Built-in Fog Light Switch (Front/Rear) Installed

[Aminorjourney]

So I took the plunge and picked up a switch for factory-style front/rear fogs. My ultimate goal is to implement front-fogs in the lower grille as some others have done, but have it tied to the light switch.

So far, it's just the switch install, and some FORsacn tweaks, giving me front fog IPC telltale and auto-cancel for front fogs for when I actually install them. I will need to wire up a custom loom between front fogs and BCM -the factory manual seems to suggest it should work if I run the appropriate wires. (and relays)

The rear fog light switch and tell-tale have been enabled in FORscan, but they're not toggling on the IPC like the Front fog. Interestingly, I had a play yesterday evening with FORscan and was able to track the switch registering as a rear fog switch push (momentary only, so it showed ON when pushed and off when released).

I was also able to send the IPC the correct CAN code via FORscan to turn the tell tale on and then off again, so if for some reason my plan of trying to get it working factory-style doesn't work, I can program something on the can bus to latch the rear fog and activate the tell tale, using an aftermarket relay if required.

It's late, and I'm tired, and it's been a week - but hey, have a video. Turns out the light control cluster is modular, and we can switch out our bed lighting switch to keep a factory look.

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[Truaz]

That’s cool!

 

[nate002]

Interesting, can’t wait for the next one!

 

[21st Century Truck]

So I took the plunge and picked up a switch for factory-style front/rear fogs. My ultimate goal is to implement front-fogs in the lower grille as some others have done, but have it tied to the light switch.

So far, it's just the switch install, and some FORsacn tweaks, giving me front fog IPC telltale and auto-cancel for front fogs for when I actually install them. I will need to wire up a custom loom between front fogs and BCM -the factory manual seems to suggest it should work if I run the appropriate wires. (and relays)

The rear fog light switch and tell-tale have been enabled in FORscan, but they're not toggling on the IPC like the Front fog. Interestingly, I had a play yesterday evening with FORscan and was able to track the switch registering as a rear fog switch push (momentary only, so it showed ON when pushed and off when released).

I was also able to send the IPC the correct CAN code via FORscan to turn the tell tale on and then off again, so if for some reason my plan of trying to get it working factory-style doesn't work, I can program something on the can bus to latch the rear fog and activate the tell tale, using an aftermarket relay if required.

It's late, and I'm tired, and it's been a week - but hey, have a video. Turns out the light control cluster is modular, and we can switch out our bed lighting switch to keep a factory look.

OP, thank You for this ongoing research. Having had a US-spec BMW, a Ford Fusion and a Ford Mach E with factory-installed or self-installed OEM rear fog lights, I thoroughly appreciate having them when it counts.

NOTE for Your sleuthing: when I had installed a Ford OEM rear fog light onto my US-spec Mach E, I discovered that FORScan only listed one needed software change for this function within the BCM, whereas the BCM in the Mach E actually needed two separate software line changes. A German non-Mach E Forum member who specializes in Ford software found this additional solution by comparing the US/North America spec and EU spec BCM schematics for the Mach E.

Additionally, when I replaced the US-spec Mach E light control button with the Euro-spec Mach E light control button, I found out that there was no need to run a new wire from the light control button to the BCM.

Here's my write-up from the Mach E Forum blog. Maybe it'll be helpful to You:

https://www.macheforum.com/site/thr...nish-a-rear-ender-accident.28707/#post-845377

Separately, on my last trip to Europe I found out from Euro Ford dealer technicians that, as the F150 Lightning is not homologated for EU approval, the Lightning tail lights do not have an option for an internal OEM rear fog light, unlike the Mach E which does have this rear fog light built into its reverse center light (as described in the URL just above).

 

[roddiaz1]

Thanks for tackling this project. When complete, this will help many folks out there.

 

[Aminorjourney]

Thanks all - I'm wondering if there's lessons to learn from our Bronco cousins. They do have the option to add rear fogs, and I'm wondering if the lack of tell-tale on the IPC for the Rear Fog is part of a code issue, or just because I don't have anything plugged into the right BCM circuit for this.

Given that the Rear Fogs use a PWM controlled circuit, I wonder if it's just seeing an open circuit and therefore not showing it. I did some more digging into the FORscan thread on this one - and I think it's going to be a while...

 

[DavidS]

With the headlights placed so low on the front of the Lightning, do fog lights really improve visibility?

 

[Aminorjourney]

With the headlights placed so low on the front of the Lightning, do fog lights really improve visibility?

Yes. Fog lights are designed (the SAE ones at least) to give a consistent, low spread of light that isn't blinding, but give you a better view of the road.

Most SAE lights I've seen are yellow (although many stock ones are white) and that can also improve visibility in thick fog. My experience with the Ford F150 Lighting main headlights is that they don't always do great in fog, and can sometimes get confused by reflections.

As for the rears? Personal preference. I would rather allow my truck to be seen further down the road in heavy fog than the regular lights allow - and here in the PNW we do get some really nasty fog.

 

[rdr854]

We lived in Belgium years ago (actually decades) and rear fog lamps were mandatory. We had a US spec Volvo 244 and my Dad had to add the rear fog lamp so that it would pass the Belgian inspection. Interestingly, this was not required in Germany when we were there (car bought in Germany as part of US forces before moving t9 Belgium 18 months later).

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