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2 bulb to 3 bulb


Snal

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I want to convert my tail lights from 2 bulb to 3 bulb. I've read and been told I need the pigtail harness as well as the multifunction switch. Is that all that's needed? I can't find an answer or anyone on this forum who has every done this or even attempted it. I feel like the best way to do it is to remove the pigtail all together and splice the tails into the third brake light and splice the signals into the front signals
 


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martin

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I think you're right. No need to change any parts, marker lights are good, brake lights connect into third brake light and turn signals need to be spliced into front turn signals.
 

Snal

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I think thats what I'll have to do it just seems so ghetto rigged when I'm trying to build something nice.
 

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I think the "proper" way to do it is to swap the wiring and the multifunction switch. However no reasons are popping into my mind why splicing into the front signals and your brake light wouldn't work unless this would create some issue when you go to use the hazards... I'm not sure though (I'm looking at the diagrams for my '94 and the front & rear turn lamp circuits appear to be separate, but the rear circuits go directly to dead contacts at the turn signal switch (when switch is engaged) like there's something missing elsewhere on the diagram, so I'm not sure exactly where the rear bulbs get their power from when the blinker is on, or if it's tied in with the front or ? :icon_confused: )
 

Snal

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I don't know either and I really dislike electrical. if I could find a diagram that is extremely simple, as in color matching and big pictures like a kids book haha, I could probably manage I just wish I could see it done first
 

martin

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It's not the wiring that's complicated, it's the multi function switch that's complicated. I was going to to try and explain how it works but half a page of hard to decipher gobbledegook would be no use to anyone. I have a diagram somewhere that shows the connections in various positions but it looks like the timer sequence diagrams for a washing machine, so that would be no help either, I also can't find it. Essentially, on the 2 wire circuit it disconects the brake light wire from the brake switch and connects it to the front turn wire.
 

Snal

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I'm thinking if I get a multifunction switch out of a 98 or 99 and the pigtails it might be a plug and play situation because they're the same generation but I dont know. I have an 01 and a 00 so I'm gonna swing by the jy next week and see if it works on my 00
 

martin

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You'll still be two wires short for the rear turns.
 

Snal

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What if I swap in the whole wiring harness from the cab back? the one that bolts in under the driver? will I still be short from the multifunction switch to the harness do you think?
 

martin

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I don't know, but I would guess you will be still short. I still think your original idea is by far the easiest.
 

Snal

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forget it. I'm gonna make it harder trying to swap it over so splicing it is. Gonna get my turns from the front, brakes from the third brake light and running lights from the license plate lights. That should do it and I'll post pics next year when it's all put together haha
 

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You should not need to do anything with the running lights, different circuit.
 

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Here I am almost a year later and I'm a few weeks from putting my truck together so I've been working on getting this bar wired into my truck. It's a 5 light bar from ruff stuff that holds 5 6" trailer lights. On each end I've got the turn signals. The two next to those are my running/brake lights and the center light is a clear lens blue led. I've soldered all of the grounds together, soldered the two running light wires together and two brake light wires together inside the bar so I've got 6 wires coming out of the bar and are plugged into a 6 pin trailer connector. I've ran the ground to the post next to the battery where everything in the truck is grounded so I know it's a solid connection. I spliced into both front turn signals and they work fine. I've spliced into the third brake light and that works fine, it lights up both led lights. I haven't connected the blue light yet because I will be running that to a new switch somewhere in the cab. My problem is with the running lights. I've soldered into the license plate lights and connected it to the trailer connection but I got nothing. I took the wire that works the turn signal out and touched it to each post in the 6 pin to make sure everything is still connected all the way through to the lights and nothing broke, and sure enough all of the led lights work. that narrows the problem down to the truck but what's confusing me is that I can plug the license plate light back in and it works fine so I tried connecting to the tail light running wire, the front running light wire and even the corner light running wire and none of them will light up my trailer lights but I can plug them back into the led lights I put in the running lights and they work fine. I have no more ideas to try to further troubleshoot.
 

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I haven't tackled my wiring yet so I've read through this to see what I can do...

I'm using a 92 Ranger box with 96 wiring harness...what I was looking for was a way to use the 2 bulb 92 lights (rear for now...think I've figured out the front but...) and...I was going to put the brake lights in the top, the signals where the backup should be...need to tint the lenses or find tinted bulbs...and then wire the reverse lights and set them up on the rear bumper (below, actually)...

But if this conversion works I might try to merge the brake/signal lights into one connection...
 


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