yet another goddamn fog light post...

ok, ive read every single thread on factory fog lights, and i still havent found the answer, so here goes:

first of all, i can find a good wiring diagram, chiltons sucks ass and sutozone has the same one on the website. so with that said, heres the deal.

while treasure hunting at my local yard, i snag some facotry fog lights, the harness behind the bumper and the switch for the interior.

i realize that the harness that is in my 98 (sans factory fogs) does not have the wires i need for the fogs. my first attempt was to use the new harness...but the plug behind the drivers side headlight is also missing the right stuff. so on and so forth, i realize by reading that there is nothing from the firewall forward for the fog lights.

THE ACTUAL QUESTION:
i want to use the factory switch
i have the factory lights installed
i have the plug in the panel for the stock switch
where do those 4 wires go...do they go to the pdc, or do they just end, lost in the abyss of wiring in the dash?
im trying to just use the stock switch, i dont care about having them wired into the headlights

can i use any of these four wires, or am i better off using and aftermarket relay and running new wires?

if the latter of the two, should i just cut off the connector behind the panel and deadend the factory wires for my own?

any ideas?

a wiring diagram would be nice too if anyone has it

thanks in advance

well, im not exactly one to reuse junkyard wiring. there are too many gremlins running rampent in those things.

using the factory switch and your own fresh wiring and relay sounds like the best idea to me. not to mention you would then have the ability to run with brights and fogs on at the same time (usefull for night vehicle recovery etc) where as most factory setups wont let you.

I'm pretty shure the factory wiring from the switch goes to the PDC, but IIRC it ends there. There are no termanals for the relays that are used for the factory set up. In my FSM for a 2000 (98 should be wired the same, but the wire colors may be different) the Violet wire comes from Fog relay #one in the PDC (this controls the light power, on off with the high beams, and would be a normaly closed type relay) you will need to find, and give this wire power when the parking lights are on (and if you want to be legal disrupt when the high beams are on). The light brown wire is the switched output from the switch that goes to Fog light ralay #two (would be a regular normaly open type). My FSM also indcates this wire changes to Pink before ot gets to the PDC. The black wire is the ground for the indacator lights inside the switch. The last wire (color isn't shown, but should be orange) is the nite time illumanation light power (dash light). If yo uPM me your e-mail addy I might be able to send you a PDF of the wiring diagram.


EDIT: Also FWIW you shouldn't use profanity in a thread title. A lot of people are on here during work hours, and it dosn't reflect good mannerism in the main fourm directory. It could get deleated.

The wiring diagrams in the factory service manuals get harder and harder to read as these things get more complex, so please be patient if even those who have the diagrams in front of us have trouble answering questions. A single component is distributed over many pages with cross references.

But anyway, according to my 99 FSM, the light blue wire from terminal 2 of the fog light switch itself is what feeds the positive current for the lights. The violet wire from terminal 3 goes to the PDC, where there are two relays, with most connections internal to the PDC, which control the switch. This is rather the reverse of what you'd expect. Basically, as I understand it, when conditions are correct, as determined by those relays, the switch works. When they are not, the switch is dead. Terminal 1 of the switch, orange wire, goes ultimately to fuse 6 in the junction block, and provides positive for the switch illumination. Terminal 4, black, is the ground for the switch illumination light and the "on" indicator light.

As I said, this situation is the reverse of how earlier versions of the XJ handled the fog lights. In those, the switch controlled a relay, and the power to the lights did not pass through the switch itself. In the later ones, it appears that the switch does indeed handle the whole current of the lights. I don't know what the current capability of that circuit is, but it appears to be only a 20 gauge wire. If you are planning to run very high wattage lights, or more than the normal two on the bumper, this suggests that you should probably interrupt that circuit and use a secondary relay, with the output of terminal 2 used to trigger the relay rather than to power the lights, and the power tapped into another battery source and fuse. It also means that you are likely to have a difficult time if you intend to alter the function of the fog lights, for example, to have them running with high beams on. You might do better then simply to interrupt the violet wire that goes to terminal 3, and connect it to a current source that is not controlled by the relays at all.

I am assuming, perhaps mistakenly, that the connections needed by the relays are all provided within the PDC. If this is not true, you can post back, and one of us can probably provide the pinouts, etc. for the PDC and relays. If Scooby is here when I'm not, try page 8W-50-10.

I doubt cursing God will help your situation..

i just got some new ones from walmart. they where $16. and i just spliced them into the wires that where already there. as long as you had 2 wires for each light. or just one. you can wire them in. remember the ground is the whole car.

Re: yet another darn fog light post...

thank you and i apologize for the curse, that was hours of reading and 2 am talking...hope i didnt affend anyone, if i did, again, im sorry

First off, ignore the factory wiring, you can't use it. There are no sockets in the PDC for the factory fog light relays. Just ignore that plug even though it does have power to operate the little LED in the factory switch. One of those wires in that plug is connected to the dash/parkiing light ckt. Now if you could find a factory PDC w/factory fogs you could swap PDC's, no idea how hard that is, I bought the add on kit from the dealer about 5 months after I got my 98 new. I wasted about 2 hours figuring out where that plug went and what was missing in the pdc so you don't need to reinvent the wheel...
There is a factory OEM add on kit available that has: New switch panel, new switch, two relays, cabling and correct connectors to plug and play the interior portion of the wiring.
What you can do is pin out the switch, find which pins will operate a relay, once those are identified you can then remotely operate a relay with it. If you get a Hella fog kit it comes with a fused relay. I hope you have a meter, $15 at radio shack will get you one good for this stuff..

i found a way!

heres what i did for a semi-factory installation. using a test light and a multimeter, i managed to get it to work.

first step was to use the factory plugs for the lights themselves, i added the wires to my stock headlight loom(for a clean install), i then cut out the fuseable link, and soldered the wires together. i extended the wires up near my battery, where i have two terminal blocks on the inner fender, you guessed it, one hot, one ground. i mounted an aftermarket relay to the inner fender near the terminal blocks. i connected all the wires under the hood to the relay, except the signal from switch wire.

i then moved to the inside of the truck. i want as close to factory install as possible, so heres how it goes. i took the plug out of the dummy socket in the back of the panel. i then cut the violet and light blue wires after the plug. i dead ended both of those wires on the dash side. i then spliced in a constant power wire(get that from anywhere) into the light blue wire on the plug. i then ran a yellow wire(totally coincidental that it is the same as jeepsareus kit) from the violet wire on the plug to the signal terminal on the relay.

the result is a switch that allow me to turn on factory fog lights, while retaining its ability to illuminate with the dash lights and function only when the headlights are on.

if anyone is interested ill make a wiring diagram and post it.

mbiker72 said:

if anyone is interested ill make a wiring diagram and post it.

Click to expand...

Feel free to do so...I'd look at it.
Thanks.
.
Oh, and congrats.

Re: yet another darn fog light post...

mbiker72 said:

thank you and i apologize for the curse, that was hours of reading and 2 am talking...hope i didnt affend anyone, if i did, again, im sorry

Click to expand...

Dosn't bother me any just tring to save you some possable headache. Sounds like you did what I was thinking, but didn't explain clearly.

ok, ive posted a few times, but ive never tried to post a picture...i have a paint file with the wiring diagram in it, how do i post it?