Fog Light wiring tips?

Greetings all, just a few quick questions.

Starting the long process of my serious MJ --> J10 restoration and need some pointers. I've seen front mounted fog lights not only on brush guards, but on the black plastic bumper on the front.

Case in point, 87 MJ with no brush guard :(

I figure I can drill out the wiring holes on the front and run the wiring to the battery though this empty space between the grille and radiator...

But my questions are:

1. Would I have to wire this differently (Read: More Carefully) than I already mentioned since the wires would be in close proximity to the very hot radiator?

2. Anybody do this wiring differently (or possibly easier) than what my idea is?

3. Also, how about running it through the firewall? Or is there possibly already hookups for factory fog lights buried somewhere in the dash? (mine came with none, but I heard that sometimes the setup is there) :dunno:

I pretty much ask the same question here is the thread to the answers I was given:

viewtopic.php?f=2&t=29833

hope that helps

The wiring is already there from a connector behind the dash to to the 10-pin connector on the front engine compartment bulkhead. You can use this existing wiring from a dash fog lamp switch to trigger a fog lamp relay mounted out on the left front bulkhead. This is how the factory did it. There also may or may not be the fog lamp wiring harness up front too if your truck came with factory lamps. If not, you'll have to wire that in from the relay to the fog lights.

The wiring is already there from a connector behind the dash to to the 10-pin connector on the front engine compartment bulkhead. You can use this existing wiring from a dash fog lamp switch to trigger a fog lamp relay mounted out on the left front bulkhead. This is how the factory did it. There also may or may not be the fog lamp wiring harness up front too if your truck came with factory lamps. If not, you'll have to wire that in from the relay to the fog lights.

Are either of those two plugs the ones I'm looking for?

Also, you happen to have a picture of the cluster of wires I should look for on the bulkhead? I ask this because I'm assuming the setup is different for a 2.5's engine compartment than a 4.0's.

Would it be possible to send me the diagram you refer to in this thread?

http://www.comancheclub.com/forums/viewtopic.php?f=2&t=29833

The 3-pin connector is the one used for factory fog lamps. You will have to add your own dash switch. PM me your email address and I'll send the schematic.

The easiest is to pull the front wiring harness (contains the relay) and switch from an XJ. The 10 pin connector is by the airbox. It's plug-n-play.

The 3-pin connector is the one used for factory fog lamps. You will have to add your own dash switch. PM me your email address and I'll send the schematic.

Thanks for the schematic Don :thumbsup: Pretty simple layout and setup honestly :eek:

The easiest is to pull the front wiring harness (contains the relay) and switch from an XJ. The 10 pin connector is by the airbox. It's plug-n-play.

Well, these pictures saved me a lot of time scrounging through the truck. Appreciate it :clapping: :cheers:

If you need to run wires across the front of the truck I have found the easist and safest is to put them in the existing cross body harness or wire tie them to that harness. This harness runs under the front of the radiator along the frame.

If you cannot get a front harness from an XJ (as shown by Fiatslug87) that had fog lights, the wire in the 10 pin connector (engine bay harness side connector) that you need is a light green one (on most of the harnesses I have seen). If you have an old harness you can remove a similar pin and install it in the front harness and run a new wire from there to the relay and fog lights.

We found the correct pin (in the 10 pin connector) by hooking up the switch on the dash and then using a multimeter to see when that pin was energized. Remember, the headlights have to be on, and the high beams off or the pin is never energized.

As Eagle said in a previous post, it is illegal to wire fog lamps to work alone or with the headlights off...and its just silly to wire them to work with the high beams on.

If you cannot get a front harness from an XJ (as shown by Fiatslug87) that had fog lights, the wire in the 10 pin connector (engine bay harness side connector) that you need is a light green one (on most of the harnesses I have seen).

On my 91 the fog lamp switched output was pin #10 of the 10 pin connector, a BRN/WHT wire. It's best to ohm it out to be sure and wire colors changed changed a lot throughout the years.

I wish I had those pics when I was trying to to my lights... I was kinda lost when it came to where the 10 pen connector was.. :shake:

If you cannot get a front harness from an XJ (as shown by Fiatslug87) that had fog lights, the wire in the 10 pin connector (engine bay harness side connector) that you need is a light green one (on most of the harnesses I have seen).

 

On my 91 the fog lamp switched output was pin #10 of the 10 pin connector, a BRN/WHT wire. It's best to ohm it out to be sure and wire colors changed changed a lot throughout the years.

Don is correct - Ohm it out...I had only seen 89 and 88 harnesses.

Was looking at the front of the bumper while doing some rust removal today. Stumbled across these holes.

Picture is a little dark, but there's about 4x1/2 spacing between the 2 pairs of holes (give or take 1/4 in.) on each side of the front bumper.

Am I correct that THESE are where factory fog lights would have gone? If so, do these just pop out? (If you look at the very first picture I posted, it seems that one of the Brush guard holes(?) still has a cover on it, where as the other one doesn't)

Yes, those holes are where fog lights and probably the push bar attach. The caps just push out, but I have seen some chrome ones that have a nut holding them on. The newer year (??) bumpers only have one hole on each side. I personally like the lights in the outer holes.

which position on the lower dash is the factory switch in -- left/right of column -- pic maybe?

Its in the lift side

and sorry about the :hijack: but are this really driving lights i thought fog lights were yellow? :dunno:

Two factory fog switch options for the MJ, one with cargo light:

Two factory fog switch options for the MJ, one with cargo light:

 

Thanks for the diagram :cheers: I know there was another topic on here about pulling the empty spacing covers for MJ's with no lights, power tranny, cargo lights, etc. And that the only way to get them out was carefully cutting it out.

I'm going to be making a junkyard run soon, and wanted to know if I find an XJ or MJ with the fog light toggle button, can I remove the button and wiring from where it's housed? I'm assuming it's going to be set up like the cigarette lighter in that the front plate is unscrewable and the wiring connects into it from the back. Disconnect the wiring and you can take the whole thing off. Am I correct here?

thanks for the pics --- extactly where I had put it -- got lucky eh?