Factory Fog Light Switch

[TX-Hans]

Ok guys, I hava badlands squatch Lux so I have the wiring harness for front fogs I am assuming that is what this photo shows. I replaced my factory headlight switch to one that includes fog light button which entailed ordering one of the switches that is in stock without the puddle lights and taking the puddle light module from original and adding it to switch with fog light (as someone else her showed us could be done). Puddle lights are working with the new switch for what it is worth. Next I went in to forscan and changed the BdyCM and IPC as instructed here to activate switch which included changing Some people f the coding in the BdyCM as built configuration. I am getting the fog light indicator to show up on the display but I am not getting any power to the plug. Has Anyone else run in to this problem? I am in my shop with no access to a computer. I can check forscan when I get back home but thought I would ask for any other ideas first. You should know I have 0 experience with electrical wiring or forescan. I would not have even attempted to do the fog light switch/ forrscan changes if not for this forum. So thanks in advance for any help

Make sure you follow the following to a T. Toward the end is a paragraph with some very critical information regarding 726-42-01 for activating the harness circuit.

I've been trying to find time to tackle this for everyone and finally did. I hope this can serve as the base of a write up for everyone, I don't have much experience making write ups but I will try my best.


To enable and utilize the factory fog light harness these are the steps needed. You will need ForScan (obviously but had to clarify) and the headlight switch of your choice, mine specifically is the auto lamp one with spot light buttons and just the single fog light in the center of the dial (I forget the part number if anyone knows)

Connect to the vehicle and go into configurations --> BdyCM and open it.
You will want to find and change the following:

Front fog lamps - change this from "Disabled" to "Enabled".
Fog Lamp Switch - change this to "Enabled"
Using Front Fog With High Beam - This is an optional change but if you want to use fogs with high beams change it to "Allowed"

Write the settings made, you are finished with the BdyCM for now

Next you need to open the IPC which will turn on the fog light indicator in your gauge screen:

Front fog lamps - change this to "Enabled"

Write this setting and now we will go onto the As-Built change.

You will need to open BdyCM (As-Built Configuration). BACK UP THIS FILE in case anything goes wrong you can restore the original.

Locate the following line:

726-42-01-xxxx-xxxx-xxxx (My Badlands specifically was 726-42-01-0000-0000-0575)

You will need to change the second box to 0101. ForScan does autochecksum calculations so what I ended up with was 726-42-01-0000-0101-0577

Write this change


I originally started with just the first two parts but while the indicator would show up on the dash I was not getting power to the fog light harness in the bumper. I was curious and compared to a 2021 F-150 spreadsheet. This 726-42-01 is the control line for what the Left and Right fog light circuit actually does. There's a few options but the default setting is "not used". The setting I changed it to (01) is "Fog cornering" (I assume 04 for Fog Only will work too) but there is another one (05) which basically turns that circuit into an always on 12v. The switch does not turn it off and while I tested it with the vehicle on I forgot to check it with the vehicle keyed off though I assume it would be a key on only setting. I mention this just because it could be useful to somone here who may not be hooking up fog lights but might want a low amp, I believe the fuse is only 5 amps, source for other accessories.

For those curious here is the full list of options but I only tried the two I mentioned:

LF_Fog_Lamp_Ckt_Usage_Cfg: 00=Not Used 01=Fog Cornering 02=Fog DRL 03=Fog DRL Cornering 04=Fog Only 05=Power Supply



Also, I did not research or attempt anything relating to the Rear Fog Lamps. I know some people here are seeking that but unfortunately I didn't dive into that yet.

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[Vantcrst]

Make sure you follow the following to a T. Toward the end is a paragraph with some very critical information regarding 726-42-01 for activating the harness circuit.

Yes thank you for that. I did go in and change that when I originally made the changes in forscan. I also have a badlands so I just tried doing the exact same thing and like mentioned the auto counter changed on mine just like it did for him so I assumed it would work. But after doing that I still have no power at the plug. Maybe I will mess around with forscan again and try some of the other options. Nubi question here, at the plug I see a yellow and a brown wire but I don’t see either of those color wires coming out of the back of the fog light switch. I am assuming wiring from the fog light switch goes in to some sort of control module or fuse box then different color wires go out to the plug in the bumper? Is there another place along this path that I can test to see if I have a bad plug, blown fuse or a bad fog light switch? And I think I read here somewhere that the two wires at the plug were power to each of the fog lights. Again I don’t know squat about wiring so I am assuming I have to create a ground for this circuit because I have two hot leads coming from the plug and each light has a hot and a ground? Thanks again for the help.

 

[TX-Hans]

Yes thank you for that. I did go in and change that when I originally made the changes in forscan. I also have a badlands so I just tried doing the exact same thing and like mentioned the auto counter changed on mine just like it did for him so I assumed it would work. But after doing that I still have no power at the plug. Maybe I will mess around with forscan again and try some of the other options. Nubi question here, at the plug I see a yellow and a brown wire but I don’t see either of those color wires coming out of the back of the fog light switch. I am assuming wiring from the fog light switch goes in to some sort of control module or fuse box then different color wires go out to the plug in the bumper? Is there another place along this path that I can test to see if I have a bad plug, blown fuse or a bad fog light switch? And I think I read here somewhere that the two wires at the plug were power to each of the fog lights. Again I don’t know squat about wiring so I am assuming I have to create a ground for this circuit because I have two hot leads coming from the plug and each light has a hot and a ground? Thanks again for the help.

The fog wiring plug at the bumper had a positive lead and negative (ground) lead on that terminal plug. Per @drew707, the colors are as follows:

"Yellow with Orange stripe is the power for the right side light
Brown is the power for the left side light"

The negative (ground) wire is the other wire on each terminal plug. Are you using a multimeter to check for power at the factory fog terminals on the bumper, or are you plugging in a fog light to see if it has power? If the latter, what fog lights are you using, and how are you plugging them into that factory fog terminal at the bumper? Did you build a male connection terminal for the factory fog terminal? And if so, did you correctly wire up the + and - on it to match the female plug's + and - layout?

 

[Vantcrst]

Well since I don’t have any confidence in my abilities I tried using a multimeter, trailer light tester where you just ground it and then poke stuff . It is entirely possible I have power there but don’t know what I am doing. Using the multi meter wouldn’t I just put the meter on DC put the positive in to the plug and ground the other lead somewhere? I tried that, Tried put putting both leads in to the pug etc.

 

[Vantcrst]

The fog wiring plug at the bumper had a positive lead and negative (ground) lead on that terminal plug. Per @drew707, the colors are as follows:

"Yellow with Orange stripe is the power for the right side light
Brown is the power for the left side light"

The negative (ground) wire is the other wire on each terminal plug. Are you using a multimeter to check for power at the factory fog terminals on the bumper, or are you plugging in a fog light to see if it has power? If the latter, what fog lights are you using, and how are you plugging them into that factory fog terminal at the bumper? Did you build a male connection terminal for the factory fog terminal? And if so, did you correctly wire up the + and - on it to match the female plug's + and - layout?

Here is a close up of the plug, I don’t have the bronco here but I only see two wires in this photo I took yesterday. Does that make sense given your understanding of how this would work?

 

[El Bronco Blanco]

Following for future use.

 

[drew707]

Here is a close up of the plug, I don’t have the bronco here but I only see two wires in this photo I took yesterday. Does that make sense given your understanding of how this would work?

Black with green stripe is the ground wire. The positive is Yellow with orange. Regardless of which you probe with positive or negative leads on a multimeter you should be getting a voltage reading when the fog lights are turned on.

You may want to first confirm your ForScan settings have taken once more. If you haven’t already. There are no direct wires to the switch just the LIN cables that go to the BCM. The BCM has the output wires for the fogs. There isn’t a fuse for the fog lights either, they are controlled by the BCM via a field effect transistor (FET) that monitors power draw. Essentially an electrically resettable break

 

[Vantcrst]

Black with green stripe is the ground wire. The positive is Yellow with orange. Regardless of which you probe with positive or negative leads on a multimeter you should be getting a voltage reading when the fog lights are turned on.

You may want to first confirm your ForScan settings have taken once more. If you haven’t already. There are no direct wires to the switch just the LIN cables that go to the BCM. The BCM has the output wires for the fogs. There isn’t a fuse for the fog lights either, they are controlled by the BCM via a field effect transistor (FET) that monitors power draw. Essentially an electrically resettable break

Ok, i will stay after it. Thank you guys!!!

 

[WuNgUn]

Debating between this or an after-market, have you put 12v to it to see how bright it is?


When you say behind the tire, are you talking from underneath or from inside behind the plastic trim?

If you go this route, you'll need to cut a hole in your steel bumper.

 

[tdiddy]

Oh, right. C192 is just under the headlight…I’ve pretty much given up being able to use the factory switch…so, I forgot what to look for at C110. I’ve gotta go back to my notes.

Is this the infamous C192? It looks like you might be able to get to it from underneath. My BD is still stuck on Ice Mountain or I would look...

 

[drew707]

Is this the infamous C192? It looks like you might be able to get to it from underneath. My BD is still stuck on Ice Mountain or I would look...

Unfortunately not, that looks like C1021 for the headlight.


However! The one to the right of it is in fact C192 (almost positive) It's hard to lock in exactly the colors on that but it's the right connector style and size for C192 and in the location it should be.

 

[tdiddy]

Unfortunately not, that looks like C1021 for the headlight.


However! The one to the right of it is in fact C192 (almost positive) It's hard to lock in exactly the colors on that but it's the right connector style and size for C192 and in the location it should be.

Here is the original taken from @pandapaul bumper install thread. Shows all the connectors in that area.

 

[redone17]

So, you’re saying there’s a chance…

 

[pandapaul]

Here is the original taken from @pandapaul bumper install thread. Shows all the connectors in that area.

I don't know connector names like you guys do, but if I can be of any help in describing what I saw or didn't see while replacing the bumper and relocating the ACC I'd be happy to do so.

 

[zedster]

Ok I received my ML3Z-11654-DA. So, what is the easiest way to get the switch out of the Bronco? Also, to swap over the puddle light switch? There are tabs all over this thing.

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