Headlights and blinker problems. Again!!

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Rusty Nail

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Ya!

Grounds.
Are maybe switched?
Turning your brights on _ grounds the circuit _ and turns the lights off?

Made me think of this squarebody H4 conversion wiring diagram. It's easy to look at and would be easy to see.
One side is lt.blue and the other is green? Anyways might wanna check it out...good luck!

Pix?
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You don't gotta buy nothin - I wonder if you maybe have a couple of wires in the wrong spots is all.
 

RanchWelder

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I rewired with four 3-wire lamps. I used two 40A relays and 12ga wire for the lights and 14ga for the ground circuit, in a custom made harness.

I bought the ceramic connectors with the heavier gauge wires, since some came with sub standard wires. This 87 had a pair of lights with 2 poles and a pair with three. I thought I could transfer the entire system to 3 pole lights, and configure so 4 high 4 low. 4 lights on no matter what.

The problem is, when the lights are on the low beam circuit, they are very dim. All 4 lights work, just dim. On high beam, they are all very bright, (as expected). Your reverse ground diagram made me think my 4 headlight system cannot be actually set up for proper function, without a switch to reverse the ground, when on low beams.

The GM switch circuitry and the way the system wires the wipers, gets confusing.
My lights work, however my imagination on what would work and the way GM actually wired the switch functions might be different.

I wonder how many guy bought a truck with a 2 light configured switch and had somebody swap the core support and try to alter to 4 lamps, or vice-a-versa?

I'll bet the switches are not comparable and the ground functions are screwing up a bunch of people's attempt to upgrade or modify, in addition to your diagram?
 

Grandpas_Truck

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I had a very similar problem on my 86. Turn signals would work, but when I turned the headlights on, the turn signal indicators on the dash would light up, and the running/turn signal lights would be very dim, could hardly tell that they were on. It ended up being both turn signal sockets were bad. The ground terminal on the inside of the socket had broken off causing a poor connection to ground. I would check those.
 

74Blaze

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My Blazer had a similar issue when I bought it. I went through much (ground wires, turn signal switch, headlight switch...) trying to figure it out. I decided to replace all the bulbs one at a time. When I replaced the left, rear bulb everything started working fine. Upon inspection, one of the two filiments inside the bulb broke and shorted against the other. Stupid little thing that cost me a lot of time, money and frustration.
 

82sbshortbed

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The new headlights switch and knob came in. It broke so needed to be replaced anyway. But I'll check the last two suggestions too. Thanks for the help y'all.

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82sbshortbed

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Y'all ain't gonna believe this. Ordered the 4x6 led headlights and they came in today. So I pulled the front grill out to make it easier to test and also install the new leds. Pulled the blinker sockets out and set grill aside. Noticed they had a clear bulb in the Dr side. So I put a new amber one in checked it and it. Works great.

Then decided to turn the lights on and start testing. Now it still blinks with the lights on. Wtf? Guess it was a bad bulb. Lol

But the brights still doesn't work. So more tests coming up.
 

74Blaze

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Damn, I hate being right all the time.

Glad that you got it fixed. Those stupid little issues can be very hard to diagnose.
 

Scott91370

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Possibly a broken element and that element was touching the other element or the ground part of the bulb.

Electrical - gotta love it!
 

82sbshortbed

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Ya!

Grounds.
Are maybe switched?
Turning your brights on _ grounds the circuit _ and turns the lights off?

Made me think of this squarebody H4 conversion wiring diagram. It's easy to look at and would be easy to see.
One side is lt.blue and the other is green? Anyways might wanna check it out...good luck!

Pix?
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You don't gotta buy nothin - I wonder if you maybe have a couple of wires in the wrong spots is all.

This helped me get the leds to work. When I just plugged it in no work so I moved the ground to the middle prong ant it lit up to top two lights but, the lower lights don't work. No power when I turn bright lights on or not.

The lower lights are just two wires also not three like the top ones.

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Thanks for yalls help I'm slowly getting better. I'm not the best at this. Lol
 

Ricko1966

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First thing I usually do when something doesn't work. Grab a 12v test light,bulb style,not led. Hook 1 end of my light to the component hot side touch the other end to the component ground ? Light on?bad component. No light, move your test light negative,to battery negative. Got light? The ground is bad. No light, back track your hot lead. Those are basics,volt drop tests are sometimes necessary,but the above gets the job done 90 percent of the time. If you make your own test light using a head light sealed beam,you can even eliminate the need for a volt drop test,most times.The head light has more draw than the test lamp.
 
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Rusty Nail

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Uhhh.

What kind of blinker canister have you got? The factory 1984 blinker canister will not work LEDs correctly I bet you will need a different blinker can.
Welcome to led. :) :dancingpoop:

Research and see - reckon that is your next step? About the LED blinker can for your fuse box? some ship...who knows? :shrug:
hyper blinker / canbus stuff / resistors and ish

The blinker is stuck to one side in the can because the voltage is too high to allow the switching between grounded and not - that's why some of it works when you move the wire. Might have to move it back to fix it. eh? guessing
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fourteen bucks for electronic flasher relay?


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82sbshortbed

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Noticed also that when checking with a test light(clipped to ground) that the tan or green wire lit the bulb better than the other one. I'll have to look again to remember the color. One was dim and one was Brite. So I'm guessing it's getting more power to one of the wires.

If I click on Brite lights the power turns off to both wires. I might need a relay or some kinda conversion kit. I've seen a video on YouTube where he was doing one similar to mine but had two different boxes he hooked up. It was a different brand than mine but work the same I'm sure. It was his first video and kinda long and slow to get to the point so I didn't finish it. Lol

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I'm gonna finish it today even though they're different from mine I might learn something that will help me. Mine also has the amber halo that hooks to the front blinkers so they flash with the blinkers. So we'll see how it goes. I have some new pigtails coming too.
 

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