ThatPreludeGuy's JDM's install page.
NOTE: This should only be done if your a) your willing to hack apart your JDM wiring harness b) you want your JDM's to go on when you want; i.e. not only with normal headlights, or c) you want to use the USDM switch but not the USDM wiring harness. Some of these directions were swiped from various sites so don't sue me for plagiarism.
Parts needed:
(1) JDM fog lights set
(2) USDM fog light switch (part# 08V31-S30-1M009)
(3) USDM fog light switch holder (08V31-S30-100R2)
(4) 5 pole SPDT relay - usually Bosch
(5) Extra lengths of 14 or 16 ga. wire
(6) Solderless connectors to attach wires to relay and one power lead to the battery as well as a few butt end connectors
(7) Bolts, lock nuts, and washers….. approx. 1 ¼" long to mount JDM's to the car (#10x24 Phillips screw 3/4--1 1/4" & lock nuts)
(8) Wire loom
Tools needed:
1. Very long slim Phillips head screwdriver
2. Wire strippers
3. Test light
4. Flathead screwdriver
5. Sandpaper
6. Razor knife of some sort
7. Radio code if your using the factory head unit
I started outside the car when installing them. To take out the front covers underneath the factory turn signals there's a spot on the inside of the cover that has a Phillips head screw in it to hold it in place. You need to back this screw out as far as possible, if I remember correctly it doesn't come all the way out of the cover. When you get those out you can run your front harness. There's already a lead in the car that goes from the driver side foot well to the driver side just to the right of the turn signal. The wire is orange and it has a round connector on it covered in clear plastic. With a little snooping you should be able to find it just fine. This lead is going to be connected in the car to the turn on for the relay we'll wire in next.
For the relay you'll want to find a convent location to mount the relay as well as being able to run wires to it. I chose a spot on the front radiator support that already had a hole in it to run a bolt through. The relay you purchase will have five pins and they'll be labeled.
86 Remote turn on from USDM switch.
85 Ground on car
30 +12v from the battery
87 Out to JDM fog lights.
Actually 85 and 86 are reversible, as well as (in this example) 30 and 87. You will not use 87a so simply slide a female crimp terminal over it to be safe.
The orange wire already in the car connects to the connector on the JDM fogs and runs over to the relay Pin# 86. Next you need to wire a constant wire from the battery to the relay Pin# 30, this helps bring the power right from the battery using a decent ga. Wire to power the JDM's instead of the cheap wire that's built into the car. From the relay you need to run two more wires, one wire to the rest of the JDM harness that connects to the lights themselves, that's connected to Pin #87 on the relay. The last pin, which is Pin # 85, is your ground; I ran this to the same spot I used for the ground from the fog lights. When you wire the ground to the car make sure you use some sandpaper and get a good clean metal surface to mount the grounds to. I used a test light to make sure the ground was good and when I was finished mounting both grounds to the spot I painted over it with a little bit of touch up paint to prevent rust in the future. Now some people have suggested adding an inline fuse of 10 amps from the relay to the JDM's but I never did and never had any problems so do it as you please. You need to use some of the solder less connectors to connect the power out to the rest of the JDM harness. I believe my JDM's came with a copper colored round connector to attach the ground to the car chassis, you shouldn't have to mess with that part of the harness at all. After all this stuff is sorted out and your wires are ran accordingly you can attach the harness to the JDMs and mount them. When you plug the harness to the JDM's you want to make sure that the orange wire of the plug on both the front lights, while looking at them head on face the passenger side of the car. Now I would wait until finished to bolt the JDM's in. Using long bolts and lock nuts makes for a huge PITA to get them out…for the thieves too though.
Inside the car:
There are 4 optional connectors in the fuse/relay panel on the driver's side. Their functions are as follows: 1.+12V When ignition is in the "ON" position. 2.+12V When dash lights are on (i.e. parking lights OR headlights are on). 3.+12V When ignition is in the "II" position. 5.+12V ALWAYS. (I'm sure about 2,5 and pretty sure about 1,3 but you might want to double check).
Inside the car -- I used the supplied JDM harness with the US switch and switch holder so I have all my switches when I'm done plus a dummy spot for anything I might want to add in the future. Like the Rockford Fosgate Bass Boost dial I'm using in there now. To remove the factory switch holder you simply need to pry at the sides and pop it out. I used a flathead screwdriver with the tip wrapped in a towel so I didn't damage the dash. On the plug that attaches to the JDM switch there is a little tab on both sides of the plug and one needs to be trimmed back to even to make it fit in the US switch. You can figure this out by trying first to plug in the harness into the switch; you'll then see which side tab needs to be trimmed back (that's where I used the razor knife).
From my JDM plug I have four wires...Black...goes to ground, Red/orange attaches to the Red/black with the silver dots at the fuse panel plug. Red/black goes to the orange wire in the car that runs outside to the relay. Red/black with silver donts was already attached to the fuse panel plug. To test at the switch the red/orange and red/black are 12v when the parking/head lights are on. The Red/black with silver spots is 12v to turn on the fogs.
This is a power in to your switch from the fuse panel and depending on where it's plugged in you'll get different options with the light. 1. Being on always, 2. On with ACC at ignition, 3. On whenever parking lights are on, i.e. if lights are on in any state then your JDM's will come on too. 4. I'm pretty sure is just a duplicate of one of the other spots. Hook your battery back up and test the lights, if everything works right then mount your fogs, double check all connections, tuck all wires, wire loom, etc…..