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Finding correct wiring harness/installing fog lamps


I just purchased an '07 Ford Explorer Sport Trac, and it came with newly added fog lights (but still original- just added on after the original manufacture). The wiring isn’t in place to get these up and running. Where can I get the wires needed, and how the heck do I correctly install them? The vehicle already has the switch on the dash which controls all the lights (the kind you pull out to activate the Fog Lights), it’s just not hooked up.

I’ve attached pics of the dash so you can see the switch I’m talking about, and the type of light I’ve got (in case there’s any question about the connector).

Thanks a million,

Well the pictures won’t upload, so here’s an imgur link for them…

If the lights are not factory installed, don’t assume the wiring will be in place…It MIGHT be there and it might not. The wiring pig-tails for the fog lights, if they exist, will be taped to the existing wiring harness feeding the other lights…Look for an unexplained bump in the harness which will be your missing connectors…You may need to install a fuse to power up the circuit…

Alright. The reason I assumed the wiring was in place is because the switch is installed in the dash, an option that isn’t available on models w/o fog lights.

Thanks for the heads up. As always, you’re a life saver.

The company that makes the dash-boards, an outside supplier perhaps located hundreds of miles from the assembly plant probably installs the switch in all the dashboards they make. Or at the assembly plant, the exact correct dashboard was not installed, a common error as long as the color was correct and it matched the trim level of the vehicle…QC inspectors are not going to flag a vehicle for that…

Definitely no pigtails attached to the existing harness. Is the wiring something I have to purchase at the dealership, or is there an outside manufacturer that has what I need? I’m hoping to stay under $50 to get these up and running.

Repair manuals often have electrical diagrams in them. You might look at a Haynes manual for your year Explorer. The schematic can give you the tie-in location to the existing harness or show you where it connects to the fuse box or other electrical hook-up. Check the public library if you don’t want to buy the book, although you should have a Haynes, Chilton’s, or other basic repair book. If all else fails, go to the parts counter at your Ford dealer and ask them. They should have an exploded diagram that shows everything.

Back in the day, this is how it would be done. From the “ON” lug on the ignition switch or the lead that feeds the cigar lighter, run a hot wire, through a fuse (10A.) to the fog light switch. From there to both fog lights. Use #14 wire. From the second wire on the lights (ground) run a ground wire, also #14, to a good metal ground or body ground point. The lights will now function from the dashboard switch. The tail lights will not operate from this switch unless you do some fancy wiring.

If the connectors aren’t there replacing the wiring harness isn’t practical ($300-$500).
You can make a harness from the fog lights to the battery junction block using foglight bulb connector pigtails but I question if the rest of the system is complete. I wonder why a non fog light vehicle came equipped with a fog light switch.

A easier solution would be to puchase an aftermarket fog light wiring kit, (wiring, relay and switch).

Did you run a Carfax on this vehicle? A lot can happen over a 5 year period…

Yep. The vehicle is a rebuilt title. Mechanically, it’s in excellent condition- it was deemed a total by insurance because the core mount was damaged along with the radiator, and then there was cosmetic damage on the front end. The frame, steering and suspension, engine, and drivetrain were all inspected and certified to be unaffected by the accident. The core, radiator, and air bags (as well as the other components affected) were removed and replaced at a Ford dealership.

I guess with your question you’re inferring that the wiring harness was replaced with the incorrect one at some point? It’s possible, I suppose.

Nevada- Thanks for the diagram. Definitely helpful- if my statement above about the harness being replaced with the incorrect one is true, then it would certainly answer your question about why the equipped vehicle has no connector…

When the airbags blew, the entire dash was probably replaced with the one with the fog light switch…Or the front clip was replaced with one that did not have fog lights…

Now you know why things just don’t ad up like they should…

I see why you’d say that. They only replaced the airbag assembly though. It’s all good. I’ll look for a pigtail to hook up the fog lights, and let you know how it goes. Thanks a million.