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Old 11-24-2002, 09:12 PM   #1
BUXMAN66
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electrical woes?

what would cause the drivers side headlight to become dim? i've been tinkering 'round w/ the electrical system lately,(new 1 wire alt.,new battery cables,grounding straps to body and frame)replacing different things.had been experiencing a loss of battery voltage but come to find out i had no grounding straps to speak of ,so replacing them seemed to take care of the inability of the alt.not producing any voltage to keep my battery charged.but......even after replacing these parts i've noticed a slow voltage drain on my battery.at engine idle the alt. is making 14.5 volts back to the battery,battery is showing 14.5 on positive battery post at engine idle. with engine shut off,12.5 volts at battery positive post.after sitting w/ engine off for approx.1-2hrs.volts are showing 11.9-12 volts actually not enough to turn over engine. no lights are on,stereo's,interior light......zilch.now what in the he!! could be draining the battery?no circuit's have been left on! what really got me was the drivers side headlight going dim which i had never noticed b-4,could this be connected,somehow?(i did jiggle the plug into the headlight,made no difference.)sorry for the long post,guys!
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Old 11-24-2002, 09:58 PM   #2
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Buxman - first, thanks for your previous post on the grounding straps. I had the same problem - new alternator, voltage regulator, battery etc., but still drained daily. Hooked up grounding straps and solved problem.

This one you have has to be a shorted circuit somewhere, draining electricity. It would have to be a wire that remains hot after you turn off the switch, like the dome light wire. Have you checked the condition of your wires under the door sills? That's a place where wires can get rubbed raw and short out (dome light wire, for example). Good luck!
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Old 11-25-2002, 01:38 AM   #3
BUXMAN66
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thanks for responding 72k10! 'ppreciate it! the only problem is how do you go about finding this mysterious gremlin?isn't it kinda like looking for a needle in a haystack?electrical troubleshooting isn't exactly my forte! what would i use a tester light?......some thing that would show that voltage is present .......even when it shouldn't be?........like only voltage should be present only when you turn on the domelight for example?thanks for any and all responses!
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Old 11-25-2002, 02:27 AM   #4
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anyone got any ideas what to look for?
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Old 11-25-2002, 07:47 AM   #5
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Buxman, hopefully someone who knows what they're talking about will respond. The only thing I know to do is the visual inspection - look for bare wiring. Usually works pretty good for me, and doesn't take that long once you start. I think there's some method using an ohm-meter, though, that will tell you if a wire is shorted / broken??
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Old 11-25-2002, 08:28 AM   #6
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Talking

On your headlight, it almost has to be a ground problem, but try unplugging and plugging the headlight. Sometimes it is really hard to get the contact at the light.

On you battery problem, what you describe sounds like a bad
battery. What happens to the voltage if you crank it while reading the voltage?

Jim
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Old 11-25-2002, 08:45 AM   #7
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I would use a test light. Take the positeve terminal off the battery, touch the test light to the cable and then the positive terminal, if it lights up you have a short. Then start on your fuse block and remove each fuse and check between the terminals of the fuse block, if it lights up that is the circuit you need to check.
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Old 11-25-2002, 01:21 PM   #8
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I think Jim may have your solution. Try unhooking the battery after you shut off the engine and then test your voltage. Check it again in an hour and compare the readings. If it drops, your battery is shot.

On the headlights, make sure the ground is in good condition with no rust under the ring terminal. If there is not a star washer on it, you may want to add one. Also, clean the headlight terminals with an emory cloth and WD-40 then add som dielectric grease (if you have it) before you mate the connector to the headlight.

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Old 11-25-2002, 03:46 PM   #9
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Sounds like they all got you going on the right track. It is a matter of divide and conquer. Or isolation if you want a more technical term. I know with my truck it proved difficult when I had some electrical problems when I first got it. Some brainiac decided that as wires got bad new ones should be run in all different and funky ways but they left the old ones inplace disconnected. But I found one that wasn't completely disconnected and It not only drained the battery but killed my alternator to by making it work to hard. The biggest problem with finding that one is it was shorting me out only some of the times at other times it wasn't shorting me out! Good luck! Just thought you might want to know about my experience with my trucks electrical system.

David
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Old 11-25-2002, 04:09 PM   #10
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Sounds stupid, but swap headlights, one may be shot. Tim m has it right, use any small 12v light between the + on the batt and the cable, isolate the drain to 1 fuse circuit, then unplug each device on that circuit until light dies, that's where the problem is.
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Old 11-25-2002, 04:56 PM   #11
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The test light is a good tool for troubleshooting, but remember that you can get a "false indication" by ringing through the windings of a fan motor, alternator, light bulb, etc.

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Old 11-25-2002, 06:50 PM   #12
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I would test the battery before anything else, I think jim hit it on the head I think you have a bad battery. It would take a major drain to run your battery down in that short a time. If you had a really good battery you could leave your headlights on that long and it would still crank. And at 11.9 volts it should still crank but it might be a little slow.
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Old 11-26-2002, 02:37 AM   #13
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thanks guys for all the replies!got my work cut out for me!will keep yun's posted what i find.
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