Today, I noticed on a Passat 3c that when the long-range headlights are turned on, the left fog light also turns on and stays on as long as the long-range headlights are on.
I need to look into this further, perhaps someone has already encountered this before.
What could be the cause of the problem with the central control unit?
Maybe it's also because the right-front fog light is broken?
If I remember correctly, you can program the control unit for the lighting system so that both lights are on when using long-distance lights.
Turn the steering wheel to the right and check if the right-hand turn signal light then comes on.
My theory about the underlying theory:
Headlights are "on"
The turn signal lights are coded as fog lights.
Therefore, some people will honk their horn (i.e., use their horn as a warning signal) when using auxiliary lights (i.e., also known as a warning horn).