To use fogs as DRL you must have foglights installed the OEM way and not using an aftermarket relay harness. If you don't have foglights and wish to install them, see 1000q: foglight install.
You must disable DRL for the parking light position of a Euro switch to work. Otherwise it'll just be the same as DRL. See 1000q: Euro switch installation for details and demo pictures.
DISCLAIMER: You take full responsibility for any consequences of disabling the DRL or government mandated lighting. Any and all modifications you do to your car or a third party's car are at your own risk and all consequences to you or any third party are your full responsibility. This may not be legal depending on local laws. Always comply with local, state, and national laws and regulations regarding auto lighting and safety. See the TOS Agreement for the full legal disclaimer.
1 ross tech VCDS cable and a computer
Plug the VCDS into the OBD2 port and start the software/turn the car key to
"on". Below are some screenshots. Click on
"Select" to get to the control modules.
Click on "Cent. Elect". This is the central electric control
Click on "coding". You'll see the top screen in the below picture.
Click on "long coding helper" in the screen below and you'll bring up the next screen in the below picture. When you check off the boxes the long coding helper changes the numbers for you. The long coding is #1, the long string of yellow numbers at the top.
If you see the checkbox for Copy/paste it into the previous screen where it says "new coding".
Click "Do it!" to enter the new code. If it's saved then it says
coding accepted. If it's not saved or invalid it will not say that the
coding has been accepted. Always write down your original code before
doing any modifications! Always take screenshots before changing the
Click the checked box which says "Daytime running lights (North America). It will automatically change the long string of yellow numbers at the top next to #1 and copy/paste it where it says "New coding" once you exit the long coding helper.
Click "Do it!" to enter the new code. It should be accepted. This will disable the DRL.
The option for "Daytime Running Lights (Scandinavia)" is all lights on. The Scandinavian DRL is the same as turning the headlight switch to "ON" except the headlights are at reduced power and the instrument gauges are not lit. Turning the headlight switch will only change the headlights to full power and turn on any interior lighting.
If you have a 2010 Jetta, you could also try this:
With the headlight switch off, move the turn signal stalk down (signal left). Then pull the stalk towards you to flash the lights. Cycle the key on and wait for the ding.
To reactivate the DRL, move the turn signal stalk up (signal right). Then pull the stalk towards you to flash the lights. Cycle the key on and wait for the ding.
If you have a 2010 Golf, see 1000q: mk6 DRL.
The number "14' is highlighted in yellow in the picture above. This is "byte 0". Press the down arrow on your keyboard until you get to byte 17 (the number 28 is highlighted in yellow). This is just my 21 byte control module, yours may be slightly different so don't copy the numbers you see here. The long coding helper will automatically change the numbers for your car/settings.
In any case,
get to the one that has the option for "Daytime Running Light via Fog
Lights". Click the checkbox to make the green check appear.
NOTE - to use the foglights as DRL you must have DRL active. The checkboxes for North American DRL and the box below for DRL via Fog
Lights must both be checked. The headlights will not be DRL anymore
though, the foglights will. (I have xenon headlights, if you don't have
xenon headlights ignore that box).
This will change the long string of yellow numbers at the top next to #1.
Copy/paste it into the first screen where it says "new coding".
Click "Do it!" to enter the new code. It should be
accepted. You now have foglights operating as daytime running lights (DRL).
You may see "Deactivation of Additional High Beam with Bi-Xenon" but it doesn't do anything if your instrument cluster is coded as USA. It's possible to enable this option so that you have high beam xenon and halogen at the same times, see 1000q: 4 headlight mod and 1000q: OEM HID retrofit for details. You must have OEM GTI headlights as true bixenon by installing the extra shutter trigger wire to the CECM and have the checkbox for "xenon headlights with shutter installed" checked. If you uncheck that box and uncheck the deactivation of high beam box, it'll have halogen high beams and xenon low beams on at the same time. It's not possible to have halogen and xenon high beams on at the same time since it will reject the coding unless you do the mod above.
Do you have more questions about retrofitting foglights on your Jetta or Golf? Please ask in the forums linked at the top.