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Discussion Starter #1
Any electrical guys out there?

Ok so here's my mystery problem. I seem to have an intermittent draw where whenever the car decides to I'll get up in the morning and my battery will be dead. Second new battery, new starter as well. Did a parasitic draw test at work today, at first it registered no draw then after about a half hour showed a 70 ma draw. So off I went pulling fuses and relays, pulled everything under the hood, no change so I moved onto the fuse box inside the car. Pulled everything there no change either, even completely unhooked the fuse box under the hood with no change. Asked one of the techs I worked with, he suggested disconnecting the alternator, no change. So now we're all stumped, when someone suggests disconnecting each plug on the PCM to isolate and cut my options in half. I unplug both wire spool, only to once again have no change in the draw. So then I say screw it I'll have to come back to it and plug everything all back together. Draw jumps up to 4.2 amps (as expected), then eventually falls to 1.5 amps. One of the techs comes over and unplugs the fuse box, it drops to 30 ma, plugs it back in and it stays at 30 ma for about a half an hour before dropping to 15 ma. And it stayed there for the next 3 hours or so until I unhooked the diag machine and left work.
 

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All the techs I've talked to have said 50 ma is generally the max you want to be at, although I don't have the actual vehicle specs.

If it is pretty close to spec, any suggestions on why my battery keeps dying?
 

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It's a 99 regal gs. The only aftermarket equipment I have is a jvc head unit and two 6x9s (not so professionally) installed by Mickey shorrs. The problem actually did start about a week after I had them install everything, I went back to them and they basically refused to do anything about it. But the battery tested bad so I replaced the battery, the problem persisted so I did a draw test and nothing registered. Fully charged the battery and it didn't die again until two weeks later (it's my daily driver). Heard a couple people say they had problems with interstate batteries testing good but actually being bad and not holding a charge so I had the battery warrantied out. This time it lasted about three weeks. I heard a theory from a tech at work that the starter was going bad and pulling too much so when I turn the key it would drain the battery and the lights would dim etc. but when I jumped it there was enough voltage from each cars to turn it over, said he had the same problem on his gp. So I replaced the starter over the weekend and it was dead again two days later. Oh and during the three weeks after warrantying the battery I thought I had it fixed so I also replaced the 4" speakers in the rear deck, when I did this I found wires shorting out to the body and just a real hack job so I cleaned up all the wiring while I was back there.

Sorry for the long posts just trying to give you as much of the complete story as I can.
 

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The only way you can find a power drain is to pull circuits and remove circuit breakers and fuses one at a time while monitoring the battery draw. When you hit the circuit with the problem, the draw will stop. You would be watching your DVOM while doing this of coarse.

Normally when I'm chasing a battery drain, I start at the fuse and relay box/boxes under the hood if equipted and at the insturment panel fuse box. If I hit a circuit here that shows a positive reaction, I look at a chassis schematic and follow this back one circuit at a time till isolated. This can be a lot of work(especially if your not accustomed to doing this type of diag). There are no "Silver Bullets" for a quick fix with many types of battery drains. Although one place I would look at first is the "battery saver" function. This is the circuit that shuts everything off when something is accidently left on(dome lights, etc). I had an Impala with an issue of this type. There doesn't necessarly have to be a short with this because if the Battery Saver does not work, various relays or breakers will stay hot and continue to draw off the battery.

Needless to say, wish you good luck.... Jake L.

PS, if you are not equipted for this search and find job, get on the phone and call all the independent shops in your area and find one that is accustomed to this type of repair. Point is, you do not want to pay for a tech to learn how to do this job. You want to pay for a tech who knows how to find the problem.
 

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Start with the main draws, if its a short circuit somewhere its going to be a needle in a haystack trying to find it. Fuel pump, radio, starter, lights, heater fan etc. If you know someone with a clamp on amp meter you can use that to help track it down. Honestly I would start at the radio.
 

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That's exactly what I did step by step and that why I'm so confused. Started under the hood pulling em one by one without pluging any back in so as not to give a false draw , when none of those dropped the draw I moved on to the fuse box in the car, that didn't drop it, so I disconnected the under the hood fuse box completely, disconnected the alternator,unplugged the oil pressure switch and sending unit. None of those dropped the draw so I talked to a tech who suggested pulling the pigtails of the PCM one at a time so I could at least cut the possible circuits in half and then use the process of elimination to further narrow it down by determining which circuits would be fused etc. I pulled both pigtails and neither of them dropped the draw, I consulted him and he has no clue. So basically I'm looking for a next step since Ive been working with cars long enough to know there's no such thing as a quick fix.

Btw as a temporary fix I got a battery safety switch so I can pop the hood and flip a switch to disconnect the battery, which I thought would be a nice added security feature in the ghetto lol
 

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That's exactly what I did step by step and that why I'm so confused. Started under the hood pulling em one by one without pluging any back in so as not to give a false draw , when none of those dropped the draw I moved on to the fuse box in the car, that didn't drop it, so I disconnected the under the hood fuse box completely, disconnected the alternator,unplugged the oil pressure switch and sending unit. None of those dropped the draw so I talked to a tech who suggested pulling the pigtails of the PCM one at a time so I could at least cut the possible circuits in half and then use the process of elimination to further narrow it down by determining which circuits would be fused etc. I pulled both pigtails and neither of them dropped the draw, I consulted him and he has no clue. So basically I'm looking for a next step since Ive been working with cars long enough to know there's no such thing as a quick fix.

Btw as a temporary fix I got a battery safety switch so I can pop the hood and flip a switch to disconnect the battery, which I thought would be a nice added security feature in the ghetto lol
Damn, you have chased that draw for a bit, I am not sure what I'd try next.
Here is what I got for my drain, I think mine is from my air shocks leaking, I'll know soon hopefully.

Amazon.com: Battery Tender 021-0128 Battery Tender Plus 12V Battery Charger: Automotive
 

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That thing looks pretty cool, I may have to pick one up myself. Let me know how it works for you.
Since getting the Battery Tender I've not had the battery go dead on me, it comes with a quick connect cable, and it is so small I leave it under my hood/on the upper radiator hose of my Park Ave, of course I let the engine cool a bit after trips before putting it back under there.
I almost bought a quick disconnect like you mentioned before I bought the maintainer, so far I'd say it was well worth what I paid for it, I was tired of constantly disconnecting my - battery cable, as I'd lose stored radio stations.
The only issue I've had is if I set my factory anti theft alarm
to on,occasionally it will go off, so without turning the alarm on I just manually lock my doors and it does not happen, of course it is pretty safe where I live, or I'd not feel comfortable leaving it off.

EDIT: I meant that when I get back from driving the car I'll leave the hood up for a few minutes, I'll let the battery maintainer sit on the air box for a bit, till the cat cools down a little, then since the quick connect is hooked directly to my + and the - of the battery, all I do is plug it in.
Once the car is cool I'll set that on the upper radiator hose, then if you make sure the wires are not near the hood latch, then you can easily shot the hood, so nobody can steal it..
It may be a little more work than with the disconnect you use, but at least you know every time you drive that you have a fully charged battery,
Mine had gotten so bad that every time I cut it off I had to use a jump box, as the battery would no longer hold a charge, I went through 5 batteries in 6 years, since getting this I have had no problems at all.
Of course I still need to do all the steps you have done to test for the draw, I think in my case it is my air shocks, I've heard that they did not make it to where the compressor could not come on when the car is off till 97', I am not sure how true that is though, I have never heard mine come on when the car is off, but it runs almost constantly when the car is on.

Some fairly common reasons I have heard of the draw is, power antennae, cigarette lighter socket, alternator rectifier bridge, light not cutting off,, like a hood or trunk light, or an improperly wired aftermarket stereo system.
 

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if the lead in the battery starts to pull up you'll get this same result. Brand new battery means nothing. Just something to think about. I've gone through 4 brand new crap Optimas
 

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Discussion Starter #17
Can I check this by popping the vents off the battery? May just be a coincidence, but optima and Interstate are now both owned by Johnson controls, who I have heard cut all quality controls and moved most plants to Mexico.
 

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Discussion Starter #18
My bad, double post. And williame if you know your air shocks are leaking I would just replace them either way, and then check and see if you still have a draw.
 

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I have run into batteries that had an internal short or something to make it go down. The way I found this was unhooked from the car/truck and fully charged. Let it set over the week end. Then compared the battery voltage measured directly at batt posts. In my case it went from 12.6 volts on a Friday to 11.9 on the next Monday...... Never seen air draw a battery down so a new one went in and away went the problem. Speaking of battery savers, make sure the one in the car is working. With todays cars and all the subsystems that draw power, these are pretty much a must and if not working, you will have a dead/low battery. I've seen a few tech posts on iATN where a bad ground circuit for the battery saver caused these to not function resulting in low batteries. Maybe take a look here also.
Jake L.
 

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I recently had trouble with cranking isues on my gp. I have an older Optima red top, and bought a Sears Die Hard Gold. Temporarily the cranking was okay. Recently, I realized that the starter was going out. I do not have an amperage draw meter that would handle the current. I replaced the starter yesterday. It worked great, and then it would just engage the solenoid. I check grounds and connections, and ended up jumping the car from the Optima....Aggravating that
the new Die Hard is bad. I suspected so when I brought it home and it took an initial heavy charge of 7-8 amps...cheers Kev
 
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