Help wiring LED front turn signals


Gobucks43112

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Hi guys. Just finished putting tube fenders on and need help wiring in the turn signals.
02 TJ, already have front LED’s and tail light LED’s.
The lights that came with the fender are 2 wire, red and black and my factory socket is 3 wire.
Any help with how to wire would be greatly appreciated, including any new relays or any other parts needed.
Thanks in advance
 

jscherb

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The polarity to the factory TJ side marker alternates depending on whether the headlights are on or not. To make a single function LED work with either polarity, a bridge rectifier can be used (I did this drawing when Radio Shack was still in business so it includes a Radio Shack part number for the bridge rectifier)

LEDBridgeRectifier_zpszdmhw6so.jpg


And for the front-facing turn signal/running light, any single function LED can be turned into a 2 function (dim and bright) with a resistor and 2 diodes:

LED2TerminalWiring_zpsq7wqh4xf.jpg


 
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Gobucks43112

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Thanks for the post. Trying to make sure I understand this.....
I’m going to get rid of/not use the side marker light (nowhere good to mount it).
My new LED turn signal (front facing) has a red and black wire. Use the red as a ground (like white wire in above diagram) and split the black wire in two with a diode on one of the two?

And then connect these 3 to the 3 factory wires?

sorry, but horrible with electronics
 

jscherb

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Thanks for the post. Trying to make sure I understand this.....
I’m going to get rid of/not use the side marker light (nowhere good to mount it).
My new LED turn signal (front facing) has a red and black wire. Use the red as a ground (like white wire in above diagram) and split the black wire in two with a diode on one of the two?

And then connect these 3 to the 3 factory wires?

sorry, but horrible with electronics
Whichever wire on the LED that is the negative terminal goes to ground. The turn signal wire on the Jeep goes to the wire drawn in red in the drawing and the running light wire from the Jeep goes to the black wire in the drawing with the resistor. Then the wire after the resistors goes to the positive terminal of the LED.

If you experience "fast flash" you'll also need a load resistor or an LED-compatible flasher module, a search will turn up lots of info on solutions for fast flash.
 
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Gobucks43112

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Still having trouble...... tube fenders are on. Parking lights and side marker lights are wired up and turn on as they should. But my turn signal lights on the dash light up as if there is a bulb burnt out?? Got a new EP27 5 pin LED flasher and no luck.
Any thoughts or help is appreciated. Thanks
 

DougB

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I am about to follow Jeff's schematics above after installing my GenRight highline fenders as their LED kit comes with 2-wire front and side LED lights.

FYI - HobbyTown is Radio Shack Express now and carries some items. My local HobbyTowns have the rectifier mentioned above in stock. They also have some diodes and resistors. Hoping this works as Jeff has shown in his video. That's exactly how I want mine to function.
 

DougB

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@jscherb @Steel City 06
Is there a reason both front turn and side marker shouldn’t/couldn’t be run off the two diodes and resistor circuit shown above? This is with both lights being 2-wire LED. I understand both would flash at same time vs alternating which I suspect Is what happens when using the rectifier in the side marker.

Thanks
 
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Steel City 06

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@jscherb @Steel City 06
Is there a reason both front turn and side marker shouldn’t/couldn’t be run off the two diodes and resistor circuit shown above? This is with both lights being 2-wire LED. I understand both would flash at same time vs alternating which I suspect Is what happens when using the rectifier in the side marker.

Thanks
You would need to change the type of bulb in the front fender lights to a 2 wire bulb. If you're replacing the front fenders entirely, it may make sense to do so. (However, the work to retrofit 2 wire bulbs into the factory 3 wire front sockets would be a waste of time.)

It will affect what size of resistor you need if you use the same resistor for both lights. I recommend buying a kit of 1 watt resistors and playing around with them to get the brightness you want. (You could be really fancy and use a dashpot if you're bored.)

If you are replacing the lights in all four locations (fenders and flares), it would be far easier to simply buy 3-wire turn signals and running lights.
 

DougB

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You would need to change the type of bulb in the front fender lights to a 2 wire bulb. If you're replacing the front fenders entirely, it may make sense to do so. (However, the work to retrofit 2 wire bulbs into the factory 3 wire front sockets would be a waste of time.)

It will affect what size of resistor you need if you use the same resistor for both lights. I recommend buying a kit of 1 watt resistors and playing around with them to get the brightness you want. (You could be really fancy and use a dashpot if you're bored.)

If you are replacing the lights in all four locations (fenders and flares), it would be far easier to simply buy 3-wire turn signals and running lights.
Thanks for the reply. I bought the 1k ohm 1W resistor per @jscherb but saw others have used other sizes so I have 1/2W in smaller sizes. Running it all off the front marker light seems better but wasn’t sure the electrical side of it.

I have GenRight high fenders and using their LED kit which is 2-wire front and side lights. There are 3-wire LEDs available for the front (3/4” round) LED but the side marker LED I am not able to find anything as small as what GR uses. They also provide brackets so makes it easier to use their lights vs go more custom finding 3-wire lights and making a new bracket.
 
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DougB

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Here’s what I ended up doing and it functions exactly like stock and Jeff’s video.

A friend had some 3/4” round LEDs for the front that are 3-wire so connected those in using the factory wiring and it operates fine.

Used the rectifier from Radio Shack on the side marker 2-wire LED and it alternates with the front LED during blinker when running/parking lights are on and dims for running/parking lights. It turns off between blinks just like the factory side marker light. When running/parking lights are not on it flashes with the front light during blinker or hazard.

I’ll get photos up as soon as I get the wiring cleaned up as it’s all way too long presently.

Thanks @jscherb and @Steel City 06 for the circuit explanations.
 

Jerry Bransford

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Why is it so important to run LED bulbs in the turn signal circuits not designed for them that some will go to great lengths to like bridge rectifiers and other odd diode circuits to try to get them working?

I have the electronics background to make them work by installing a bridge rectifier for each turn signal bulb but why? What is the attraction to an LED bulb when the OEM incandescent bulbs let the circuit work as designed without modifications few understood well enough to get working.

I have LED headlights because they reach out further but they plugged right with no circuit modifications needed.

For turn signals that get totally jacked up with LED bulbs without complex modifications beyond most? I just don't get it.
 
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DougB

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Why is it so important to run LED bulbs in the turn signal circuits not designed for them that some will go to great lengths to like bridge rectifiers and other odd diode circuits to try to get them working?

I have the electronics background to make them work by installing a bridge rectifier for each turn signal bulb but why? What is the attraction to an LED bulb when the OEM incandescent bulbs let the circuit work as designed without modifications few understood well enough to get working.

I have LED headlights because they reach out further but they plugged right with no circuit modifications needed.

For turn signals that get totally jacked up with LED bulbs without complex modifications beyond most? I just don't get it.

I agree, if one has stock fenders and light housings. For those changing over to tube fenders LEDs are generally the only option offered. Poison Spyder offers a front 3-wire LED so there’s no hassle with its wiring and function. Not sure what they offer for the side marker light. GenRight offers 2-wire front and side LEDs. Yes, I could have just wired it up like GenRight’s instructions and been on my merry way. But I’m an engineer (Mechanical, hence why I’m not up on all this rectifier nonsense) and like to tinker so I searched around for info on how to make them function like stock simply for personal liking. As for others, maybe they like the instant on/off of LEDs or the intense pinpoint brightness but as with most vehicle mods, to each their own.
 

Jerry Bransford

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I agree, if one has stock fenders and light housings. For those changing over to tube fenders LEDs are generally the only option offered.
I'm running aftermarket PSC fenders (MCE in this older photo) and my turn signals are using the original incandescent bulbs and enclosures installed into JK enclosures.

CIMG4030~2.JPG
 

DougB

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I'm running aftermarket PSC fenders (MCE in this older photo) and my turn signals are using the original incandescent bulbs and enclosures installed into JK enclosures.

View attachment 189615
To each their own. I didn’t want to go that route since the GenRights come with a hole predrilled for the front 3/4” light. If I went grille mounted I would want to weld up the hole in the fenders. What did you put in the hole in the PSC fenders? Weld closed? Rubber plug? Nothing? Again, to each their own. Many don’t get the angry grille look but they sell enough for companies to profit and make more. 🤷🏻‍♂️
 

DougB

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The little turn signal hole is still in my PSC fenders, it doesn't bother me in the least. 😊

View attachment 189620

Well there ya go! I don’t get how that doesn’t bother you! LOL It would bug me. I would go to the length of welding it shut.

Now, if @jscherb came out with his JL griller overlay for the TJ, I might be tempted to go that route with in grille, CJ-esque lights and then would have to weld up that fender hole. To each their own. We all have our varying degrees of anal retentiveness. lol
 
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