I have the tail lamp harness for my '02 fxd in my hand and need to know the functions of the wires so i can relocate the lights. I have the shop manual but either I'm missing something or the answers i need are in the electrical manual whih i don't have nor do i care to buy. There are 6 wires on this harness and then each of the turn sigs has 2 wires. Do any of you knowledgeable folk know which wires are what? Below are the colors for each as described in the manual:

tail lamp harness:
orange/white
brown
blue
red/yellow
violet
black

turn signals:
violet/brown
black

My next concern is that there are 6 wires in this harness and that my new after market tail light and the stock signals have 7 wires combined: 3 on the tail light (red, blue, black) and 4 on the signals (each have a black and a violet/brown as written above.) If anyone has the solution to that, please chime in. Thanks in advance. This is getting down to the last part of my winter mods and it's driving me nuts.

 

Go here to find some wiring diagrams:

***Dyna Models Wiring Diagram Links Index***

tail lamp harness:

• orange/white = running light HDI
• brown = right turn feed
• blue = running light domestic
• red/yellow = brake light
• violet = left turn feed
• black = ground

turn signals:

• violet/brown = turn signal feed
• black = ground

If the new tail light has a dual filament fitting my best guess for the wiring would be:

• black = ground
• red= stop lamp
• blue = running light

You could use a multi-meter to find out which wire is for ground....

 

Pardon my complete ignorance but what is the difference between the HDI and the domestic running light wires? And do you have any recommendations on the best way to ground out the lights? Also, i believe you posted a thread with pictures on disassembeling your turn signal housings. I need to drill holes in mine to re-route the wires and would appreciate a link to that. Thanks again for the help.

 

HDI = Harley Davidson International (Bikes sold outside the US)

Domestic = Harley's sold within the US.

So far I have not used the orange/white for anything since I have a domestic bike. If you do to just wire up your running light (blue on the new tail light) to the blue wire and the rest per FXD2003Rider's suggestions and you should be golden.

 

You ground out the lights with the black wire. The black wire is ground for all the lights in the rear.

And you don't need a multi-meter to check which light is which. you can buy a cheap light tester that has a body which holds a 12 volt light bulb in it and a sharp point on the end of the body. The other end of the body has a wire coming out of it that has an alligator clip on the end of it. Here is a link to one model on the web:
http://www.google.com/products/catal...=0CJYBEPMCMAc#

I am not endorsing any model of tester nor any place to buy them. You should be able to find these at any auto parts, hardware or general store that sells auto stuff for a very reasonable price and probably cheaper than the one in the link I gave your for an example.

As for testing:
Just clip the alligator clip to the black wire (your ground) or any well grounded part of your frame or engine (most wires on the tester are long enough for that), turn on your system, activate the function you are trying to find and then touch each of the wires in your harness. The first one you should look for is the running light. For that you just turn on your ignition switch, make sure no turn signals are turned on and the brake light is not activated. Touch each wire and the one that lights will be your running light. Now that you know what wire is your running light you won't get it confused with the brake light when you activate that switch and find which new wire lights. As far as the turn signal light they should be obvious since they will each flash. Just activate one turn signal at a time and find out which one is flashing.

 

Great write-up on how to use the test light to find out which wire from the main harness is for turn/stop/tail light!

As to the use of a multi meter: I was referring to the wires of the new tail light and not to use it to determine "which light is which".....

+1 on Robotech's answer!

Put a ring terminal on your new tail light's ground wire....




....and connect this ring terminal to one of the bolts inside your rear fender.


Here's the link:

https://www.hdforums.com/forum/7869922-post13.html

Anxious to know why you want to drill an additional hole in the housing?

 

I'm planning on attaching the signals under the swing arm by either bolting them to an L bracket hanging from the axle (tightened down against the swing arm by the axle nut) or by getting axle nut covers and drilling a hole in the bottom of those and putting a bolt through there as i have seen done by one of the members "Hickey". He used front turn signals for his rear which have one threaded hole and a seperate hole where the wires are routed. I included a picture below of how his were done. As you can see in the other picture of my turn signals, the wires come out of the threaded hole making it impossible to bolt to anything without a hollow bolt (these signals were part of light relocation bar needed to install hardbags; original picture included below). So my plan is to drill another hole in the signals, re-route the wires and seal the drilled hole with marine sealant to keep them water tight and then bolt the signals using a regular bolt in the threaded hole. If you are anyone has a better solution it's greatly appreciated. I don't have front turn signals to use for this application as hickey did.

 

ii love that look!!! run the wires thoughy our swing arm man!!!