, not 7ma. Still, as I (tried) to say, it's not much.
The fobs are not in auto mode.
Since the battery seems happy on it's own, I guess I'll hook it back up through the meter and monitor the current for a few days along with the voltage change and I'll post what I find.
Thanks!
Mike
The fobs are not in auto mode.
Since the battery seems happy on it's own, I guess I'll hook it back up through the meter and monitor the current for a few days along with the voltage change and I'll post what I find.
Thanks!
Mike
Thread Starter
Drifting
Joined: Feb 1999
Posts: 1,481
Likes: 1
From: San Diego CA
Okay, just hooked the car back up. Big change from my last test. Now the car is drawing about 450ma when resting. That's a ton! I looked in my DIC options menu and there is no way to disable the auto unlock setting. My FOB switch is off but other than that, I don't know where to look.
I've been thinking about what electrical accessories I have on the car...
iPod2Car Adapter: Unpluged and saved 10ma or so.
LapTrax TracActive: Uses switched ignition power.
V1 Radar Detector: Uses switched ignition power.
Vinci Fan Controller: Uses switched ignition power.
Window Commander: Unknown. This piggybacks on the windows controllers and rolls down the windows when you press unlock twice. From what I understand, this should draw no power when not in use.
I can't think of anything else. Obviously, almost half an amp at rest is way out of the norm.
Does anyone have any ideas where to start chasing this down?
Thanks!
Mike
I've been thinking about what electrical accessories I have on the car...
iPod2Car Adapter: Unpluged and saved 10ma or so.
LapTrax TracActive: Uses switched ignition power.
V1 Radar Detector: Uses switched ignition power.
Vinci Fan Controller: Uses switched ignition power.
Window Commander: Unknown. This piggybacks on the windows controllers and rolls down the windows when you press unlock twice. From what I understand, this should draw no power when not in use.
I can't think of anything else. Obviously, almost half an amp at rest is way out of the norm.
Does anyone have any ideas where to start chasing this down?
Thanks!
Mike
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Thread Starter
Drifting
Joined: Feb 1999
Posts: 1,481
Likes: 1
From: San Diego CA
Okay, this is really annoying. I charged everything up so I could play with fuses today. Last night I removed my Vinci fan controller. I don't suspect it had anything to do with it (I need my car to warmup faster now that I drive it a short distance to work) but it should be mentioned.
So, now the car is back to 80ma or so. Last week it was at 200ma or more. Whatever is going on seems to be very inconsistant. I'm not sure how to chase it down.
I just hooked up the iPod adapter again (but without the iPod connected) and played with the door locks, hatch and Window Commander functions. Now it's resting at about 100ma.
I take it that 100ma is still more than I should see?
Any suggestions?
Mike
So, now the car is back to 80ma or so. Last week it was at 200ma or more. Whatever is going on seems to be very inconsistant. I'm not sure how to chase it down.
I just hooked up the iPod adapter again (but without the iPod connected) and played with the door locks, hatch and Window Commander functions. Now it's resting at about 100ma.
I take it that 100ma is still more than I should see?
Any suggestions?
Mike
Last edited by Mike Schriber; Nov 11, 2006 at 05:39 PM.
Pro
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I do not see you mention if you used a battery load tester to see if there is a bad cell for the voltage would show fine but would not handle current draw.
When doors are 1st closed current draw can be about 800 mAmps for about 10 minutes and then drop.
There could be a weak relay in any function of car that gets stuck and GM suggests everything be moved to cause relay to change states
Check relay for the light under the hood and also if your using some bypass for column lock.
When doors are 1st closed current draw can be about 800 mAmps for about 10 minutes and then drop.
There could be a weak relay in any function of car that gets stuck and GM suggests everything be moved to cause relay to change states
Check relay for the light under the hood and also if your using some bypass for column lock.
Thread Starter
Drifting
Joined: Feb 1999
Posts: 1,481
Likes: 1
From: San Diego CA
Hey, good point. I do have a column lock bypass installed. Are these known for battery drain? I thought the circuit was only live when the column was being locked and unlocked.
I have not done a load test, but with the draw being so high it seems to be a pretty clear cause and effect type situation.
I just finished some more tests. The car seems to be pretty consistant at 80-100ma once it settles down. If I pull the fuse for the driver's seat system, the draw drops to 56ma. If I reset and then pull the radio fuse, the draw drops to 76ma. If I pull both, I get down to 24-25ma.
So, the seat computer (which operates properly) seems to draw 20ma. The radio on it's own draws about 10ma but seems to draw more like 20ma when the seat fuse is pulled.
Any ideas?
Mike
I have not done a load test, but with the draw being so high it seems to be a pretty clear cause and effect type situation.
I just finished some more tests. The car seems to be pretty consistant at 80-100ma once it settles down. If I pull the fuse for the driver's seat system, the draw drops to 56ma. If I reset and then pull the radio fuse, the draw drops to 76ma. If I pull both, I get down to 24-25ma.
So, the seat computer (which operates properly) seems to draw 20ma. The radio on it's own draws about 10ma but seems to draw more like 20ma when the seat fuse is pulled.
Any ideas?
Mike
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Originally Posted by Mike Schriber
Hey, good point. I do have a column lock bypass installed. Are these known for battery drain? I thought the circuit was only live when the column was being locked and unlocked.
I have not done a load test, but with the draw being so high it seems to be a pretty clear cause and effect type situation.
I just finished some more tests. The car seems to be pretty consistant at 80-100ma once it settles down. If I pull the fuse for the driver's seat system, the draw drops to 56ma. If I reset and then pull the radio fuse, the draw drops to 76ma. If I pull both, I get down to 24-25ma.
So, the seat computer (which operates properly) seems to draw 20ma. The radio on it's own draws about 10ma but seems to draw more like 20ma when the seat fuse is pulled.
Any ideas?
Mike
I have not done a load test, but with the draw being so high it seems to be a pretty clear cause and effect type situation.
I just finished some more tests. The car seems to be pretty consistant at 80-100ma once it settles down. If I pull the fuse for the driver's seat system, the draw drops to 56ma. If I reset and then pull the radio fuse, the draw drops to 76ma. If I pull both, I get down to 24-25ma.
So, the seat computer (which operates properly) seems to draw 20ma. The radio on it's own draws about 10ma but seems to draw more like 20ma when the seat fuse is pulled.
Any ideas?
Mike
There is more than one fuse for the power seat system. See if you can remove each fuse and use the amp meter in the seat fuse slot to See if it is drawing current. Compare it to the passengers side (If you have passengers side power seats)
Here are all of the fuses.
Left seat:
SCM-L mini fuse#4
PWR ST/DVR circuit breaker# 35
LUMBAR mini fuse#4
Right Seat:
SCM-L mini fuse#3
PWR ST/DVR circuit breaker# 36
LUMBAR mini fuse#3
If the switch are not working properly, the seat will attempt to drive all of the time and keep tripping the breakers (which reset by them selves)
There are also Three fuses and one relay for the radio:
RDO/CD mini fuse# 5
DRO/ANT mini fuse# 24
BOSE mini fuse# 28 For the sub woofer amps. They are controlled by "BOSE" mini relay # 43
Hope this helps.
Bill
Thread Starter
Drifting
Joined: Feb 1999
Posts: 1,481
Likes: 1
From: San Diego CA
Hey Bill, thanks for the info.
Where the heck are the circuit breakers? I see them on the list but I have no idea where they are on the car.
The car seems to be brain dead. I pulled the Bose fuse and gained a few mimiamps. The same for the lumbar. Now I put everything back it and after opening and closing the door and letting it settle, it's now sitting at 60ma.
What the heck?
Mike
Where the heck are the circuit breakers? I see them on the list but I have no idea where they are on the car.
The car seems to be brain dead. I pulled the Bose fuse and gained a few mimiamps. The same for the lumbar. Now I put everything back it and after opening and closing the door and letting it settle, it's now sitting at 60ma.
What the heck?
Mike
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
The breakers are in the instrument panel fuse center. They are metal cans and if you look at the lay out instructions inside the cover, you will see where they are. If I were you I would start pulling fuses and relays one at a time and see if you can find the draws.
Another area that can cause mysterious current draws is the alternator. If it has a bad diode inside the alternator it will draw current when the engine is off. Take off the RED WIRE on the back and see how much current it is pulling. Just insert the amp meter between the wire and the terminal.
BC
Another area that can cause mysterious current draws is the alternator. If it has a bad diode inside the alternator it will draw current when the engine is off. Take off the RED WIRE on the back and see how much current it is pulling. Just insert the amp meter between the wire and the terminal.
BC
Thread Starter
Drifting
Joined: Feb 1999
Posts: 1,481
Likes: 1
From: San Diego CA
Okay, I just disconnected the battery, let it sit and then reconnected it.
Now the car is sitting at about 66ma. I pulled the lumbar with no difference. Pulling the driver's seat power fuse drops it to 55ma.
I'm at a loss. I can't think of a reson that pulling fuses and putting them back in should make a difference.
I'm going to pull the meter out of the loop, start the car, then put the meter back in the loop and check the readings.
What should the car be drawing at rest anyway?
Thanks!
Mike
Now the car is sitting at about 66ma. I pulled the lumbar with no difference. Pulling the driver's seat power fuse drops it to 55ma.
I'm at a loss. I can't think of a reson that pulling fuses and putting them back in should make a difference.
I'm going to pull the meter out of the loop, start the car, then put the meter back in the loop and check the readings.
What should the car be drawing at rest anyway?
Thanks!
Mike
