System Outline
WARNING: This page is about a different car, the 2008 Lexus SC 430. However, it is still accessible from the selected car via links, so may be relevant.
The automatic light control system works when the light control SW is turned to AUTO. The automatic light control sensor detects the brightness around the vehicle. By this function, the system automatically turns the headlight on if the brightness is below the regular level and turns the headlight off when the surroundings become brighter than the regular level.