Use a 680 Ohm, ½ watt resistor* to bypass the light sensor located on the passenger side dash in the speaker grille. If you're experiencing issues with your Mercedes automatic headlights, you're not alone. Modern Mercedes-Benz vehicles are equipped with advanced lighting systems designed for optimal visibility and safety, but even these sophisticated features can sometimes malfunction. It is super easy and can be done faster than reading this thread. If they do have that functionality, you probably have a light sensor installed on your vehicle.