Footwell Lights Retrofit Troubleshooting

[Fraysa]

Hey everyone.
I’ve completed my first retrofit today and installed footwell lights.
The lights are 100% regardless if the door is open or not.
I tried to change the brightness of the lights through the MMI but the slider doesn’t seem to do anything.
Anyone knows why?
Tried every possible adaptation online.

EDIT: Thanks to o_ravi we found the coding that makes this work! Check this post in the thread.

 

[Dr.Ed]

Did you try to reset your MMI?

 

[Fraysa]

Did you try to reset your MMI?

Yes. This actually doesn’t have to do with the MMI. Is has to do with lichtfunktion B that I can’t figure out which value to put in to make it work with the MMI.

 

[o_a_ravi]

Where is your footwell light wired to ? Is it to terminal C72 on the BCM Module ?

 

[Fraysa]

Where is your footwell light wired to ? Is it to terminal C72 on the BCM Module ?

Yes.

LC72
Lichtfunktion A is “Footwell Lights”
Lichtfunktion B is “58xs dimmer”
Lichtfunktion C is “Interior Lights”

 

[o_a_ravi]

Okay, sounds like you may be using a variant of footwell light coding, I posted in another thread. This was an alternate coding method., since the original/factory coding for Footwell light did not work/support. Which also means the footwell lighting will not be controlled from MMI menu (eventhough you will see the options enabled).

What this method does is, LC72 pin for footwell light is tagged to 58xs (instrument panel backlighting) and Interior lights., so with headlights on, the footwell light will go ON., and brightness will be controlled from the dimmer knob next to your headlight rotor switch., this is from - Lichtfunktion B is “58xs dimmer”

2nd Function (Lichtfunktion C is “Interior Lights” ) - Will make the footwell lights go ON @ Full Brightness when the domelight switch is at Door Position and when any door is opened.

Double check your coding again, hope you are missing something.

 

[Fraysa]

Okay, sounds like you may be using a variant of footwell light coding, I posted in another thread. This was an alternate coding method., since the original/factory coding for Footwell light did not work/support. Which also means the footwell lighting will not be controlled from MMI menu (eventhough you will see the options enabled).

What this method does is, LC72 pin for footwell light is tagged to 58xs (instrument panel backlighting) and Interior lights., so with headlights on, the footwell light will go ON., and brightness will be controlled from the dimmer knob next to your headlight rotor switch., this is from - Lichtfunktion B is “58xs dimmer”

2nd Function (Lichtfunktion C is “Interior Lights” ) - Will make the footwell lights go ON @ Full Brightness when the domelight switch is at Door Position and when any door is opened.

Double check your coding again, hope you are missing something.

Thank you for the detailed reply.

You are correct. I assumed this is an alternative coding because the factory coding has Lichtfunktion B has not active, which didn't really make much sense to me.

With Lichtfunktion B set to '58xs dimmer', the footwell lights are on even with DRL's on, so I found that by using 'Headlight Links' (not sure about the name gotta double-check that) - they turn on only when the low beams are on, which makes more sense to me than "always".

It's a bummer that we can't get the factory coding to work. On my previous car (Audi A3) the factory coding worked flawlessly.

Also, I'm not sure what "Lichtfunktion A" does and why we set it to "Footwell Lights". It doesn't seem to affect anything in my tests so far.

 

[o_a_ravi]

Thank you for the detailed reply.

You are correct. I assumed this is an alternative coding because the factory coding has Lichtfunktion B has not active, which didn't really make much sense to me.

With Lichtfunktion B set to '58xs dimmer', the footwell lights are on even with DRL's on, so I found that by using 'Headlight Links' (not sure about the name gotta double-check that) - they turn on only when the low beams are on, which makes more sense to me than "always".

It's a bummer that we can't get the factory coding to work. On my previous car (Audi A3) the factory coding worked flawlessly.

Also, I'm not sure what "Lichtfunktion A" does and why we set it to "Footwell Lights". It doesn't seem to affect anything in my tests so far.

Yes, if it was all working as intended. then LightFunction A = Footwell Lights is just enough., i also verified the BCM Output test, turning on the Footwell Light test from VCDS makes the light respond. But when coded and enabled from MMI, it woudnt respond.

Setting it to other options Headlight Links, will work. But you wont be able to use the dimmer function (as you have it with 58Xs).

Other option would be to set the Dimmwert Function AB to 50% from 100., will dim the output for functions A and B., so with your head light ON, your footwell will be lit at 50% creating an ambient effect.
With Function C = Interior Lights, Dimmwert CD = 100 will make it ON @ 100% with doors opening.

 

[Fraysa]

Yes, if it was all working as intended. then LightFunction A = Footwell Lights is just enough., i also verified the BCM Output test, turning on the Footwell Light test from VCDS makes the light respond. But when coded and enabled from MMI, it woudnt respond.

Setting it to other options Headlight Links, will work. But you wont be able to use the dimmer function (as you have it with 58Xs).

Other option would be to set the Dimmwert Function AB to 50% from 100., will dim the output for functions A and B., so with your head light ON, your footwell will be lit at 50% creating an ambient effect.
With Function C = Interior Lights, Dimmwert CD = 100 will make it ON @ 100% with doors opening.

I set the Dimmwert Function AB to 30%, and I kept the Headlight Links because of two reasons:

1. This way the footwell lights won't turn on at sun light (my switch is set to 'Auto', and by using 58xs they will turn on at sun light because of the DRL).
2. The dimmer function is nice, but it requires me to also dim the other ambient lights in my interior and I only want to dim the footwells.

Have you done anything to figure out why the factory coding won't work? I'm sure we can get it to work as my car comes with High BCM and there's no way it would work on a factory car but not on non-factory cars.

 

[o_a_ravi]

I set the Dimmwert Function AB to 30%, and I kept the Headlight Links because of two reasons:

1. This way the footwell lights won't turn on at sun light (my switch is set to 'Auto', and by using 58xs they will turn on at sun light because of the DRL).
2. The dimmer function is nice, but it requires me to also dim the other ambient lights in my interior and I only want to dim the footwells.

Have you done anything to figure out why the factory coding won't work? I'm sure we can get it to work as my car comes with High BCM and there's no way it would work on a factory car but not on non-factory cars.

Yeah i did a lot of tries and research to make this work., even compared with multiple US and Non-US Golf variant models for the coding and adaptations., but no luck. I think we must me missing something small., but no luck.
This is only retrofit that did not work (partially worked) on this MQB model vehicle. Have performed tons of other retrofits and mods., and even the more complicated ones worked. I guess the only other option would be to swap the BCM or to upgrade the flash file. But that is too risky and has a dependency on a lot other things. So did not try it. Footwell lighting is not that important compared to other things the module controls. Especially considering the alternative coding, i can live with it.

 

[Fraysa]

Yeah i did a lot of tries and research to make this work., even compared with multiple US and Non-US Golf variant models for the coding and adaptations., but no luck. I think we must me missing something small., but no luck.
This is only retrofit that did not work (partially worked) on this MQB model vehicle. Have performed tons of other retrofits and mods., and even the more complicated ones worked. I guess the only other option would be to swap the BCM or to upgrade the flash file. But that is too risky and has a dependency on a lot other things. So did not try it. Footwell lighting is not that important compared to other things the module controls. Especially considering the alternative coding, i can live with it.

Thank you for the detailed explanation. It's a bummer that we can't get it to work - I'm 100% positive it has to do with an adaptation we're missing but if you researched this and didn't succeed I won't mess with it.

 

[2018gti]

@Fraysa I haven't done this retrofit personally but at one point I did the 10-color ambient light mod and I remember seeing values in at least one channel concerning the footwell lights. Those were Interior lighting and Int. Lighting 2nd generation. That may be something to look into. Which year is your Golf by the way?

 

[Fraysa]

@Fraysa I haven't done this retrofit personally but at one point I did the 10-color ambient light mod and I remember seeing values in at least one channel concerning the footwell lights. Those were Interior lighting and Int. Lighting 2nd generation. That may be something to look into. Which year is your Golf by the way?

Interesting. My golf is 2016 (MK7 PFL). This mod sounds nice. Do you have a thread so I can take a look at it or part numbers? Maybe even coding so I can even see the fototwell light mention?

 

[2018gti]

Sorry, had to go dig it up.. here it is: https://www.briskoda.net/forums/top...ound-lighting/?do=findComment&comment=5254366. They deleted it off the obdeleven forums, probably to make people buy the app instead!

Anyways, go down to where it says "It's obviously necessary to have done the rest of the color coding"

And you'll see all the instructions there to enable the ambient lighting for doors and footwells. I'm not sure if your Golf will support it or not, but there may be values in there related to the footwell lights and they are disabled in your car.

 

[Fraysa]

Sorry, had to go dig it up.. here it is: https://www.briskoda.net/forums/top...ound-lighting/?do=findComment&comment=5254366. They deleted it off the obdeleven forums, probably to make people buy the app instead!

Anyways, go down to where it says "It's obviously necessary to have done the rest of the color coding"

And you'll see all the instructions there to enable the ambient lighting for doors and footwells. I'm not sure if your Golf will support it or not, but there may be values in there related to the footwell lights and they are disabled in your car.

Did you just do the coding or did you retrofit the ambient lighting to your vehicle?