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Old 05-25-2015, 10:32 PM   #1
dixiethecustomcamper
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Headlights still wont work

Hey guys, I made a thread a few weeks ago regarding my headlights not working. everyone suggested it was the dimmer switch and the wiring involved. I have now replaced the dimmer switch and the little 3-prong plug that it attaches to on the wires. I cut the wires and stripped about a half inch of insulation on the new plug and old wires to twist them together. I was planning on soldering the wires (I have never done soldering but I am a very confident learner and believe I have a pretty good idea of what to do) but my soldering iron is a small battery powered piece of junk that only has about 3 volts of juice. it wasn't even hot enough to melt the solder to prep the iron. I have all of the wires connected (tied) and wrapped with electrical tape, brand new dimmer switch and plug, and the headlights still will not turn on. I drew a diagram of the wires looking down on the dimer switch it reads GREEN BLUE BROWN in that exact order. any ideas as to where I should troubleshoot next? Does my diagram line up with what you guys have or could I have just made a simple error in my wiring...? thanks everyone for the responses I really appreciate the advice
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Old 05-25-2015, 10:37 PM   #2
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Re: Headlights still wont work

I just went through similar and it ended up being the headlight switch in the dash.
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Old 05-25-2015, 10:40 PM   #3
dixiethecustomcamper
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easy part to find?
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Old 05-25-2015, 10:49 PM   #4
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Re: Headlights still wont work

You can probably still get one at the parts store. I had an extra here that i used.
You are sure the bulbs are good?
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67 gmc custom lwb dakota truck. Sold...And bought back
69 swb 4x4 project (in progress)
70 c-10 lwb texas truck
70 4x4/BB/bkts/posi/tach(retired)
70 swb (wifes)
70 jimmy camper
71 K-5 factory 2wd
71 cheyenne 4x4/tach/posi/ plow rig
71 Cheyenne20 BB, buckets, tach, tilt, 4 speed
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Old 05-25-2015, 11:42 PM   #5
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Re: Headlights still wont work

Yes, the headlight switch should be easy to find. And be sure to beg, borrow, or buy a decent soldering iron, some rosin-core solder, and heat shrink tubing. Twist & tape won't be a good connection and won't last very long. Might also have to break out a VOM or at least a test light and start chasing voltage (or lack of it).
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Old 05-26-2015, 12:56 AM   #6
VetteVet
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Re: Headlights still wont work

The blue wire to the dimmer switch is the power wire when the headlight switch is pulled out. If you have power on the blue wire when the switch is out and none when the switch is in, then the switch is OK and is doing what it's supposed to do.

The dimmer switch merely selects power from the blue wire to the brown or green wire depending on whether high or low beams are desired. If you get no power from the blue wire to either the green or brown wire or both, then the dimmer switch is defective. The dimmer switch is not grounded so that is not a factor. You can jump a wire between the blue wire and the green or the brown wire to bypass the dimmer switch. If you get lights, then the dimmer switch is bad. If you don't then you may have a bad connection inside the firewall block that connects the green and brown wires with the green and brown wires on the engine side of the firewall block.

You can pull the plug on the left headlight and check for power on the green and brown wires in that plug to see if power is getting to the headlight. The left headlight plug has 2 each brown and green wires to feed both lights with high and low beam power. If you get power there, then the firewall block connections are good and the problem is in the head light.
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Old 05-26-2015, 12:58 AM   #7
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Re: Headlights still wont work

Name:  image.jpg
Views: 71
Size:  74.9 KB lol, I remember that thread, I will suggest again that you test for power before replacing the part. I thought I made it pretty easy for you telling you which wires should have power, most people would just show you a wiring diagram and say read this, I've seen it happen many times. You need to get a test light, they are about 5 dollars at any parts store and can tell you which wires have power. If there's anything you don't understand about that just go ahead and ask. Most people are happy to help. That said, if you want some more speculation, yea it's prolly the switch. Seriously though, just test it out man! Good luck bud, hope you get er fixed this time!
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Old 05-26-2015, 01:07 AM   #8
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Re: Headlights still wont work

Lucky you, VetteVet just showed up. Here's some more help curtesy of VetteVet. Bet he doesent even remember posting this but it helped me out in my time of need!Name:  image.jpg
Views: 60
Size:  87.1 KB you can find some good stuff searching through those old threads, thanks Vet!
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