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finding a short

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Old 01-08-2008, 09:39 PM
  #1  
simpsonfan13
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Default finding a short

so my battery died again
im pretty sure as you guys said its prob a draw[&:].

my q to you now is how do find one?
not how do you know IF you have one but how do you locate it?
do you have to search thorugh all the wiring and conections in the
car by hand or is there an easier way?
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Old 01-08-2008, 09:48 PM
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mjr46
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Default RE: finding a short

did you put the meter on it and see how many milliamp draw it has yet??
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Old 01-08-2008, 09:56 PM
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WhiteWindsor
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Default RE: finding a short

I'm not sure what you've done to try and remedy the situation. Finding a draw in current is much a pain in the *** as it sounds. This wont answer your question but maybe give you some ideas. First have alt. checked. I did that and the 3g was fine. Second thing i did was charge the batt. up good to where it can start the car. My batt. is in the back. I dis. one of leads, don't matter which one and i pushed the button in the hatch that activates the dome light so it would not be on. I touched the lead back to post, and if you have spark then you have draw. The computer might be a slight draw anyway, i'm not sure, but i'm carb. Anyway i had spark and got lucky and found that the button inside glove compartment was stuck so it was staying on all the time. It was a small draw, but if i did not run car for two or three days it would be dead. THere are more complicated and surer ways to do it but you can use same method and pull fuses one by one untill you dont have a big spark when you touch terminal with lead. Hope this give's you some ideas. I just fixed mine tonite because i was tired of having to jump it off when i wanted to go for a cruise.
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Old 01-08-2008, 09:56 PM
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mjr46
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Default RE: finding a short

anyway once you establish that you have a draw what you do is you start pulling fuses until the milliamp draw drops to within spec.....once it does you have found the circuit that has the draw on it.....from that point you reference the fuse position to a diagram.......then you pull the wiring diagram for that circuit for example lets say you determined the draw was on the accessory/.radio fuse position......from there you'd pull that diagram and see how many circuits are tapped into that.....then you'd one by one unplug a component like lets say the radio pack connector while watching the meter and wait until the draw was removed then when it is..you've found the component that is shorted/staying on......the fuse that you pulled that had the draw on the circuit must be in position and draw present when troubleshooting so you can narrow down the draw to an area/component......also when working on a particular circuit look for places people may have tapped into the circuit to run a aftermarket accessory like a cd changer
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Old 01-08-2008, 10:10 PM
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Default RE: finding a short

you now mj now that you mention it the car does have an after market system installed.
its not connected though. well i just got a multimeter and will commence to testing by
the methods you guys discribed. i have a haynes repair manual so i think ill be able to reference
the diagrams.

btw the multimeter i got dosent have anything to clamp onto things with
just the kind you hold on what your testing (needle like).
and second what setting should i leave it on?
it has 2000u, 20m, and 200m
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Old 01-08-2008, 10:14 PM
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mjr46
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Default RE: finding a short

ORIGINAL: simpsonfan13

you now mj now that you mention it the car does have an after market system installed.
its not connected though. well i just got a multimeter and will commence to testing by
the methods you guys discribed. i have a haynes repair manual so i think ill be able to reference
the diagrams.

btw the multimeter i got dosent have anything to clamp onto things with
just the kind you hold on what your testing (needle like).
and second what setting should i leave it on?
it has 2000u, 20m, and 200m
whatever setting will render you amps....not sure what kind of meter your using as for the probes you are using...you need to find a way to secure one to the neg cable and the other to the batt post..otherwise the reading will be inaccurate or not at all
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Old 01-08-2008, 10:24 PM
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mjr46
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Default RE: finding a short

I usually use a digital multimeter and the setting on it is labled as such there is a commmon lead that gets plugged in = ground and the red probe I plug into the port with a "A" = AMPS.....then I turn the rotary dial on my fluke meter to a position that has sort of a U symbol backwards and a A beside that with a squiggly line above it... on my meter that's the amps function
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Old 01-08-2008, 10:36 PM
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simpsonfan13
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Default RE: finding a short

mine is a innova 3300 (auto zone special[8D])

an mine also has that greek u
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Old 01-09-2008, 05:06 PM
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Default RE: finding a short

You need to be careful when you hook up that meter, you are hooking it up in series with the car. If you have a draw of over 10 amps, you will probably blow the fuse inside the meter. Once you are hooked up, and you get a steady reading, then start pulling fuses like mjr described.
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Old 01-09-2008, 07:57 PM
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simpsonfan13
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Default RE: finding a short

well thanks everyone so far for all your help.
i really do apreciate it.

i actually had a buddy of my dads (mechanic for many years)
check it out with his meter. we found no draw.
i removed the alt and had it bench tested at a kragens and auto zone and it passed both times.
the guy at kragen even ran a check with their multimeter and nothing.

yet SOMETHING is draining the battery they guy at kragen said that one of the connections to the alt could be bad or loose.
i bought it cuz it was 11 bucks and mine DOES have a broken tab on a side (one of the tabs that secures its connection to the alt)
im going to start checking connections/cables tommrow

so anymore ideas guys?


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