If anyone is interested in this I can do a full write up with pictures (or just edit this one), but essentially what I did was rewire the taillights so the bottom part (the part that is the turn signals and brake lights from the factory) was hooked to the third brake light and only brake lights now. And make the top part (originally just a tail/running light) do what the bottom part used to. My car has been like this for 6 months now and it hasn't blown the fuse for the third brake light with leaving the bulbs the standard filament type. As stated earlier, if anyone is interested in a full write up with pictures I'll do that.
Rewiring taillights to make more sense 04+
- Thread starter Tombo
- Start date
industrialfish
New member
Yeah it sounds pretty simple, but I'd like to see it done as well.
As all of you know by now this is what the 04+ taillights look like from the factory. Just a third brake light and the lower half of each taillight as a brake light/turn signal.
This is what this modification will make your taillights look like when completed. Still the third brake light only now both the top and bottom of the taillight are brake lights. Also, the top half of the taillights is now the turn signal function as well. Below are the steps you need to do as well as a list of materials needed.
1: short piece of stranded wire (16 gauge minimum) about 10-12' (can't remember exactly how much I used as it's been a while)
2: new or used taillight sockets with 3 wires instead of the factory 2 for the upper sockets
3: pigtail splices
4: butt splices
5: razor blade or other sharp knife
6: new bulbs (not really needed, but since you'll have the lights off you may as well)
7: about 30-40 minutes of your time and as always a bit of patience
OK, so now that that's out of the way, here's how you go about doing this. First step is removing the taillights and putting them on your work surface. Take the sockets out. Now take the new socket and compare it to the hole. You'll see it won't go in. You'll see the tab that needs to be modified so it will go in. Line it up, Mark it and cut off the offending area.
Your cut should resemble this. Now cut the yellow wire leading to the bottom socket with enough to work with on either side. Splice the yellow supply wire to the top socket yellow wire. Splice all the other wires accordingly. I cut one wire at a time on the old socket and spliced them one at a time so as not to mess up which wire did what.
You're finished splices should look like this. You'll notice the yellow wire leading to the top socket had to be extended a small bit. Now run your wire into the car through the rubber grommet for the taillight wiring. I don't think I had to cut a hole in it to do so, but you might have to to gain the necessary room for the new wire. Just make as small a hole as possible so you don't have to seal it later. Run the wire as neatly as possible so you don't see it when you're in your trunk unless you're looking for it. Now using a pigtail connector splice into the white wire in the harness that goes up to your trunk lid.
This harness. Make sure to splice into it before the plug so if need be trunk lid can be unplugged and removed properly/easily.
This white wire. Now repeat for the other side, except splice into the new wire for that side so you don't have to disturb the factory wire more than you need to. Hopefully the pictures work.
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Trann14
New member
My favorite mod I've done to my car. Just makes the car look more normal I feel.
I did mine a bit different, but same concept. Replaced sockets, just tapped into the third wire on the lower light.
Glad to see someone else finally do this and do a write up!
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I did mine a bit different, but same concept. Replaced sockets, just tapped into the third wire on the lower light.
Glad to see someone else finally do this and do a write up!
Sent from my iPhone using Tapatalk
HighOctaneRacing
New member
subbed
That was actually my original plan, but then I got this crazy idea and ran with it.
industrialfish
New member
I'll admit I've never seen my lights from behind nor noticed others. So our top light is nothing but a running light? And this makes the top light mirror the bottom light?
HighOctaneRacing
New member
Wondering if this would cause any issues if one decided to use LED bulbs with resistors.
Bronco Boy
Donating Users
Cool mod.
You should at least tape those crimps. Ideally, re-do them with shrink-tubing.
You should at least tape those crimps. Ideally, re-do them with shrink-tubing.
Trann14
New member
Ive had LED bulbs in my tails for a few years now, and with this mod there haven't been any issues.
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April Thompson
New member
I notched my tail housings to make the sockets fit (flat file, 1/4" shaved, 30 seconds each, no problem!), but otherwise had the same idea. Going to the next level though, to get fully independent indicators, will involve a 2-to-3 converter like you find in cars pulled by RVs; the combination signal (yellow wire #43 & dk. green wire #48 on the BCM C2 connector [on 04 at least; later cars might differ]) would splice into the converter's combination input, and the dedicated indicator output will pick back up with the yellow & green wires, and the dedicated brake feed can either go into the white brake feed (#30 on the same C2) or run new lines to the back, though I'd go with wiring through the 3rd brake, as that'll keep the system from being confused when the 4-ways are on! Would love to have amber turn signals (like my '89 GP), but even the bespoke tail light shops can't be ersed! Modify Spyder LEDs? One thing at a time...
WarStryker13
I break things.
resurrecting zombie thread, but if anyone has done this and has pics that work, I'd be very appreciative. 
Explicit_Spade
Perma-Banned! JK LOL
How much of a difference does this make in light output for the brake light and turn signal?
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WarStryker13
I break things.
I don't think it makes any difference in light output, I just think it makes more sense for the lights to be wired as brake on the bottom, and turn/tail/brake on the top.