[N26Ghost]

Originally Posted by azwillnj

I took the headlight switch out of my stock US spec 328xi and modified it to add rear fog lights. The button hardware, the lighting circuit and the button are all in the switch assembly, there are just little plastic tabs that are preventing the button from moving. After modifying the button you just need to code 5 new values to tell the car what to do with the new button and everything will work perfectly.


The first step is to pull the left vent out of the car, basically you just grab it and pull it out.


Next remove the headlight panel, there are little clips that you have to pinch while pulling the panel out at the same time, there are no clips on the bottom, the panel will tip out from the top. The clips are circled in red.


Once you have the switch out pull the wires out of the back, there is no button or catch, just pull them out. Then you need to remove the back of the switch, there are 6 clips that you need to release while simultaneously pulling the back off. The clips are circled in red below.



After you have removed the back you have to pop the button out of the switch assembly. Do this by pinching the four clips circled in red below and pushing the button out of the front.


Now that you have the button out you need to cut the retaining tabs off and smooth everything out. The tabs are circled in the pictures below. I used a box cutter to cut most of the tab off, then used a small flathead screwdriver to smooth everything out. It doesn't look pretty, but it works, and no one will ever see it, so it doesn't matter.



Tabs cut off and everything smoothed out.





After you're all done modifying the button, push it back in the front of the switch, clip the back of the headlight assembly back on, plug the wires back in, put the panel back into the car, then put the vent back in.

Now you have to code the button to work, refer to this thread to learn how to code or find someone in your area to help you. The values you need to code are:

FEM_BODY / 3060 LCEMaster 1C / NSL_Verbaut = Verbaut

REM / 3063 LCELampMapping 2 / Mapping_Nebelschlussl_L_output = nsl_l
REM / 3063 LCELampMapping 2 / Mapping_Nebelschlussl_L_Function = nebelschlusslicht
REM / 3063 LCELampMapping 2 / Mapping_Nebelschlussl_R_output = nsl_l
REM / 3063 LCELampMapping 2 / Mapping_Nebelschlussl_R_Function = nebelschlusslicht

And that's it, you're done. Let me know if you need any help.

Disclaimer: I am not in any way shape or form responsible anything bad that happens to your car, do this at your own risk.

One tiny edit:

REM / 3063 LCELampMapping 2 / Mapping_Nebelschlussl_R_output = nsl_r

Thanks so much to the OP for the awesome post. Was able to get this mod done in about 15 minutes including the coding and restart.

[i2023u]

Thank you for the excellent instruction. I have 2014 328xi (f30 US) and after DIY and coding, still mine is not working. I do not see rear fog light icon on dashboard. Is my firmware too old ? I have still factory firmware.

[kassey22000]

Thanks so much for this post.
Just like another fan posted, I was able to remove the tabbed rear fog light switch plate without having to take the entire switch unit out. Just used a plastic putty knife to carefully ease out the switch plate from the bottom portion. It popped right out. Once I carefully carved down the "preventative tabs" as pictured in this post, I just pushed the switch cover back in and it that was it for the switch mechanics.

For coding, I used the terrific Bimmercode app and followed N26Ghost's code update and bam! it works great!

1. rear fog indicator on the instrument panel - OK
2. rear fog lamps on with engine and full lights switched on - OK

Confirmed for this 2019 F31 build so I hope it works for others as well.

We'll probably never know why this was deactivated in the US market, but I'm sure that this option (when used properly with low-visibility driving situations) could save lives.

Great post!

[JDTX]

Here's another write up on this, as with kassey22000 this author didn't remove the entire switch assembly (not mine but on my list to try next):
https://www.normalexception.net/BMW-...rear-foglight/

[chowser51]

Just did this on an ‘18 F33. Works. Thanks.

I just pried and wiggled the button out without taking the switch out.

I did the switch thing in my ‘06 using Lego pieces and parts of a pen. The cutting the tabs off was easier.

[John in VA]

Originally Posted by kassey22000

We'll probably never know why this was deactivated in the US market, but I'm sure that this option (when used properly with low-visibility driving situations) could save lives.

Probably due to some archaic NHTSA law, but do we need more people driving around with auxiliary lights on as a fashion statement vs. utility? In countries that are allowed to have & taught to use rear fog lights, the light is on the side of the driver = left rear for USA. You don't need both rear fogs on - it could confuse other drivers.

[learntocode]

REM -> Mapping_Nebelschlussl_L_output: nsl_l
REM -> Mapping_Nebelschlussl_R_output: nsl_r

FEM_BODY -> 3060 NSL_Verbaut: verbaut

Values above worked and now I have rear fog lights, non-LCI F30. I think best method to remove the button is by using a thin plastic pry tool and gently push it out as opposed to taking out the whole assembly.

[learntocode]

Originally Posted by i2023u

Thank you for the excellent instruction. I have 2014 328xi (f30 US) and after DIY and coding, still mine is not working. I do not see rear fog light icon on dashboard. Is my firmware too old ? I have still factory firmware.

What are you using to code? I've used ESys on my laptop and if you follow the OP's guide it should work.. did you modify and insert back the rear fog light button correctly?

[Gixfighter]

Hi,

I’m having some issues coding rear fog lights on a 2013 f31 328i. The car has current/ factory I-level, f020-13-03-50? So was never updated. It’s a Canadian car, came without rear fog lights and had lci tail light units fitted without fog lights when purchased. It was recently imported into the Netherlands and since fog lights are required by MOT, pre-lci euro tail light units were fitted and suitable light switch.
I could find the variables to code into the REM module, but not in the FEM module to say fog lights are ‘Verbaut’. I did however find the option under LCE_BEL_LIN_VAR to say the light switch also has the rear fog lights (BEL_FLC_NSW_NSL).
The rear fog light switch does nothing.
I used ISTA to activate the rear fog lights, and it works from the REM, but not from FEM. Both modules have the option to activate the rear fog lights, but only work from the REM. I’m assuming this should also work from FEM, and something is still missing in the FEM coding.
I’ve used e-sys 3.27.1 with 4.19.21 lite psdzdata which is the latest I think. Can this be a problem with the old I level of the car?

Thank you all for any help. Much appreciated !

[Onizukachan]

According to the cheat sheet, only thing in fem body is NSL Verbaut. Just did it a couple weeks ago in my Sept ‘14 build date F31.

[haagm58]

Excellent writeup, OP!

I was able to get the physical button to work, however when I attempted to code via BimmerCode I could not find all of the options listed in the first post. For those of you who successfully coded this with BimmerCode, which parameters did you change, exactly?

[Onizukachan]

It’s in two different modules, only the first is in fembody, check the cheat sheet for 2-6? Which are in a different module. R.E.M. I think.
If you don’t want to deal with eSYS, try BMWAi program. It’s eSYS without a launcher/token. I use it for most things that don’t require adding custom values.

[haagm58]

Originally Posted by Onizukachan

It's in two different modules, only the first is in fembody, check the cheat sheet for 2-6? Which are in a different module. R.E.M. I think.
If you don't want to deal with eSYS, try BMWAi program. It's eSYS without a launcher/token. I use it for most things that don't require adding custom values.

Thank you. If coding in two different modules, we have to save and code one module at a time, correct? That may be where I went wrong.

[Onizukachan]

Correct. Code the fem body first, save the changes, then move on to the other module.

[Chaos236]

Thank you!
I really want a rear fog!!
My Cayenne's are wicked and back tailgaters right up day or night!

[haagm58]

Originally Posted by Onizukachan

Correct. Code the fem body first, save the changes, then move on to the other module.

On the second attempt, I was able to get it to work! What threw me off is the second to last code step in the original post; the instructed option is not available in BimmerCode (see below), however choosing the first option (nsl_r) enabled the right rear fog.

[donavo]

does anyone know which codes would make the reverse lights double as fog lights?

[SD ///M4]

Originally Posted by donavo

does anyone know which codes would make the reverse lights double as fog lights?

You can't code the reverse lights to double as fog lights. Why would you want to do that? Do you understand that "rear fog lights" mean that an inner portion of the red tail lights light up brighter when you press the rear fog light, provided that you've modified the headlight switch. It's not so you can see better when you back up in the fog, its so people behind you can see you better in the fog, from a farther distance. All this does is enable a feature that is standard in most European countries and the UK, and possibly other countries.

The part of the tail light that lights up brighter is what BMW calls the "brake force display" and lights up brighter when the car uses its built-in accelerometer to sense a hard braking force. When the headlight switch is modified, and the car is coded properly, these inner tail lights serve a dual purpose as both the brake force display when braking and as a rear fog light when you press rear fog light switch.

You really need to read this entire thread.

[Poochie]

Originally Posted by donavo

does anyone know which codes would make the reverse lights double as fog lights?

Mapping_Nebelschlussl_L_Output: 0X1E
Mapping_Nebelschlussl_R_Output: 0X1F

[donavo]

Originally Posted by SD ///M4

You can't code the reverse lights to double as fog lights. Why would you want to do that? Do you understand that "rear fog lights" mean that an inner portion of the red tail lights light up brighter when you press the rear fog light, provided that you've modified the headlight switch. It's not so you can see better when you back up in the fog, its so people behind you can see you better in the fog, from a farther distance. All this does is enable a feature that is standard in most European countries and the UK, and possibly other countries.

The part of the tail light that lights up brighter is what BMW calls the "brake force display" and lights up brighter when the car uses its built-in accelerometer to sense a hard braking force. When the headlight switch is modified, and the car is coded properly, these inner tail lights serve a dual purpose as both the brake force display when braking and as a rear fog light when you press rear fog light switch.

You really need to read this entire thread.

dont worry about my reasons, i just asked if anyone knew which values were the reverse lights. im not trying to see better. i live in cali and the rear fog lights are useless even for people behind me. but a nice surprise for tailgaters? now thats worth it. so thanks for your wonderful insight and valuable opinion.

Originally Posted by Poochie

Mapping_Nebelschlussl_L_Function: 0X1E
Mapping_Nebelschlussl_R_Function: 0X1F

thank you that worked. watch out tailgaters and people at red lights that think i left my car in reverse lol

[sick_guy]

Has anyone found just the rear fog light button for sale online? I'm interested in doing this mod, but I would rather just buy the button instead of spending so much money on the whole control system.

[haagm58]

Originally Posted by sick_guy

Has anyone found just the rear fog light button for sale online? I'm interested in doing this mod, but I would rather just buy the button instead of spending so much money on the whole control system.

Negative. I have only seen the entire controller. I once saw a sticker for sale, if I find the link I'll send it to you. I went the super DIY route and wrote the signal on it with a paint pen...it's not perfect but it reminds me of the DIY experience when I see it.