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[Guest]

I have a battery drain problem.
I've looked through your responses and haven't found a solution.
I have a 95 Chevy Blazer.
The problem SEEMED to start shortly after I gave a friend a jump.
The truck sat for a week and a half, and it was completely dead. 0
volts on the battery.
I've since replaced the battery (twice).
If I use the car for a long enough period, often enough, it doesn't
seem to have a problem, but if it sits for 2-3 days, it needs a jump to
get started.
I've pulled all the fuses, while testing the current draw with one wire
off the battery.
I've taken the alternator off, brought it to AutoZone and had it tested
(twice), it passed both times.
I disconnected the alternator and the current draw drops to 0, which
from what I've read means that the alternator probably has a bad diode.
But the alternator has passed the AutoZone test twice.
I'm not sure what to do, I've heard a lot of people have gotten charged
a lot of money to get a vehicles electrical problems tested and never
found a solution.
I'm trying to avoid buying a new alternator unless I'm quite certain
it's the problem. It's $100 I don't want to chance.
Any help you can give me would be greatly appreciated.

[80 Knight]

<epic1980@gmail.com> wrote in message
news:1131995535.192222.14040@z14g2000cwz.googlegroups.com...

[Guest]

Not everything is on your normal fuses. You said you checked shutoff
current drain
but you didnt tell us what it is.

Take off one of the battery cable terminals, measure the current draw while
the key
is off by inserting an ammeter in between battery post and its unconnected
cable.

You may have to wait until some of the electronic control modules go
dormant.
How much current do you read? It should be no more than about 150
milliamperes max.

******Let us know the reading, and we will go from there.******

Common problems include courtesy lights that are not shutting off. A 10 watt
courtesy
bulb would draw about 700-750 ma, and that will run your battery down pretty
quickly.

It is certainly not impossible that you did some damage to the system when
you gave
your friend a 'jump'. Done correctly, it usually goes fine, but if you
don't do it right,
you can damage diodes, etc.

[Jack]

On 14 Nov 2005 11:12:15 -0800, epic1980@gmail.com wrote:

In your description of the problem you said,

[Guest]

I have personally seen my Alternators, Batteries, and Starters pass
Autozone's tests and they were actually bad. I have actually had to
walk some of their personnel through the test because they didn't know
how to do it. (Not all stores apply to this). Try to find some local
auto shops that will do the testing for a minimal, or no charge. ex:
Pep Boys, Checkers, and Napa too. Have it tested at different places. I
went out and bought myself a cheap tester and it has been right
everytime.

[451CTDS]

I question the validity of a " Twilight Zone " test. Sure, they can
hook it up to a spinner, and see if it puts out juice. By your own
investigating, current draw drops to zero when alt. is unplugged means
the unit draws current. How about having a rebuilt / and your alt.
checked with a VOM for resistance from case to output terminal. A bad [
shorted ] diode will allow current flow from term to case.

[Reynaud]

"80 Knight" <80_knightREMOVEME@rogers.com> wrote in message
news:0ZWdnbYTF-cQZOXenZ2dnUVZ_sednZ2d@rogers.com...

[Guest]

Thank you all for your post, you've been a ton of help.
I've been busy and haven't gotten to check out any of your suggestions.
I think I'll try 451CTDS's suggestion and test the resistance.
If no luck, I'll bring it somewhere else and have the alternator
tested.
I just wish they'd let me return the alternator if that's not the
problem, but that's not the case.

H...@nospam.nix: I think it's drawing around 300 ma. But as much as
900, it changed on me (probably something to do with leveling out after
the battery was disconnected)
Thanks again, I'll post again when I have more info.

[Majestyk]

I have a similar "problem" with my Buick Park Avenue and I'm wondering if it's my alternator. Before getting a new battery, my car started up fine but the volt indicator went down quite a bit and then it started rapidly going between 12.1 volts to 12.9. I took the car to Canadian Tire and they said my battery was good. I then took it to a GM dealer and they said the battery had a bad cell and my alternator was good. I got a new battery and now the car starts at 13.9/14 and it goes down to 12.8 unless, I'm driving up hills than it dips back up to 13.1 to 13.3. The reading doesn't jump around quickly, or as low, like it did with the last battery. It will settle into the 12.8 range and stay there, except for hills. However, the other day, it did go down to 12.5 volts, which I've never seen it go that low with the new battery but it didn't stay there very long. I have no doubt the last battery had a bad cell since the new one does perform better but I'm wondering if there might be something wrong with the alternator as well, even though it checked out fine. It seems weird that my car starts around the 14 range and drops, considerably, as it starts warming up. With both batteries, particularly the old one, my car does have a weaker engine idle sound when left for a couple days. But it always starts up fine and in the normal volt range.

Jeff

[Guest]

<epic1980@gmail.com> wrote in message
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