LED conversion

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84Dually

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Hello everybody, first post here. Have gone through a few threads but havent found anything helpful to my situation.
Have had LED lights in all of my running lights + cab lights and never had an issue. Recently though i install a set of LED headlights and am now running into issues. My front fender sidemarkers no longer light up at all, my dash turnsignal lights remain lit, and both sides of lights flash when the turnsignal is activated. I have installed a set of LED flashers and got the same results. Im not the savviest electrically but any input helps!
 

dsteelejr

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Headlights and turn signals are on separate circuits, I don’t see how adding headlights would affect turn signals. You only had problems with the turn signals after installing LED head lights?

I still use sealed beam halogen headlights, but I had issues with the LED side marker/turn light when I switched to LED bulbs. Only way I could fix it was to use LED flashers, which I read you already have, in conjunction with LED side markers from LMC. Replacing the bulbs seems to work with everything except the side marker/turn lights. I had to get the complete, sealed LED unit.

 

84Dually

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Headlights and turn signals are on separate circuits, I don’t see how adding headlights would affect turn signals. You only had problems with the turn signals after installing LED head lights?

I still use sealed beam halogen headlights, but I had issues with the LED side marker/turn light when I switched to LED bulbs. Only way I could fix it was to use LED flashers, which I read you already have, in conjunction with LED side markers from LMC. Replacing the bulbs seems to work with everything except the side marker/turn lights. I had to get the complete, sealed LED unit.

Forgot i had done LED bulbs in my behind grille park lights. Removed bulbs and everything seems to be back to normal. Id like to be able to run them in the front aswell though.
 

TotalyHucked

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What do you have for tail lights?

For my '85, I have LED's everywhere including the tail lights. I had to wire in 50ohm resistors for each tail light and each marker light in the grille. So I have four 50ohm resisters in my truck. The LED flasher did nothing.
 

Jgonick

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Found these and thought they were excellent showing how the front park/dir lamp works with the side marker lamp.

Side marker lamps have current coming from different directions depending if lights are on or not.
LEDS (light emitting diodes) only allow current in one direction- unless modified somehow.

Front park/dir lamps have dual filament bulbs. The side marker lamp uses one of the filaments to go to ground and which filament it uses depends if the lights are on or not.
 

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geauxnow

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What do you have for tail lights?

For my '85, I have LED's everywhere including the tail lights. I had to wire in 50ohm resistors for each tail light and each marker light in the grille. So I have four 50ohm resisters in my truck. The LED flasher did nothing.
Did you wire it in series or did you place it across the line and load?
 

Tonimus

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Adjustable speed flashers always work in my experience. I have one in my motorcycle, a friends VW Bug, and a few others. The only "downside" is that it will not hyperflash if you have a bulb out. It will happily flash away, even driving just a test light.
 

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