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How to find a shorted wire?

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Old 07-06-2009, 12:29 PM
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Default How to find a shorted wire?

So last week we found that my car wouldn't start because the 15amp fuse under the dash was popping when ever the key was put in the on position. i unplugged everything under the hood from the main harness and pulled every fuse in the car other then the main eng fuses, and the ignition fuse to give power for me to see if the fuse would pop with everything unplugged. at this point i think it's coming from the main harness that is running to that 15amp fuse with a black/white wire but the wiring diagram shows that it the black/white wire runs into 1/2 the cars wiring systems.

there has to be a trick or secret to finding a shorted wire in the car.
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Old 07-06-2009, 01:15 PM
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1- Disconnect the battery (-) terminal.

2- Remove the fuse and replace it with a jumper wire.

3- Re-connect the battery.

4- Extinguish the fire. Whichever part caused it is where the short was.
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Old 07-06-2009, 01:34 PM
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^What Joe said.

Note: Be sure to use a large enough gauge jumper wire.
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Old 07-06-2009, 01:50 PM
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anything with less setting fire to a random part of my car?
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Old 07-06-2009, 01:58 PM
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Make a list of everything that fuse powers. It's not a very long list, if I recall correctly. It's not a thick wire, so it's mostly just relay triggers and such. Once you've done that, start with the easy stuff and check connectors you can see.

If it's not easy, be warned that this may require you to pull the dash and un-loom the entire harness. It's a bitch.
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Old 07-06-2009, 02:08 PM
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My nightmare. Luckily my issue was just a spike issue and I installed a 15A breaker and went on my way. It kicks off and back on without me ever noticing, for now anyway. I was tempted to run a jumper wire and wait for something to burn up, but I didn't want it to be under the dash or something. I had the dash out to look for it and saw the main wiring harness/loom and said **** it and put it back together. I would absolutely have a break down trying to sort through those wires.
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Old 07-06-2009, 02:10 PM
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on a 2000 car it's

cooling fans
air conditioning
engine controls (everything under the hood)
computer
data lines
supplemental restraints

no clue on a 2002 and i can't find a diagram for a 01+
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Old 07-06-2009, 02:15 PM
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oooo. Good luck!
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Old 07-29-2009, 03:17 PM
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Rear o2 melted to the mid pipe, fried my gauge ribbon and blow some fuses. car lives again but is oddly running leaner then before...
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Old 07-29-2009, 03:25 PM
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damn dude, that sucks. I had fun at your party btw. Crunk az *****, nugger.
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