I got myself a 2003 mk4 Jetta Estate two months ago and here is my issue that I am trying to diagnose for some while. Basically, my front interior light is not working when opening any of the front doors. When turned to ON position, so basically turning the light on manually, it works perfectly, so the issue is somewhere else. The interior lights work perfectly when opening any of the rear doors or the boot. Also, when opened, the red lights in the front doors doorcards do not light up. I first thought that I have a bad door lock switch somewhere, yet the door locks are not acting funny at all, the car locks and unlocks as it's supposed to be. I want to mention that also, maybe linked to this problem, is that my windows do not roll up and down when holding the key in door in lock/unlock position.
Maybe one of you has an idea of what to look for.