Factory Fog Light Switch

[WildMike]

Probably at the back where the factory lead is for the rear fog light.
Not directly off the switch*

Hope to see a picture of the exact position

Sponsored

 

[WuNgUn]

This is what I plan on using (and what I thought I had set!) for front/rear fog switch....
Anyone wanna confirm/compare?

 

[WuNgUn]

And hopefully the spread sheet is correct /up to date?
Using this one...

 

[‘21OBX]

Where will you connect the ditch lights to make them work with the rear fog switch?

To the white/blue wire that runs to the back of the car. This wire runs down the drivers side sill under all trim. I actually grabbed it under the sill trim in the rear drivers doorway. This gave me enough wire to run it out under the hood. It’s all in this thread a big thanks to @flip for the diagrams he posted. They are live and working. Now to find out where the drl/turn signal wires are as the lights I bought have amber as well. And I want to hook them to either the turn signals , drl or both as it’s not a real bright amber.

 

[‘21OBX]

Hope to see a picture of the exact position

Dang it your gonna make me go back out to the truck. Lol

Hope to see a picture of the exact position

I snipped it here then will take a page from ford book with hot glue and shrink wrap to seal it off. But dinner got in the way so that’s a tomorrow job.

 

[‘21OBX]

To the white/blue wire that runs to the back of the car. This wire runs down the drivers side sill under all trim. I actually grabbed it under the sill trim in the rear drivers doorway. This gave me enough wire to run it out under the hood. There it is just a trigger wire for a relay that then goes to the lights. It’s all in this thread a big thanks to @flip for the diagrams he posted. They are live and working. Now to find out where the drl/turn signal wires are as the lights I bought have amber as well. And I want to hook them to either the turn signals , drl or both as it’s not a real bright amber.

 

[drew707]

This is what I plan on using (and what I thought I had set!) for front/rear fog switch....
Anyone wanna confirm/compare?

I went through and verified your changes with notes of what specifically it's going to change and affect. I don't recommend changing defaults if they are already proved out to be correct, it adds to confusion later on if you make a list of planned changes and something wrong and you need to go backtracking. The BCM settings are fine, you went wrong in the IPC changes (explained below in that section)

BCM

726-38-02	**xx	xxxx	xx--	00	DRL with fogs (default setting)
726-39-01	**xx	xxxx	xx--	03	This setting enables fog lights in the BCM
726-39-01	xx**	xxxx	xx--	01	This is for LIN switch type (default setting)
726-39-01	xxxx	**xx	xx--	00	This enables function of the front fog lights
726-39-01	xxxx	xx**	xx--	01	This enables function of the rear fog lights
726-39-01	xxxx	xxxx	**--	00	This allows fogs with turn config (default setting)
726-39-02	xx**	xxxx	xx--	00	Fogs stay on with highbeams
726-39-02	xxxx	**xx	xx--	01	Fog setting resets to off each key cycle (00 is default)
726-39-02	xxxx	xxxx	**--	00	Rain sensor not present (default setting)
726-42-01	xxxx	0101	xx--	01	Fog/Cornering circuit (Alt. would be 04 Fog Only)
726-71-02	xxxx	xxxx	**--	01	Switching circuit for fog lights

IPC
This has been corrected. The changes in the spreadsheet are not at all correct and will only enable the rear fog light icon and will mess with other things.

720-01-02	xxxx	*x--	9	Enable front fog icon on dash
720-02-02	xxx*	xx--	Two Door = 6 Four Door =A	Adds rear fog icon to dash

 

[WuNgUn]

I went through and verified your changes with notes of what specifically it's going to change and affect. I don't recommend changing defaults if they are already proved out to be correct, it adds to confusion later on if you changed something wrong and need to go backtracking. The BCM settings are fine, you went wrong in the IPC changes (explained below in that section)

BCM

726-38-02	**xx	xxxx	xx--	00	DRL with fogs (default setting)
726-39-01	**xx	xxxx	xx--	03	This setting enables fog lights in the BCM
726-39-01	xx**	xxxx	xx--	01	This is for LIN switch type (default setting)
726-39-01	xxxx	**xx	xx--	00	This enables function of the front fog lights
726-39-01	xxxx	xx**	xx--	01	This enables function of the rear fog lights
726-39-01	xxxx	xxxx	**--	00	This allows fogs with turn config (default setting)
726-39-02	xx**	xxxx	xx--	00	Fogs stay on with highbeams
726-39-02	xxxx	**xx	xx--	01	Fog setting resets to off each key cycle (00 is default)
726-39-02	xxxx	xxxx	**--	00	Rain sensor not present (default setting)
726-42-01	xxxx	0101	xx--	01	Fog/Cornering circuit (Alt. would be 04 Fog Only)
726-71-02	xxxx	xxxx	**--	01	Switching circuit for fog lights

IPC
This has been corrected. The changes in the spreadsheet are not at all correct and will only enable the rear fog light icon and will mess with other things.

720-01-02	xxxx	*x--	9	Enable front fog icon on dash
720-02-02	xxx*	xx--	Two Door = 6 Four Door =A	Adds rear fog icon to dash

Wow... Thanks Drew.... Nice work!

Am I looking at the wrong doc for the changes? Or was it just not complete /up to date?
I'll go over everything again, to verify. Pretty sure the IPC changes I made are the culprit to my issues.
If it's not, I'll do a backup restore are reflash.
Thanks again for your help.

 

[drew707]

Wow... Thanks Drew.... Nice work!

Am I looking at the wrong doc for the changes? Or was it just not complete /up to date?
I'll go over everything again, to verify. Pretty sure the IPC changes I made are the culprit to my issues.
If it's not, I'll do a backup restore are reflash.
Thanks again for your help.

I normally cross check the 2021 F-150 spreadsheet since it’s the only model in existence that is on the same generation of programming (there’s small exceptions to that rule).

The BCM changes were mostly bulletproof so no worries there. I’m not sure who put those IPC changes in but they were way off. I’m not sure if you have a four door or two door but the rear fog change could have been a bug itself if you had a two door and followed the spreadsheet. The front fog change was wholly off and definitely also could have been why you had issues.

While I didn’t add the rear fogs, the rest of the changes verified/corrected in my post above are what I used on my own fog conversion so you should be good to go with them.


Edit: for extra credit on why the two door and four door thing matters for the rear fog: It has to do with the seating layout regarding seatbelts. There’s one less/more depending on your change and using the wrong one can cause an issue with the belt monitoring system.

 

[WuNgUn]

I normally cross check the 2021 F-150 spreadsheet since it’s the only model in existence that is on the same generation of programming (there’s small exceptions to that rule).

The BCM changes were mostly bulletproof so no worries there. I’m not sure who put those IPC changes in but they were way off. I’m not sure if you have a four door or two door but the rear fog change could have been a bug itself if you had a two door and followed the spreadsheet. The front fog change was wholly off and definitely also could have been why you had issues.

While I didn’t add the rear fogs, the rest of the changes verified/corrected in my post above are what I used on my own fog conversion so you should be good to go with them.


Edit: for extra credit on why the two door and four door thing matters for the rear fog: It has to do with the seating layout regarding seatbelts. There’s one less/more depending on your change and using the wrong one can cause an issue with the belt monitoring system.

Rear seat belt monitoring issue is what I have! And yes, I drive a 2 door...
I wonder what put out the lane centering display...?
Lane centering still works but nothing on the svreen tells me I even have it!

 

[Roll Sound]

Rear seat belt monitoring issue is what I have! And yes, I drive a 2 door...
I wonder what put out the lane centering display...?
Lane centering still works but nothing on the svreen tells me I even have it!

Did you push the button on the steering wheel off and on again?

 

[WuNgUn]

Did you push the button on the steering wheel off and on again?

Yup... And it indeed turns the function off and on...
It's just it doesn't display anything
Likely to do with maybe the same line as the seat belt in the IPC

 

[TX-Hans]

Yup... And it indeed turns the function off and on...
It's just it doesn't display anything
Likely to do with maybe the same line as the seat belt in the IPC

 

[WuNgUn]

After I fix this, I'll have to take a look and see why my global windows stopped working

 

[BigMeatsBronco]

I normally cross check the 2021 F-150 spreadsheet since it’s the only model in existence that is on the same generation of programming (there’s small exceptions to that rule).

The BCM changes were mostly bulletproof so no worries there. I’m not sure who put those IPC changes in but they were way off. I’m not sure if you have a four door or two door but the rear fog change could have been a bug itself if you had a two door and followed the spreadsheet. The front fog change was wholly off and definitely also could have been why you had issues.

While I didn’t add the rear fogs, the rest of the changes verified/corrected in my post above are what I used on my own fog conversion so you should be good to go with them.


Edit: for extra credit on why the two door and four door thing matters for the rear fog: It has to do with the seating layout regarding seatbelts. There’s one less/more depending on your change and using the wrong one can cause an issue with the belt monitoring system.

Well this is interesting as I'm trying to turn OFF the rear seat belts ...due to my U-14 conversion I no longer need rear seat belt switches or sensors and without those parts, the idiot light stays on. I do still want the restaints indicator light to be able to work on the front.

Wonder if the as built off a 2dr F-150 would have the correct number of seat belts?

Sponsored