1983 headlight issues

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squarebody4life

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Georgia
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Alan
Truck Year
1983
Truck Model
K20
Engine Size
6.2j code
In the past couple of months I added the lmc headlight harness with relays to take the load of the circuit. That worked great and gave me slightly better lighting at night.
The next thing I did was to add the H4 conversation kit from parts to go. That kit contained the 4 glass beams and 4 H4 3 pronged lamps.
Now here’s the weird part.
The headlights worked great before the swap.high beam all 4 lights on bright. Low beam just the 2 lit.
After plugging in the new setup on high beam all4 light up but , low beams are dim and highs are bright.
When I switch it to low beams all 4 light up lows are bright but, high beams are dim.
This should have been a simple plug and play.
I checked the grounds and they are all good and clean.
Any thoughts on what to do next? Could my relays have gone bad?
Pics are below to hopefully show what I tried to explain
 

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PrairieDrifter

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It seems like you have low battery voltage. or the prongs on the new bulbs are in a different orientation. So you'll have to "repin"
 

squarebody4life

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6.2j code
I’ll try repinning next Ty.
 

WP29P4A

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I would identify the pin configuration you have before changing anything, then I would figure out the pin configuration required for the bulbs. Then I would make the changes. I just ran into this problem on a jeep rock crawler my client has been paying me to fix. Got more than 40 hours invested in repairing ALL the wiring issues created by the several mechanics that have worked on the jeep, plus the V8 conversion and several sessions of adding the latest electronic gizmos and lights.

I was asked to do a simple headlight swap while I was correcting the wiring, should have been "plug and play". The stock headlights worked properly. When I plugged in the new LED headlights, they didn't act the same as the originals. One was on high the other on low, when I plugged in the first bulb it was normal brightness, then when I plugged in the second bulb, it got brighter.

This was a HUGE red flag, never do you get brighter by connecting more load. (more bulbs) This was the point where I got out the test light and verified what was happening on each connector. On one bulb they had the low and ground switched. Incandescent bulbs are NOT polarity sensitive, LED bulbs ARE polarity sensitive.

The voltage was going to the low filament on the driver side, then instead of going to ground it went to the passenger side high filament, then to ground. One light would be on high while the other was on low, and when you would flip the high/low switch it would reverse which light was high and which was low.
 

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