Charging issues

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bkbimmer
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Charging issues

Post by bkbimmer »

I have been having an anoying charging issue that I have yet to figure out.

When the car is running the alt. light on the dash stays on very dim, the more things I turn on it gets a tiny bit brighter each time, the alt. is charging and I have swapped then out and still does the same thing, I have checked all of my grounds and they all seem to be good!

This issue came out of no where after we had a long stretch of really cold weather, I even put in a new optima battery thinking that could be it, but no!

Any insight would be greatly appreciated!

Thanks

Brent
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Charging issues

Post by grumpsjr »

I fought this one a few years back - in my case it was the voltage regulator in the alt. but since you have changed the alternator, that should not be an issue.  The other problem I had were - you guessed it - grounds.  The light simply measures voltage drop between alternator and battery.  If you have parasitic losses from grounds, this can cause the light to illuminate dimly.  Time to clean grounds.

Hope this helps...
Brian

On Tue, Feb 2, 2010 at 10:49 PM, bkbimmer <bk_burnout@hotmail.com (bk_burnout@hotmail.com)> wrote:
I have been having an anoying charging issue that I have yet to figure out.

When the car is running the alt. light on the dash stays on very dim, the more things I turn on it gets a tiny bit brighter each time, the alt. is charging and I have swapped then out and still does the same thing, I have checked all of my grounds and they all seem to be good!

This issue came out of no where after we had a long stretch of really cold weather, I even put in a new optima battery thinking that could be it, but no!

Any insight would be greatly appreciated!

Thanks

Brent



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bk_burnout@hotmail.com (bk_burnout@hotmail.com)

Brent Kemi






Post generated using Mail2Forum (http://www.mail2forum.com)
Brian
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Lenny D.
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Post by Lenny D. »

Grounds, yes, and time to do this if you or someone hasn't already - make a ground wire to physically connect the alt. to the engine (use 12 or 10 ga. wire and SOLDER the connectors):

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HTH

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Post by bkbimmer »

Cool, thanks a lot guys, i will double check those things and let you know the outcome!

Brent
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Post by bkbimmer »

I cleaned all of the grounds and still has the problem, I unhooked the positive battery leed and placed a test light between it and the + terminal with the ingition off and I get a dim pulsing light from the test light, I have not been able to trace it out yet! Very anoying!!!
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Post by Lenny D. »

There are old posts regarding this that you are welcome to search. Keep your trouble light in between the + lead from that battery and methodically remove fuses one at a time to find the circuit that is 'leaking' volatge. Then you have to find what that circuit powers and disconnect them one at a time to find exactly what is causing the drain.
There are accessories (clock, radio upgrade, etc.) that use power all the time but is supposed to be miniscule. The emergency door unlocking feature comes to mind as well. There is a circuit that is supposed to de-energize after a few seconds that can become a power draw when it fails.
HTH

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Post by 1st 5er »

Experiencing a similar situation.
My alternator won't put out full current until high engine revs, 3500 to 4000 RPMs.
Then it'll maintain 13.7 +/- indefinitely, prior readings are in the 11.5 +/- range.

Good luck Brent...
Sherman

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bkbimmer
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Post by bkbimmer »

Lenny D. wrote:There are old posts regarding this that you are welcome to search. Keep your trouble light in between the + lead from that battery and methodically remove fuses one at a time to find the circuit that is 'leaking' volatge. Then you have to find what that circuit powers and disconnect them one at a time to find exactly what is causing the drain.
There are accessories (clock, radio upgrade, etc.) that use power all the time but is supposed to be miniscule. The emergency door unlocking feature comes to mind as well. There is a circuit that is supposed to de-energize after a few seconds that can become a power draw when it fails.
I already unplugged every fuse one at a time, disconected my stereo system and still no dice!

I even upgraded all the major grounds to 4ga. fine strand high current
cable and /highly modified an e34 120amp alternator and built custom brackets to make it all fit perfect.

I really don't get it, I am actually pretty good with electric/wiring and this has me stumped, my charging system puts out 13.8v all the way threw the rpm's!? WTF
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Post by 1st 5er »

Hey Brent,

Don't know if this'll help or not, but I figured out my issue.
I'd replaced all the ground wires without any positive results.
I then changed out the positive wire that runs from the alternator to the starter, problem solved.

Good luck as you continue your search...
Sherman

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Post by bkbimmer »

I will check it out, thanks

Brent
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Post by 1st 5er »

Well Brent,

It seems I lied earlier, not intentionally, but it was the truth at the time.
It turned out to be a lie upon the next start on Saturday afternoon.
I went out and started the car and it was back to it's old shenanigans.

But, the good news is, I have since solved the issue and permanently, I hope.

It seems my voltage indicator light was not connecting good in the instrument cluster housing.
As a matter of fact, I realized it wasn't coming on at all during this low charge situation.
Once I reseated it, it immediately came on full glow
and then went off once the car was started and the alternator started turning.

Evidently, a signal of some sort is passed through the idiot light
and back to the alternator, voltage regulator, or something down there
letting it know the indicator system is up and running so it's OK to discharge enough current
to run the components and recharge the battery as needed.

Sorry for the misinformation,
but it did start working properly after the wire was run from the alternator to the starter.
I guess coincidentally the idiot light must have been repositioned enough
from some sort of car movement to engage the system, at least temporarily.

I have now driven the car on a 100 + mile trip with several stops and restarts along the way
without any related issues whatsoever.

More GL wishes and keep us posted.
Sherman

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Post by Lenny D. »

You are exactly correct in your analysis of the idiot light having an integral role in the charging system. It serves as something of an 'exciter' for the alternator circuitry (somebody help with the proper terminology) and your refreshing the light CONNECTION (it's just a push-in bulb holder contacting the flimsy wiring bus of the cluster) allowed it to function correctly. Happy charging.

Geaux Saints!
HTH

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Post by 1st 5er »

Lenny D. wrote:
Geaux Saints!
X2

I was wondering why CBS showed that fan with the "Go Saints Go" sign near the end of the game.

:roll:
Sherman

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92 ///M5 (????)
91 ///M5 (T donor)
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86 535i (Snob)
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bkbimmer
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Post by bkbimmer »

Thanks guys, I still have not found the issue, I am thinking of taking it to an electrical shop to get it fixed, because if it keeps it up I will end up smashing the car into pieces :x
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Post by Lenny D. »

bkbimmer wrote:Thanks guys, I still have not found the issue, I am thinking of taking it to an electrical shop to get it fixed, because if it keeps it up I will end up smashing the car into pieces :x
Are you sure the bulb hasn't burned out? Just sayin'...'cause it has to be there (and work) for happy electrons (and drivers)!
HTH

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