Battery drains when the car sits for 3 days

oldsmobile
aurora

#1

My friends, my 1996 Olds Aurora is draining my battery when it sits idle (not started) for about 3 days. I will say I bought a reman battery because the Aurora has a monster battery to handle the V8 Northstar which means a $190 new battery. I realize a reman battery wont be great, but it should not be dying already. Am I more likely facing a vampire drain or an alternator issue? Thanks kindly


#2

Full check would be to disconnect the battery completely, reconnect in 3 days and see if it is dead. I doubt it will be. You likely have something draining energy. Binary search would be to take out 1/2 of the fuses and see if that helps, if not, test by taking the other half (to verify that you don’t have something with a line/fuse elsewhere like the starter solenoid, for instance, that is the culprit. (And keep when you find the issue is in 1/2 the fuses, cut that in half, etc. to chase it down to which fuse is the problem.)
Likely, with that kind of drain, if you went through the fuses one at a time, a fuse will spark when you take it out and reinsert it and that is the one. Something there is eating it up. Probably some wires where the insulation is missing and a partial short is drawing current. But once you have the fuse, you can verify, again, but leaving it out for 3 days to see if that was the issue. Also, you can then chase it down to the problem.


#3

Pulling the fuses and watching for one to spark when you put it back in, is a good idea. But you will have to wait until all the systems go into sleep mode. Many components stay on for awhile. Give it 30 minutes. If it was a more modern car, I would give it an hour at least.

When reinstalling the fuses, remember that you will have the door open and the fuse for the dome lights will spark as it should. There is also a live wire that keeps the radio clock and pre-sets.

You should check each bulb, under hood light, trunk light, and glove box light.

If the bulb is hot as soon as you get the hood, or trunk lid open, this means that the light has been on.

Sometimes you have to plan this out bny opening the trunk etc, and locate the bulb and access it. Then close the trunk and let the bulb cool for 5 minutes. Then open the trunk and touch the bulb ASAP.

Yosemite


#4

Hey Yosimite,
All my interior lights are out , the dome, door lights…glove box, all of them, and the fuse is not blown I physically checked, so any tests involving my interior lighting wont work, but thanks for getting involved. Auto Zone tested my battery and it failed at 84%, right after I drove it with ample time to let the alternator do its thing…so the beginning appears to be a $180 battery! (sometimes I hate the Northstar engine)…the battery is the size of a boat or truck battery…henceforth…pricey.
Where do I look when all the interior lights are out and the fuse isnt blown? Not a weak battery I assume.


#5

Please see my reply to Yosmete…it appears my battery failed the Auto Zone test, it only had 84%.
The fuse test run like that would be very complex, the Aurora is a very unique system, it has fuses and breakers in 4 locations! One regular by the drivers hood release, two sets under the back seat next to the battery (yes, it’s under the back seat!), one is behind the driver, the other behind the rear passenger, and one near the firewall under the hood. It appears I will have to start by replacing the battery, which blows since its nearly $200. I just replaced it a few months ago, but confession, I bought a reman.
I am certain you’re right about the parasitic draw, dollars to donuts all the interior lights being out isnt a coincidence (and the drivers power seat, and the trunk release, and the cruise control…I have yet to find one blown fuse. Suggestions what direction to take? Thanks for your time


#6

84% isn’t bad for a battery. Should be enough to run the car fine. Do you have a number in amps?

And if the lights and other things are out, there is a blown fuse somewhere, or several.

A bad battery can not hold a charge, and that may be causing the discharge in 3 days or so, or it could be a parasitic drain. Or a short in the wiring somewhere.


#7

You can get a meter for $5 and check every circuit. The meter is good for lots of other home and auto uses. When I had this problem I found a phantom circuit (a wire for a part my truck didn’t have, but others that used the same harness did) short.


#8

With that year/ model, under the hood, in that fuse box, you should also find a few fuses that are called “Maxi Fuses”. They range from 40 amp to 80 amp. They look like the common fuse, but 5 times bigger.

Did you check those.

Yosemite


#9

From what you say about the issue it does sound like you have a parasitic current draw on the battery. If you don’t have the proper tools to check that out then I suggest you have a shop check what the current draw is. They could also check the charging system and see how well that is working. Since you are getting a new battery you want to make sure that the charging system is working correctly with the new battery.

For your interior lighting issue I suggest you purchase a test light probe so you verify where power is getting to. At the fuse place the probe tip on each of the small metal slits on the top of and on each side of the fuse to verify power is getting through the fuse. If that is good then check the connections to the panel. The fuse for that circuit may be near the battery since power is applied at all times.


#10

How old is then battery, and where is it located? If the battery is under the hood and is more than four years old, that could be part of the problem. I have newer model GM cars with the battery in the trunk or under the rear seat, and those are original on a 2010, 2009, and even a 2005.


#11

Check the positive battery cable connection bolt to see if it looks like this.


Then check the terminal itself to see if it looks like this.

If so, replace the positive battery cable assembly.

Tester


#12

This may help. https://www.popularmechanics.com/cars/car-technology/a5859/how-to-stop-car-battery-drains/

The light does stay on?


#13

Check the battery connections for corrosion, battery load/conductance test, and measure the total phantom current drain is where to start imo. Let us know what you find. I expect that will provide a lot of clues what’s going on.


#14

Hey George,
I had it tested at 3 different shops, it failed all 3 so I replaced it. It was foolish of me to buy a reman battery, all they do is change out the acid…and I found one new for $129 (Firestone wanted $235!) so at least now you can walk me through some of my electrical issues with a “known-good” battery and chargimng system.
I’ll run the test off the negative terminal as suggested to measure mAh bleeding off, over 50 and I’ll know it’s a significant vampire draw… Thank you


#15

Thanks I did check them…I took it to 3 stores (Oreillys and 2 Auto Zone,s, battery failed all 3 tests so I replaced it. We can now begin to find the draw while ruling out the battery and alternator. I will test for a leak off the negative cable with my multimeter, and post the results. Thank you. Something is definitely strange, my AC shut off like a light switch and turned right back on, and it had “surges” where it blew harder and louder when I accelerated. Add no power to my drivers power seat, all my interior lights (I mean all , the dome, doors etc), the trunk release (but it works using my Fob), no cruise control power, no rear view mirrors power (external), yet I havent found one blown fuse…this will take all your skills! Appreciate your time


#16

It failed 3 seperate tests so I replaced it today, now to find the vampire draw and half a dozen systems not working (rear external power mirrors, cruise control, trunk release, drivers side power seat, all my interior lights and no blown fuses found…I will have to learn how to test the metallic relays…and I’ll run an OBDii scan, the KAM threw up a fault code last week. Let the fun begin!


#17

Good info, thanks…replaced the battery today and it appears my charging system is good. I tested the fuses (visual inspection) and none were blown where the int lamps were listed…I did buy a new test light and I’ll get to it
If no fuses are bad, I will likely check out all the metallic relays… the Aurora has a massive amount in 4 sections of the car


#18

Under the back seat, I will test all of them tonight, got a new lamp, thanks


#19

Bill Russell, I saw him in NY when I was a kid growing up in the Bronx (-;/
I replaced the battery after it failed tests at 3 shops, and I definitely have a vampire draw somewhere…to
kill the battery that fast…The Aurora uses a flippin’ marine sized battery series 79 840 CCA
So far, all the fuses I’ve checked (and visually inspected the ones that run the interior lights etc) none were blown
I’ll have to learn how to test relays (the big metallic “fuses/breakers”) as this car is the Caddy Northstar system.
It has 2 fuse banks under the back seat, the one by the driver/hood release and the one under the hood by the firewall I think. There is something very wrong, after i replaced the battery, while driving home in 105 temp, my AC shut off like a lightswitch, but only for a second and kicked back on. I’m hoping it’s just the “ECM” re-learning after being disconnected from power. I had a KAM error last week when I ran an OBDii test also


#20

Visually inspecting the fuses is good but until you verify that voltage is actually getting to both sides of the fuse using a suitable tester then you really don’t know what is happening. It is great you purchased a probe so now all you have to do is use it to check the sample points on top of both sides of the fuse to verify that voltage is present.

Relay operation is easy understand and check out using your new probe, they are just simply an electric switch which allows a small amount of control current to switch ON/OFF a large amount of current draw needed by high current draw items like blowers, headlights, and other similar electrical loads. Don’t confuse them with fuses or circuit breakers as they are a different animal. A resettable breaker may look similar to a relay but the operations of the two devices are not the same at all.