Weird electrical problem

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theother1wstolen
Posts: 263
Joined: Mon Jan 15, 2007 5:23 am
Car: 92 240sx Coupe SE

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So I somehow got a major short in my main power wire from the alternator to the battery (stupidly didnt have it fused) it melted the insulation on the wire, and now the alternator isnt charging but even if i let the car run with jumper cables hooked up to the battery, the car will start, but the gauge cluster doesnt come on at first then after running for a minute it pops on, any ideas on what could it could be?


Vegascorbin
Posts: 732
Joined: Sat Nov 24, 2007 9:56 am
Car: 1990 240sx dirt track race car

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Sounds like you fried your Alternator. Fix the melted wire and then the Altenator. Put the Fuse back in the circuit.

Find out what caused the melted wire to start with.

After that re-test and see if that fixed the problem.

Whenever you have a problem start by fixing those things that you know are bad even if you don't think it is related. More often then not if you fix what you know is bad, other problems will go away. Also look at it this way, you hav eto fix them anyway so youare not wasteing any time.

theother1wstolen
Posts: 263
Joined: Mon Jan 15, 2007 5:23 am
Car: 92 240sx Coupe SE

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luckily my alternator has a lifetime warranty, so im getting that in tomorrow, and i bought a new cable, ill keep you guys posted. -crosses fingers-

theother1wstolen
Posts: 263
Joined: Mon Jan 15, 2007 5:23 am
Car: 92 240sx Coupe SE

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i put my alt in today, its charging ok, but ive still got a couple electrical issues, the gauge cluster isnt always coming on with the key just in the on position, it did once tho, and the voltage for my radios 12+ constant for some reason drops to 2 - 3 volts when the car isnt running, suggestions?

theother1wstolen
Posts: 263
Joined: Mon Jan 15, 2007 5:23 am
Car: 92 240sx Coupe SE

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it appears as if the items running off of the acessory and constant +12v circuits arent getting the proper voltage unless the car is actually running, and the battery is showing 12v at least when the car is off, so what in the hell could cause voltages to drop only on certain circuits, and only when the car isnt running?

aquariustiger
Posts: 55
Joined: Sat Mar 24, 2007 3:44 pm
Car: 1989 nissan 240sx
1991 240sx

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had a similar problem a while back...see if this helps:

zerothread?id=311517

theother1wstolen
Posts: 263
Joined: Mon Jan 15, 2007 5:23 am
Car: 92 240sx Coupe SE

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much appreciated and that link did tell me one thing, someone ghetto rigged my fuse (the previous owner of this car really rigged a lot of wiring) ive had it for 6 years now and never realyl knew lol, but anyway its not really the same problem, the alternator is charging the bat, and my gauges and radio and everything works fine when the car is running, but none of it is getting the proper voltage when the car is off, or just on accessory, or even with the key turned to on, it HAS to be running.also, its not taking a minute for the gauge to come on anymore, everything immediately starts getting the voltage it should once the car is started.
Modified by theother1wstolen at 6:22 PM 2/20/2008

got chub
Posts: 1843
Joined: Sun Aug 19, 2007 3:10 am
Car: pearl white 95 240sx

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the same thing happen to me twice. i hit the hot side of the alt and shorted out to the battery. it did everything you said melted and all. it was my 75A fusible link that was blown. i replaced it and then about a month later it did it again. this time i replace the fusible link and the part that was melted from a junk car. it ended up killing my optima red top battery with a dead cell. all in all i paid under ten buck from the dealer for the fusible link and 14 for the front part of the harness that was melted. hope that helps you and GL

theother1wstolen
Posts: 263
Joined: Mon Jan 15, 2007 5:23 am
Car: 92 240sx Coupe SE

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ill be damned, when i stuck my probe it in, it worked fine, and if i jiggle it it works, lol. (referring to the fusible link) thank you ALL OF YOU, i <3 nico


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