How best to add foglights and other Leds to Headlights and auto high beams

[Hahn Solo]

My truck was pre wired for the fog lights. Just had to activate it with Forscan in the BCM and now have fogs. You can also make a change in forscan to have the fogs on with high beam or DRL. Just had to add wiring from the connector that was pre wired that is by the passenger headlight. One wire is (left) and one is (right). If your interested in that option i can be more specific with the wiring. As far as triggering the fogs to come on, I just set them to remember their last state. So its like hitting the fog light button. Or you could just add the headlight switch that has the fog light button. My truck also has that pre wired. So ill eventually just order a switch.

Hey Antho, I want to add the fog button like you did. I think I found C134, but I can’t find a wire diagram to confirm which wires are the fog light circuit. Can you give me more details on what you did at C134?

 

[Antho]

C134 pins 3 and 4. Mine ran from the BCM to C134 and there where no wires on the other side of C134. So i pinned 2 wires and installed on the side that was missing the wiring. I have pins and connectors so it was easy. C134 was located in between the passenger headlight and grille. You can get a hand down there. The connector is secured with a plastic "Christmas tree". Proceed at your own risk.

 

[Hahn Solo]

Thanks, I did find C134 next to the headlight and thought it might be the 2 brown and yellow/orange wires, just wanted to confirm with a drawing before I mess with it. Unfortunately I don’t have any Ford connector pins. I’ll see if I can find an OEM connector I can rob pins from at pick n pull while I’m looking for a headlight switch with the fog light button. If not I might just cut those 2 wires and put them in my own 2 pin Deutsch connector.

 

[Hahn Solo]

Thanks Antho, worked like a charm.

Before:


After:

 

[DINOZR]

Thanks Antho, worked like a charm.

Before:
View attachment 160169

After:
View attachment 160170

That is super clean. Nice work! So you added a switch, completed the factory harness that was terminated behind the headlight, and now you can control the fogs of your choice using the button you scraped off a boneyard F-150?

 

[Hahn Solo]

That is super clean. Nice work! So you added a switch, completed the factory harness that was terminated behind the headlight, and now you can control the fogs of your choice using the button you scraped off a boneyard F-150?

Yeah, I added the OEM fog light button and completed the existing wiring harness to use it. I have Diode Dynamics SAE yellow fog lights on this circuit. Now, instead of using an upfitter switch for these, I have them on the fog light button that automatically activates them when the auto headlights come on.

Basically this is pretty simple to do because most of the wiring is already there. Here’s more info on what I did to supplement what Antho already posted:

1) Buy the headlight switch with the fog light button. I used part# SW7421, it was $50 through Ford Parts. No modification needed, just unplug the old and plugin the new.

2) Forscan, I used it to do three things. Enable the fog lamps in the BCM, enable the Bambi mode so the fogs don’t cut off when I use the high beams, and told it to remember if they were set on or off with the headlights between ignition cycles.

3) Attach two wires to connector C134, I guess you have two options here. First, you can cut the 2 fog circuit wires off this connector and add your own plug/splice whatever. Your second option is to add 2 pins to the other side of it that are attached to your wiring for your fog lights. That’s why I went to a junkyard, I cut this connector out of a wrecked 2015 F150, and then took it apart and used the pins to fill the empty side of the connector on my Raptor.

Here’s where you’ll find C134 at the front of the truck. Look down this hole next to the passenger headlight:



This is the connector:


At the top, 3rd from left is Brown and 4th from left is Orange/Yellow. These are the positive leads from the BCM for the left and right fog lights, as seen in the diagram Antho posted. At the bottom of the photo above you’ll also see two white pegs on the opposite side of those wires. I opened the connector, removed these, and then added my wires with the pins from the junkyard harness. Now mine looks like this, new wires are blue:



That’s it. Whole job took a little over 2 hours including the 40 minute trip to the junkyard and the dealership. Those two wires go to the left and right side bumper light pockets as positive leads for my SAE fog lights. For the negative leads I used a terminal ring and grounded each side to an 8mm bolt near each fog bracket.

My personal opinion is I think this wiring should be good for 5 amps of LED lights on each side, or 10 amps total since it’s basically two independent circuits (left and right) that trigger off one switch. For what it’s worth this oem harness is used for halogen H10 bulbs at 45W each, and many people upgrade them to 9005 bulbs at 65W each, including me when I had a 2015 F150 XLT. If you want to run something more powerful that triggers off the fog light button, just use these wires to trigger relays.

 

[blwn]

You guys are lucky. I tried doing this last year and my 19 isn't wired to C134 from the BCM. I was going to use a F150 harness that came with fogs, but it wasn't worth it to me to try and pin it back to the BCM

 

[Hahn Solo]

Actually, it would still be pretty easy like this:

1) Buy and install the switch.

2) Use Forscan to activate the fogs

3) Add 2 wires to the BCM harness. Specialty Performance already sells the backlight wire that has a BCM pin and instructions on how to put it in the BCM connector. Just buy two of those pre-pinned wires and put them in the 2 slots for the fog lights instead. Maybe they’ll give a discount for 2 if you ask? Anyway, connect these up to any 2 of the pass through wires.

4) In the engine bay, from the pass through wires you made hot for the fog lights, just run some wire direct to your lights same as you would from the upfitter bundle.

No need to deal with C134 at all if you do it this way, that’s only to make use of existing wire if you have it.

 

[mkenchSVT]

Yeah, I added the OEM fog light button and completed the existing wiring harness to use it. I have Diode Dynamics SAE yellow fog lights on this circuit. Now, instead of using an upfitter switch for these, I have them on the fog light button that automatically activates them when the auto headlights come on.

Basically this is pretty simple to do because most of the wiring is already there. Here’s more info on what I did to supplement what Antho already posted:

1) Buy the headlight switch with the fog light button. I used part# SW7421, it was $50 through Ford Parts. No modification needed, just unplug the old and plugin the new.

2) Forscan, I used it to do three things. Enable the fog lamps in the BCM, enable the Bambi mode so the fogs don’t cut off when I use the high beams, and told it to remember if they were set on or off with the headlights between ignition cycles.

3) Attach two wires to connector C134, I guess you have two options here. First, you can cut the 2 fog circuit wires off this connector and add your own plug/splice whatever. Your second option is to add 2 pins to the other side of it that are attached to your wiring for your fog lights. That’s why I went to a junkyard, I cut this connector out of a wrecked 2015 F150, and then took it apart and used the pins to fill the empty side of the connector on my Raptor.

Here’s where you’ll find C134 at the front of the truck. Look down this hole next to the passenger headlight:

View attachment 160180

This is the connector:
View attachment 160181

At the top, 3rd from left is Brown and 4th from left is Orange/Yellow. These are the positive leads from the BCM for the left and right fog lights, as seen in the diagram Antho posted. At the bottom of the photo above you’ll also see two white pegs on the opposite side of those wires. I opened the connector, removed these, and then added my wires with the pins from the junkyard harness. Now mine looks like this, new wires are blue:

View attachment 160182

That’s it. Whole job took a little over 2 hours including the 40 minute trip to the junkyard and the dealership. Those two wires go to the left and right side bumper light pockets as positive leads for my SAE fog lights. For the negative leads I used a terminal ring and grounded each side to an 8mm bolt near each fog bracket.

My personal opinion is I think this wiring should be good for 5 amps of LED lights on each side, or 10 amps total since it’s basically two independent circuits (left and right) that trigger off one switch. For what it’s worth this oem harness is used for halogen H10 bulbs at 45W each, and many people upgrade them to 9005 bulbs at 65W each, including me when I had a 2015 F150 XLT. If you want to run something more powerful that triggers off the fog light button, just use these wires to trigger relays.

Could you provide Forscan coding changes please sir!

 

[Morgan]

For a ’19 802a with adaptive cruise and parking sensors, would this be the correct harness to add factory foglamp plugs?
JL3Z-15K867-B
(I’d prefer to have OEM harnesses where possible)
@Antho
@Hahn Solo