Parasitic draw on battery, 96 Sierra

Wyley87

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So my truck has been sitting for a while. Put in a new battery since the old one wouldn't take a charge. Well, I've been chasing an alternator gauge problem and during the diagnostic found a parasitic draw. Except it doesn't drain the battery overnight or anything. Yet my draw has been 6 amps and won't go away unless i disconnect the wire from the back of the alternator. I took the alternator up to Autozone, its new and it tests all good. Ideas?
 

PenguinLTZ

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6 amp draw will kill a battery flat dead overnight.

put an amp meter in line and see what it is really drawing.
 

Wyley87

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That's what I did. Meter set on amps. Disconnected negative battery terminal. Then put the leads in line with the battery negative and negative cable.

I know that will kill a battery over night which is why this isn't making sense to me.
 

Wyley87

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143d714edd01f71056c258585775f5b8.jpg


Using an amp meter similar to this.
 

Black02Silverado

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How are all the other grounds? Make sure they are all clean and tight. If it is pulling through the alternator, then something is amiss in it. Will they exchange you for a new alternator?
 

Wyley87

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They will if it fails their "test". But it passed.

I'm taking the alternator to an actual alternator shop that comes highly recommend.

So this way I can totally rule it out of the equation.

All other grounds seem ok.
 
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Black02Silverado

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That is the way to go. I try to stay away from AutoZone or places like that when it comes to alternators. We have a shop here that has been in business rebuilding starters and alternators for over 40yrs and they have helped me several times. Matter of fact, they tested mine in my truck for free and couldn't believe it was still in good shape with 151k miles on it.
 

Wyley87

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Well I was going to just bring the truck up here but it needs stickers to be legal.
 

Zembonez

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If you disconnect the alternator and the draw goes away, it's obviously a fault in the alternator... To state the obvious.
 

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