That is exactly why.
The right side has everything the trailer needs except left turn/brake, so they just run the left turn/brake over to the right side so the trailer connection can all happen there.
Last edited:
Is it possible to use export spec taillights in US TJs without having to run new wires?
- Thread starter psrivats
- Start date
That is exactly why.
The right side has everything the trailer needs except left turn/brake, so they just run the left turn/brake over to the right side so the trailer connection can all happen there.
Perfect! Thanks macho. A PO used the 3M wire splice/taps into the wiring inside the body tub for a trailer connection, so it probably doesn't serve any function for me.
I'll probably de-pin the brown/red from the connector so I can connect a brake light wire in it's place, to more easily wire the export tail lights.
Not a bad idea. Just curious what is your plan under the dash, find the brake light wiring before it hits the multifunction switch and disconnect it from there? That way the ambers are stopped from lighting up with the brake pedal?
And then rather than lengthen those wires way out to the back of the tub, you could just cut/heat shrink those wires, and tap the two tail light brake portions into the third brake light so they receive a brake-only input. Granted you'd probably have to run LED bulbs that way so the three bulbs wouldn't overload the circuit.
I always wanted to do this, my only flaw with it is the no DOT compliant side markers, and I'd have to move the plate. Plate isn't such a big deal, no side markers bothers me a bit more.
My plan is to remove Pin/wire 1 from multifunction switch C1. This should remove the brake light functionality down the greed/red & brown/red wires that will be used for the amber turn indicators. For the brakes function, I intend to tap into the CHMSL white/tan wire at the tailgate contact, and run wires to the two vehicle harness connectors in the empty pin locations. That covers reverse lamps (white), turn lamps (amber), parking lamp (dim red), and brake (bright red).
As for DOT compliance, I've tossed around several ideas for this. Get a custom bracket made that would give me a place to mount a trailer clearance/marker light in a vertical orientation right up against the outside of the tail light housing, and some other sort of light below the housing to illuminate the license plate. Underneath the red side marker light I planned to put red DOT-2C reflector tape, for the reflex reflector function. The more I think about it though, the wonkier I think it might be.
If you look back at jscherb's earlier posts, he used the domestic housing with the side marker and license plate lamps and created baffles inside to get proper functionality. I'm thinking this might be the better route to go. Just this morning I ordered the set of export lights, and then a secondary set of domestic tail lights from Ebay. I'm thinking a small LED panel in the bottom should work for the license plate. I think I should be able to remove the fresnel lens inside the domestic housing and replace that with an LED board. If I look at plug and play LED tail lights, they only seem to have a couple LEDs for the side marker lighting. As far as overloading the circuit, the export wiring seems to all just be on 18g wiring from the brake switch back. I'm not too concerned, but would prefer to have LED bulbs swapped anyway.
I plan to document the process as I go and have spent tons of time planning already. I asked my mechanic, about this for inspection purposes, and he said they don't actually look at side markers/reflectors per the Missouri book. Ymmv. But I agree, per DOT safety requirements, a lack of side markers/reflectors could warrant being pulled over.
As for DOT compliance, I've tossed around several ideas for this. Get a custom bracket made that would give me a place to mount a trailer clearance/marker light in a vertical orientation right up against the outside of the tail light housing, and some other sort of light below the housing to illuminate the license plate. Underneath the red side marker light I planned to put red DOT-2C reflector tape, for the reflex reflector function. The more I think about it though, the wonkier I think it might be.
If you look back at jscherb's earlier posts, he used the domestic housing with the side marker and license plate lamps and created baffles inside to get proper functionality. I'm thinking this might be the better route to go. Just this morning I ordered the set of export lights, and then a secondary set of domestic tail lights from Ebay. I'm thinking a small LED panel in the bottom should work for the license plate. I think I should be able to remove the fresnel lens inside the domestic housing and replace that with an LED board. If I look at plug and play LED tail lights, they only seem to have a couple LEDs for the side marker lighting. As far as overloading the circuit, the export wiring seems to all just be on 18g wiring from the brake switch back. I'm not too concerned, but would prefer to have LED bulbs swapped anyway.
I plan to document the process as I go and have spent tons of time planning already. I asked my mechanic, about this for inspection purposes, and he said they don't actually look at side markers/reflectors per the Missouri book. Ymmv. But I agree, per DOT safety requirements, a lack of side markers/reflectors could warrant being pulled over.
Makes sense, that's exactly what I would do too. Disconnects old brake input from the new ambers and gives the new brake portion a way to only be brake powered.
Yeah I struggle on the same thing. What you could maybe do is do it like an old 76-81 CJ7, put a reflective side marker housing up in place right on the side of the tub with a small bulb inside it. It would be on the parking/running lamp circuit. I think that housing J0994021 (Crown) would just be a simple 1" hole saw and then drill two screw holes. Maybe worth looking into, and then you would just need to splice in the running lamp socket to running lamp and ground. Jscherb's posts make sense and are a good way to go for sure but sounds like a lot of tedious work cramming all that in there lol.
License plate I would probably just move although yeah a small white one fastened to the bottom of the housing should work fine.
Did the factory export wiring put all 3 brake bulbs on one single 18AWG wire? if so, I guess that's about 5A?
Yeah the side markers you can probably get away with, although it definitely bothers me from a correctness standpoint. What I have now (QT LEDs) are very good in every way except I wish they had an amber option. It's hard to convince myself to go through all the work just to get the separate amber signals. If I could think of a good way to do it, I'd jump on it. Somebody in the aftermarket needs to make an LED version of the euros with plate and side markers built in.
Last edited:
Just occurred to me, you will need to do something about your new separate turn signals/brakes if you ever want to tow. Since trailers share the brake/turn like Jeeps do, you splitting them up on the Jeep will require you to do something along the lines of a converter that operates the trailer lights properly based off of whatever you do (signal, brake, etc) in the Jeep.
That's a valid point, and I'll keep it in mind if I intend to tow anything. At this point in time, I don't own any trailers and have no intent to tow anything with this vehicle. Thanks.
As far was the 18g wire goes, diagram 8W-51-2, shows 18g wire from the brake switch to the rest of everything. The high filament on an 1157 is ≈24W. Two of those (for each brake light), plus a 921 bulb (≈18W) is 66W. 66W @ 12V = 5.5amps. A wiring chart I have shows 18g wire is good for 7 amps @ 12V up to 20' of length.
Here's what I'm leaning towards more and more. Finer details still to be worked out. I may try to / have to make my own metal grounding/mounting plate inside instead of tearing it out of the export bodies. It might make some of the baffles easier to fit in. I'm fortunate enough to have access to a pretty well equipped fabrication shop at work. I'm not allowed to use that equipment, but I'm friends with those who are.
As far was the 18g wire goes, diagram 8W-51-2, shows 18g wire from the brake switch to the rest of everything. The high filament on an 1157 is ≈24W. Two of those (for each brake light), plus a 921 bulb (≈18W) is 66W. 66W @ 12V = 5.5amps. A wiring chart I have shows 18g wire is good for 7 amps @ 12V up to 20' of length.
Here's what I'm leaning towards more and more. Finer details still to be worked out. I may try to / have to make my own metal grounding/mounting plate inside instead of tearing it out of the export bodies. It might make some of the baffles easier to fit in. I'm fortunate enough to have access to a pretty well equipped fabrication shop at work. I'm not allowed to use that equipment, but I'm friends with those who are.
I looked more into it and you would need a converter like I'll link below to make it work. No big deal to wire up, and as you said you don't plan to tow really so maybe hold off on it until later anyways. Worst case, wire it in and be good to go. It takes the inputs from the vehicle with separate signal/brakes (your Jeeps brake, left turn, right turn) and outputs them properly to the trailer. I'm sure they have been solving the problem of separate signals on older vehicles without computers to work with towing likely for decades, so I bet this is a reliable option if you do need it.
3-Wire Vehicle to 2-Wire Trailer Converter Box
I've seen 18AWG to max out at 5A in the past but if Jeep did it, I'm sure it's safe. And as you said you're going LEDs anyways so no concern at all.
I think your plan will work. One of the fabricators at work can likely make it all happen. If you get it working, for sure post it up. Especially with the LEDs in the sockets, I'd love to see videos of it all in action. I use the high visibility bulbs from VLEDS, they're quite bright and great color. I bet the amber signals and their red options would shine very well behind the colored Jeep lenses. If the results look good enough on yours, I just may do the same thing to mine. So far I have QT LEDs and am too lazy to do the work until I see the results from someone else first.
Outback
New Member
Guys... there has to be a separate signal for the brake lights on the US spec jeeps. I am doing this on my YJ eventually, just a head scratcher for you guys to reach this conclusion yourselves:
"How does the third brake light illuminate?" In my YJ, even with the hazzards on the third brake light doesnt illuminate, only when the pedal is pressed.
First time I saw this style of light was in the UK, apparently they also had additional lights on the fender and where the windshield meets the tub, I personally like that style but I think just having some of these brake lights would be cool enough. For the license plate lamp I would recommend a trailer style light.
*Part of the reason I would like to do this style is because I want to run LEDs, but not loose the classic look of the light housing, so this is the perfect option, I order 2x 1157 Red led, 2x1156 Amber and 2x1156 White. Done!
"How does the third brake light illuminate?" In my YJ, even with the hazzards on the third brake light doesnt illuminate, only when the pedal is pressed.
First time I saw this style of light was in the UK, apparently they also had additional lights on the fender and where the windshield meets the tub, I personally like that style but I think just having some of these brake lights would be cool enough. For the license plate lamp I would recommend a trailer style light.
*Part of the reason I would like to do this style is because I want to run LEDs, but not loose the classic look of the light housing, so this is the perfect option, I order 2x 1157 Red led, 2x1156 Amber and 2x1156 White. Done!
I can’t tell if you’re actually asking how this works for your own info, or if you already know how it works and are posing a question for others to ponder no figure out. So I’m going to answer.
The brake light switch has an input from the battery and two outputs. One output goes immediately to the third brake light. The other output runs to the multifunction/turn signal switch (turn signal switch in a YJ). The switch allows the brake light power to flow straight through and out to the lights when signal or hazards are not on. When you put the turn signal or hazards on, there is a mechanical device built into the switch that cuts the constant brake light power to whatever it needs to (one or both lamps) and blinks that lamp(s) instead.
Outback
New Member
So regardless of how you wire the lights, in the end the circuit must be seperated? I see, I thought it was seperate because on the YJ the third brake light doesnt flash at all during hazzards and it has its own wiring (grey and white).
But that makes sense, is that "multifunction switch" also what controls the switchback between the fender and flare marker light?
Yes. Since currently, your turn signal and brake bulbs per side are one and the same, you can’t just install the euro tail lights. You need to disable all brake input going to the multifunction switch so that with the euro lights, the amber turn signals never light up when you hit the brakes. Which then means, you have no brake output in the back (except for the existing third brake wiring of course), so you either need to splice your two main brake lights into the third brake light (since they now need brake-only input), or you need to run the wire you cut to the multi function switch and extend it out to the two brake lights if you don’t want to add onto the third brake wiring.
Nothing controls the way the fender and marker bulbs work, that’s just how they happen to operate due to the way they’re wired:
The front bulbs are dual filament bulbs that use 3 wires:
-parking lamp power (low brightness)
-turn signal power (high brightness)
-ground
The side marker bulbs are single filament bulbs that utilize two wires, normally power and ground. However, the two wires are spliced directly to two power wires. The side marker is hooked directly to the parking lamps power and turn signal power of the front lamp….
When you are driving during the day and do NOT have the lights on, and decide to use the turn signal, the side marker receives a power supply on the signal wire. The side marker bulb seeks ground through the other wire (parking lamp power wire), and runs through the front bulb’s low brightness filament to find ground through the front bulb socket. So, the bulb blinks with the front signal.
When you turn on the parking lights, the side marker gets a power source from the front bulb. The side marker bulb seeks ground through the other wire (turn signal), and runs through the front bulb’s bright filament to find ground through the front socket. So, the bulb is lit constantly with the front parking lamps.
When you have the parking lights on AND turn on the turn signal, things go backwards. The side marker bulb is already seeing a power supply on the parking lamp wire, and it’s seeking ground through the turn signal wire as mentioned above. When you turn on the turn signal, the side marker is now seeing power from both sides, which means it’s no longer grounded. So every time the turn signal lights up, the side marker dies, turn signal blinks off, side marker goes back on. So that is how it works and why they alternate when lights are on.
This side marker bulb setup is called “floating ground” because the ground ‘floats’ between being seeked through the parking lamp or the turn signal wire.
TheGanzman
TJ Enthusiast
In my 65 years of life experience, I've found that the BEST things in life take the FEWEST words to explain: Sex, Coffee, Pizza, Sleep...did I mention Sex? If it takes too many words to explain/convince someone, it's just not worth the effort!
Hey macho, I’m still working on these. They’ve been back burnered for a while but I’ve pretty much got everything figured out. The side marker light will be done via an LED circuit board that fits into the slot where the fresnel lens was previously for the incandescent bulb. The also functions as a baffle to keep the amber light shining through the red side marker. And the license plate light is another LED circuit board.
PWMJeep
Member
I have been wanting to build a set of these for years. I even emailed back and forth with Jeff about his but have never gotten around to doing it. Using the US housings is definitely the way to go. mofsharick, those are works of art. The inside metal brackets are lovely. I like the added Jeep grille cutouts. Very nice. I do have a question about the LED panels, did you purchase them or build them ?
Thanks, Patrick
Thanks, Patrick
Thank you for the kind words. I spent ton of time making paper iterations of the grounding plate. I'm fortunate enough to have access to some pretty amazing tools at work to get custom waterjet work.
I designed the circuit board on JLBPCB, and then ordered the component parts and soldered them on. I took ample measurements of the driver side tail light housing to ensure it would fit properly. I assumed the little cutout notch would be needed in the same place on the passenger side, however that was probably a 1/4" different, so I just cut a small notch out of the board where it was needed.
I still haven't quite gotten these fully installed, but I'm pretty sure I'm passed all of the R&D parts. Now it's just soldering/heat shrinking/fit and finish. The biggest remaining hurdle is access the passenger side wires behind the evap canister, to piggy back on the CHMSL brake wire.
Still need to cut out gaskets for in between the lens and housing. Did a first attempt and the laser rezeroed it's home location when the cut was paused, and screwed up attempt #1. Burning neoprene smells horrible while being cut with a laser.
Last edited:
PWMJeep
Member
Well, the grounding plates are quite amazing. Have a second set you'd care to sell?
