Sur Golf VI ça se fait sans VagCom
Sur Golf V (ce qui est ton cas), tu n'as pas le choix c'est par VagCOm.
J'ai trouvé ça pour un touareg. Reste à l'adapter pour une Golf V
Your Volkswagen dealer's service department has the ability to disable the Daytime Running Lights (DRLs), but it is unlikely that they will perform this service for you (it never hurts to ask).
Another way to disable the DRLs is to change a setting using a VAG-COM. Without going into too much detail, you can disable the DRLs as follows:
Address 09 (Elect. Ctrl)
Function 07 (Recode)
Subtract 1 from the existing coding.
Presto, no more DRLs.
Doing this will add a menu item to the convenience settings in the Touareg's MFI that will subsequently allow you to turn the DRLs on or off without the use of a VAG-COM.
It may be illegal to disable the DRLs, or to drive a Touareg with the DRLs disabled. You are encouraged to check your local laws and regulations.