What are these capped off wires? They appear to be factory.

I've worked on plenty of fleet vehicles. (2006+ Superdutys, Crown Vic Police Interceptors, etc) They look like they're factory.

I don't have the upfitter manual for the Ex. Where do they end up?

 

Other end is up under the dash inside, they are customer convenience wires for easy access through the firewall.

 

Additionally for conversion/upfitting ambulance, tow trucks, etc.

 

And down there with them inside is a "customer access wire" that is a 10amp IGN-on-only switched/fused circuit.

 

Are these four wires present on ALL Excursions, regardless of options package?

Or do they take one away if it had been ordered with fog lights?

 

Mine has all four w/ foglights

 

See, that's what I don't get about domestic vehicles.

Ford and Dodge save money by making a million different harnesses for their vehicles.
(I ran into the same issue with my Dodge while trying to add factory remote locks.)

Like for the Excursion, we'd have at least SIX different harnesses.
XLT with V8, V10, and Diesel
Limited with V8, V10, and Diesel

Now it moves up to NINE.
XLT with three engine choices
Limited WITH Fog Lights x3
Limited Without Fog Lights x3

You've gotta have different production lines for each harness, have logistics for keeping track of each one (Part numbers, making different diagrams, etc.)

But yet they add the convenience wiring that 90% of owners will probably not use.

In my wife's Mazda MPV, I looked behind the bumper and there were pigtails for the fog lights. Drop the fog lights in the bumper, connect them to the pigtails, remove the blank plate on the dash and the foglight switch connector is behind it, put a fuse and relay into the blank spots labeled for fog lights in the electrical box under the hood, and call it a day.

Even my old 1985 and 1986 RX-7s have the wiring in the doors for power windows, regardless of being equipped from the factory.

They stock ONE wiring harness regardless of options.



Well, at least I know which wiring I'll be using for my fog lights in the Excursion... I just hate having random relays hanging out in the engine bay and drilling holes in the dash for a toggle switch. It all looks out of place.

 

Back in the old days, people cost less so it was "easier" to just put wires there.

Now with automation and driving costs down, it's cost effective to not waste.
Plus, a number of "options" are now "dealer installed" (especially on imports) so having the wiring harness present allows the dealer to install the fog lights (For example) on a Nissan Titan vs. having to factory order and wait 4 months, for an import.
Plus, some options are now "SW" enable-able from the dealer (hence why so many "features" are controlled via menu-driven displays)

With regards to the 4 wires you asked about, it's ironically a case of the SD platform (upon which the Excursion is based) connects those wires into the upfitter switches (and also has other wires for PTO purposes), so putting the short wires through the firewall makes it "easier" for the factory and for folks that want to MOD their SD/Excursion.
I also think the EB/Limited have the same harness (since my EB has all the options available "standard" in the Limited)
The vacuum lines and wire harness for 4x4 is also present on the 2wd (the vacuum module is on the pass fender, with a dummy plug). The PCM needs to be programmed (I believe) to ENABLE the 4x4 and of course the transfer case/wiring needs to be installed along with the 4x4 front axle/suspension..

 

It's not really different harnesses with ford and dodge. They both work in layers. Th optional layers for the build are added during final assembly.

 

The MPV is a 2003. Not really old.

Wouldn't one have the same factory order problem on a Ford?

The software controlled options are a reason don't like newer vehicles.
I can work a soldering iron. I can read diagrams. I can turn a wrench.

I can not access closed computer systems. I can not decode proprietary communications protocols. I can not break encryption.

I intend on modding the Ex. I'm gonna need a WHOLE bunch more wires through the firewall. On my Dodge, I made a whole custom harness for gauges. Two wires each for a pyrometer and trans temp gauge, Three each for a fuel pressure and boost pressure gauges, four additional wires for controlling torque converter lockup and exhaust brake.

Isn't the EB the same as a Limited with different trim on the seats?

Woah.. See, that also goes against the cost savings principle of neglecting 20 ft of 14 gauge wire.


Hmmm... So maybe I could add the factory fog light harness.
That's good news.

 

A Ford dealer here offered a factory fog kit that was plug and play. Lights, switch and plug in wires.

My base 2010 Mazda 5 has a wiring harness that already has fuses for options not available in the US, power sliding doors. I can buy power heated mirrors and the wires, fuses, relays and plugs are all there, bolt and plug them in. I was told that it was so options could be easily added.