Tail light wiring harness replacement

BlackHawkTJ

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Joined
Jun 24, 2019
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53
Location
Florida
Rebuilding a 97 TJ, the OEM wiring harness for the tail lights is toast, it was dry rotted or chewed by rats at some point and no longer will work. What’s the best way to completely replace the harness? Not to experienced with wiring so is this something I should have a shop do. Thanks.
 
Rebuilding a 97 TJ, the OEM wiring harness for the tail lights is toast, it was dry rotted or chewed by rats at some point and no longer will work. What’s the best way to completely replace the harness? Not to experienced with wiring so is this something I should have a shop do. Thanks.
Which harness is busted? Left or right? Body side or taillight side?
You probably can buy used harnesses from Davey’s Jeeps for not too much.

You might also consider purchasing a 4 way trailer light connector for the TJ, which comes with new male and female harnesses that fit the left side light. Those would be easy to cut and splice in place of the old ones.

If you have a 4 way trailer connector already installed, you should be able to remove it and simply plug the two leftover harnesses together to bypass it. Then you don’t have to mess with replacing it.

You can also replace the whole tail lamp assembly. Quadratec makes a popular LED tail lamp assembly that looks almost OEM, except much brighter, and uses less power. (The kit comes with the LED flasher relay.) Other companies make flush mount or low profile lights that aren’t OEM style. Most kits have the light side harness already wired in, so they’re plug and play.
 
Which harness is busted? Left or right? Body side or taillight side?
You probably can buy used harnesses from Davey’s Jeeps for not too much.

You might also consider purchasing a 4 way trailer light connector for the TJ, which comes with new male and female harnesses that fit the left side light. Those would be easy to cut and splice in place of the old ones.

If you have a 4 way trailer connector already installed, you should be able to remove it and simply plug the two leftover harnesses together to bypass it. Then you don’t have to mess with replacing it.

You can also replace the whole tail lamp assembly. Quadratec makes a popular LED tail lamp assembly that looks almost OEM, except much brighter, and uses less power. (The kit comes with the LED flasher relay.) Other companies make flush mount or low profile lights that aren’t OEM style. Most kits have the light side harness already wired in, so they’re plug and play.
When I removed the tail light assembly, the wires just came out with it. I’m not sure how far back it goes. I’m new at this restoration thing it’s my first project. Lol. I can take a picture of everything if that would help
 
How far back are we talking? Just at the plugs? If I'm not mistaken, you'll have the same Delphi/Weatherpak plugs as the '91-'95 YJ (they changed over in '98?). Can get male and female pigtails here: https://www.delcity.net/store/Weather-Pack-Assembled-Pigtails/p_810525.h_810527
Not sure, the tail lights weren’t working so I tried new bulbs and that didn’t work so I went to remove the assembly and when I had it removed it felt like it wasn’t connected to anything, lightly pulled on it and it came out freely from both sides.
 
The tail light assemblies have a pigtail that’s maybe 10 inches long or so. If you keep pulling, eventually you’ll find a harness. Unless somebody hardwired them in for whatever reason.

Alternatively, reach up into the space behind the wheel well. If you feel around, you should be able to find the harnesses and disconnect them.

The wiring harnesses should look like the ones in this product photo (from Quadratec):
5F1B6452-7E02-48AB-B14C-B877CA5915D6.jpeg
 
The tail light assemblies have a pigtail that’s maybe 10 inches long or so. If you keep pulling, eventually you’ll find a harness. Unless somebody hardwired them in for whatever reason.

Alternatively, reach up into the space behind the wheel well. If you feel around, you should be able to find the harnesses and disconnect them.

The wiring harnesses should look like the ones in this product photo (from Quadratec):
View attachment 116937
When i was replacing the brake light housing assemblies on my 04 TJ, the driver side had the harness to connect, but the passenger side did not (it only had the wires) and the previous light assembly wasn't connected. What is the name of this harness? So that i can Purchase and connect the new Passenger brake light via the harness. See attached For the end of the pigtail on the new brake light assembly.

D1E62326-A0AD-4EB6-A752-3825F83DE433.jpeg


ECFD4965-FFFB-4F2A-B62C-829EFD83A708.jpeg


2236EDB1-8E17-4703-8E49-B3EE0F04C58D.jpeg


A37CA40B-432F-4376-AC9E-1A899C243FE7.jpeg


0ECB6AC0-3142-42F0-ACB7-0DAD06F7030B.jpeg
 
I don't know if it actually has any official name.

Two places you could get a new pigtail:
Order a used one from daveysjeeps.com

Alternatively, you may be able to buy a plug in trailer wiring kit and cut the matching pigtail off and use that.
https://www.quadratec.com/products/92015_8002_07.htm
Thanks! I finally got the harness now i just ned to confirm which color wires connect to each other.
The 3 tail light wires on my jeep passenger side colors are red, white and blue. The new tail light that i purchased comes with 3 different color wires - red, green and black. Which color wires connect to each other ?🙏
 
Hmm. I'm actually not sure on the answer to that. Here's how I would find out:

Look up the taillight wiring diagram in your year FSM:
https://wranglertjforum.com/threads...ice-manuals-fsm-technical-documentation.4618/
That will tell you which color does what on the body side.

The taillight assembly has three wires for three different functions. One for the running light, one for the signal/brake, and one for reverse. The ground path is supplied through the bolts that hold the taillight on.

You can find out which is which by grounding the taillight assembly and then putting 12 volts on each pin to see what lights up. Note that the taillight must be grounded somehow or it will not illuminate.
 
Hmm. I'm actually not sure on the answer to that. Here's how I would find out:

Look up the taillight wiring diagram in your year FSM:
https://wranglertjforum.com/threads...ice-manuals-fsm-technical-documentation.4618/
That will tell you which color does what on the body side.

The taillight assembly has three wires for three different functions. One for the running light, one for the signal/brake, and one for reverse. The ground path is supplied through the bolts that hold the taillight on.

You can find out which is which by grounding the taillight assembly and then putting 12 volts on each pin to see what lights up. Note that the taillight must be grounded somehow or it will not illuminate.
Thanks !!

After doing some digging. I found out that the color of the 3 wires should have been:
1. Purple/Black = Reverse/Backup light
2. Black/Yellow = Tail running light or Side marker light
3. Green/Red = Left Stop & Turn Signal
4. Brown/Red = Right Stop & Turn Signal
So i followed the blue, red and white wires up and found exactly the colors mentioned first. After finding this, wires were soldered and new taillight was installed in a few minutes. Hope this helps the someone else in the future. 🙏
 
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Hello, do you remember which of those went to which wire on the tail light assembly? I'm going through this process now. I understand what each wire is on the jeep side, i.e. what you posted above. but how do I know what to solder those to on the tail light pig tail?