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Discussion Starter #1
I saw on here how to do this before but can't find it....anyone....anyone.
 

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I don't think you can find a short with a test light unless you can find the short. Electricity isn't going to flow through a bulb when it has a much easier path back to ground.
 

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Discussion Starter #3
It was something like put a test light on the alt or battery on a car....if it lights up there is a current through it and a short soewhere draining the batt....pull fuses one by one and when the light goes off, you have found the circuit with a short......but I cant remember where to put the test light.
 

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Maybe I'm way off, but wouldn't you remove the positive from the battery.. put the test light between the + and battery cable.. Pull all fuses and put them in 1 by one and when it lights up you know where your draw is?

:shrug like I said I could be wrong..

and this really should be in the noobie questions..
 

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Ah, the procedure you're referring to is to help find a draw that is draining the battery while the vehicle is off. You disconnect the negative battery cable from the battery and attach it to the positive side of the test light. Then you connect the negative side of the test light to the negative battery terminal. If it lights up, something's drawing power. Then start pulling fuses until the light goes out.
 

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Ah, the procedure you're referring to is to help find a draw that is draining the battery while the vehicle is off. You disconnect the negative battery cable from the battery and attach it to the positive side of the test light. Then you connect the negative side of the test light to the negative battery terminal. If it lights up, something's drawing power. Then start pulling fuses until the light goes out.
This is pretty much the idea. Although when I do it I use the positive cable and post with test light in between, but either way will produce the same results. The light should light up regardless if there's a big draw or not. If the light lights up nice and bright (as if you placed it across both positive post and negative posts), then there's a draw. It "SHOULD" light up dim due to your presets in your radio and memory for your clock. If it lights up nice and bright, start pulling fuses until the light goes out or back to dim. Once the fuse for the problem circuit is found, then figure out whats on the circuit and start investigating those items.
 

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Actually, the test light needs to go on the negative side for at least one reason, but I always recommend putting it on the negative anyway due to the size of the inductive arc caused by hooking the positive cable back onto the positive terminal. Doing it on the negative side produces a much smaller arc, reducing the chance of a battery explosion.
 

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Why would you need to use a test light instead of a cheap Radio Shack multimeter?

I can't imagine how you could find a short with a test light. The test light requires power to light.. there will be no power with a short.
 

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I can't imagine how you could find a short with a test light. The test light requires power to light.. there will be no power with a short.
Go try it.Its works
hook it up ether way,and for a test open a door ,it will light up bright.
 

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Mud God - R.I.P.
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Pull the + post cable off the Bat. hook the ground end of the test light to the Bat,the prob end the the cable.The light will be off or dim if NOTHING is on or there isn't a short.If you open a door the light will shine BRIGHT.Same if theres a short.
 

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Pull the + post cable off the Bat. hook the ground end of the test light to the Bat,the prob end the the cable.The light will be off or dim if NOTHING is on or there isn't a short.If you open a door the light will shine BRIGHT.Same if theres a short.
So by opening the door you verify that you have continuity from the battery through your test light to the battery cable? This helps you find a short how?
 

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Mud God - R.I.P.
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That doesn't help at all.
But will show you if the light is bright or changes.
If the light is bright,with EVERYTHING turned, off doors closed,there's a draw"possible short",you can then pull one fuse at a time till you find the one that changes the light.Then research what all is on that circuit.
 

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I guess it depends on your defenition of "short". My defenition would have blown the fuse in the cigarette lighter circuit.
 

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I guess it depends on your defenition of "short". My defenition would have blown the fuse in the cigarette lighter circuit.
That wouldn't be a short.. That would be an "Open" Huge difference..

That's why you're not comprehending the explination.
 

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ok i a having similar problem and i went through the process of the light test above and no matter fuse was pulled light never went out.
door switch tape closed.
 
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