Saturn Alternator amp draw

All the beeping, zapping bits

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jeffball610
Too Much Time on His Hands
Posts: 619
Joined: Wed Feb 22, 2006 5:29 am
Location: Las Vegas, NV

Saturn Alternator amp draw

Post by jeffball610 »

After my swap, I noticed I was getting a dead battery within a day or two even though it was putting out the required power when running. I did an amp draw test and found a 4.5 amp draw from the alternator "sense" wire hooked up the alternator "F" post. Disconnecting it gets rid of the draw, but also does not allow the alternator to put out the required amperage to charge the battery. A quick search says some alternators could have a bad diode, but this is a new unit and "should" likely work just fine.

So I'm at a loss with my current knowledge base. I can get the alternator checked, but if it tests good, then what are some likely culprits to this amp draw? I know my grounds are good. My wiring should be solid. Do I even need that wire? Some sources say "single wire", but I'm not getting 14v when running without it. Grrrr.

I did find this article, but not sure how accurate it is since I haven't seen anyone else doing it this way.
http://www.dsmtuners.com/threads/import ... 44794/[url][/url]
Do it in a Datsun!
1972 Datsun 510
7-bolt 4G63T, EVO 9 pistons and rods, Garrett GT3076R, "flipped" stock intake, Toyota R154, Z31 R200 w/ CVs
jeffball610
Too Much Time on His Hands
Posts: 619
Joined: Wed Feb 22, 2006 5:29 am
Location: Las Vegas, NV

Post by jeffball610 »

Hmm. People aren't very active on here anymore. I figured out the issue. The "sense" wire needs to be attached to the charging side of the circuit instead of directly to the battery as I had initially set it up. Simple issue. It was drawing nearly 4 amps while sitting.
Do it in a Datsun!
1972 Datsun 510
7-bolt 4G63T, EVO 9 pistons and rods, Garrett GT3076R, "flipped" stock intake, Toyota R154, Z31 R200 w/ CVs
turbostellar
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Joined: Sun Jan 07, 2007 10:09 pm
Location: Bowmanville, Ontario Canada

Post by turbostellar »

Glad you figured it out
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