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Odd dim problem

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Old Mar 6, 2003 | 01:15 AM
  #1  
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Kim
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From: Denmark
Question Odd dim problem

I did search, but couldnt figure out what the problem is, so here goes:
The other day when I drove home from work I noticed that my lights dims, like the voltage would fall and rise all the time. BUT this only happens when the engine is cold, when it has warmed up there is no problem at all.
Ive checked the voltage output which reads 14.5volts at 1500 rpms.
Can anyone please help me out since this seems to be my only problem right now and therefore it is extra annoying.
Thanks
Kim

Last edited by Kim; Mar 6, 2003 at 01:21 AM.
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Old Mar 6, 2003 | 03:00 AM
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From: Denmark
come on, someone must know
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Old Mar 6, 2003 | 03:29 AM
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...94% correct.
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From: High Texas
you can't get impatient about a problem when you post it at 1 am...most ppl sleep at this time.

Are you saying that you're voltage fluctuates while driving? That would cause the lights to dim and then brghten again. Also, do you have any kind of aftermarket stereo equipment that you run? Even a small amp will cause the voltage to fluctuate when teh bass hits.

My best advice to you is to check all of your grounds thoroughly. Then check and make sure you battery terminals are tight and clean. Also make sure the lead to your altinator is tight. If this doesn't help take the altinator and battery to Autozone and have them bench-tested. That's all I can say.
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Old Mar 6, 2003 | 06:18 AM
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From: Seattle
Which lights were dimming? If it was your gauge (illumination) lights it could be an indication of a failing headlight switch. The dimmer circuit (panel light control) is the weak link in an under-engineered electrical system.
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Old Mar 6, 2003 | 08:50 AM
  #5  
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From: Rohnert Park CA
Check your belt tension, and light switch if you have checked the alt output (should be at least 13.5 at idle and should not go above 14.6 under high RPM).

I also would upgrade the ground from the engine to the body and from the battery to the body, if you have not done so, as grounds on a 15+ year old car are usually shot.
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Old Mar 6, 2003 | 09:20 AM
  #6  
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Clean and check ALL Grounds. I have also noticed the main lead from the B+ terminal of the Alternator to have green corrosion inside the insulator the whole length of the harness. This corrosion can not help but to hinder current flow. .
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Old Mar 6, 2003 | 01:33 PM
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Thanks guys
FYI I dont have amps or other heavy **** in my car, but ill check out that light-switch, it sounds like it could very well be the problem.
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Old Mar 6, 2003 | 02:03 PM
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I'll bet you if you clean ALL your grounds the problem goes away
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