Lighting or signaling headlight and system with at least one headlight

The headlight for a motor vehicle has a connector (71) for an electric power supply and a standard connector (72) used in a projector and connected to a multiplex bus. Controls are provided for the head or indicator lights and are connected to the feed and standard connectors to exchange commands and information for the state of the projector and bus. An internal bus (88) is connected between the controls and the lamps. Claims include a lighting system using the headlights.