4 headlight mod with high beam halogen and xenon HID-mk5

Nov 27, 2016
4 headlight mod with high beam halogen and xenon HID-mk5

  • How to have both the inner high beam halogen and outer HID xenon on at the same time on Volkswagen Mk5 Jetta, Golf, GTI, GLI(top)

    difficulty: 1/5

    This page shows how to enable the four headlight mod: both high beam xenon and high beam halogen on at the same time. You must have OEM high-intensity discharge (HID) headlights for the headlight mod to work.(top)


    In the United States, the stock configuration with the OEM HID headlamps, the inner pair of H7 halogen bulbs only light up when you pull the turn signal stalk towards you to flash your headlights (flash-to-pass) when the headlights are off. It's designed this way because halogen bulbs can light up faster, and it was initially thought not to be good for the HID xenon bulb to flicker on/off. When the normal - dipped-beam HID headlights are on, the flash-to-pass just raises the low beam shield so that it becomes the high beam. When you switch to high beams, the shield stays up. When the normal dipped-beam headlights are on, the inner halogen bulbs are never used.

    This mod enables you to have both the outer high beam HID xenon (shutter raised) and the inner high beam (H7 halogen flash-to-pass) lights on at the same time when you switch the headlights to high beam. Before anyone says this is dangerous, this is how many models of cars are from the factory with DOT approval, and how European-spec Mk5s are set - and you shouldn't have high beams on with oncoming traffic anyway. It doesn't take a genius to know that having more headlights on will result in more light.

    While you could also have the foglights on with high beams, it's illegal to have more than four lights lit on the front of the car in the US. Disclaimer: do not do this modification if it's illegal where you live and drive. See the TOS Agreement for the full legal disclaimer.

    Note - if your HID headlights were retrofitted, you must do the optional trigger shutter wire from the headlights to the CECM for the headlight mod to work.

    Overview of modification procedure(top)

    This mod first requires your instrument cluster code to be changed from 'American' to 'Great Britain' - see below for details. It isn't possible to do the headlight mod with a North American coded cluster. The GB coding change also removes the door open chime, and changes temperature to C, calculated mpg to UK gallons, and 12 hour clock to 24 hour clock. These can all subsequently be adjusted back to US settings. See 1000q: MFD settings for more features. If your car doesn't have a highline cluster, I'm not sure if you have the MFD settings screens. It also removes the "accept" acknowledgement when you turn on the OEM VW MFD2 navigation system. See the MFD2 FAQ in this wiki for more info on the GPS system. As of 2010, the latest firmware update for the MFD2 GPS system is version 50.

    Parts required(top)

    Procedure have both H7 halogen and HID xenon high beams headlights on at the same time(top)

    Change the instrument cluster code to UK or GB (Great Britain). For more details, see 1000q: disable door chime.

    Go back to the main screen and click on '09-Cent. Elect.' as shown in the image below to enter the central electric control module CECM.

    Click on 'Coding - 07' (ignore the Adaptation box circled below, the screenshot is from another writeup). Then click on 'Long Coding helper'.

    Use the right arrow button to go to 'Byte 17' - and uncheck Bit 1 'Deactivation of Additional High Beam with Bi-Xenon' as shown in the below image. Again, your cluster must be coded to UK for it to work or else this change alone won't do anything.

    You could also uncheck the Bit 5 box marked 'Front Fog Lights deactivated with High Beam' - but having lights down low (ie, front fog lights) when you want to focus on longer distances is counter productive and may degrade night vision. Furthermore, in the United States, it's also illegal to have more than four lights illuminated at the front of the car.

    Close the Long Coding window and it'll automatically copy/paste your new code (the yellow code at the top) to the right place. Then click 'Do it!' to save your new modified coding, and exit the module.

    To finish, exit VCDS, remove your VCDS interface lead from your OBD port, shut down your laptop or tablet, and carry out a visual check to admire your latest modification.
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