When the low beam is on, the external headlights work, when the high beam is on, all four. The two outer headlights use double-filament halogen dipped and high beams, while the inner headlights use single-filament halogen high beams. The electrical circuits of the headlights are protected by fuses, and the power to the lamps is supplied through a relay.
Attention! High beam headlight lenses must not be used in low beam headlights.