A flashing lighting system, comprising: - a plurality of illuminators electrically connected to a power cable to be powered by it; - a plurality of power/monitoring/control modules (4A, 4B), each power/monitoring/control module (4A, 4B) associated with a respective illuminator and equipped with an electronic processing device configured to carry out monitoring and control operations and to process data based on a predetermined firmware recorded therein; - a central control unit configured to act on each power/monitoring/control module (4A, 4B) to send and receive encoded messages to and from it, said encoded messages including status control messages, said encoded messages being processed based on that firmware to determine the time for switching on and off the respective illuminator, to verify synchronization with switching on and off of other 15 illuminators, and to perform diagnostic operations; - at least a repeater device for receiving and repeating said encoded messages, the at least one repeater device being interposed between the central control unit and the power/monitoring/control modules (4A, 4B), the flashing lighting system being characterized in that: - the plurality of illuminators are LED illuminators, - the at least one repeater device is configured so that, during transmission of an encoded message, which is not a status control message, between said central control unit and one or more of the power/monitoring/control modules (4A, 4B), said repeater device receives said encoded message and repeats it to the respective one or more power/monitoring/control modules (4A, 4B) or to said central control unit, - the repeater device is configured, in the case the encoded message being a status control message, for retransmitting said status control message sent by said central control unit to a respective one of said power/monitoring/control modules (4A, 4B), if the power/monitoring/control 30 module (4A, 4B) does not reply within a first limit time (T out1) and for retransmitting said status control message sent by said power/monitoring/control module (4A, 4B) to said central control unit, if the central control unit does not reply within a second limit time (T out2). - a plurality of illuminators electrically connected to a power cable to be powered by it; - a plurality of power/monitoring/control modules (4A, 4B), each power/monitoring/control module (4A, 4B) associated with a respective illuminator and equipped with an electronic processing device configured to carry out monitoring and control operations and to process data based on a predetermined firmware recorded therein; - a central control unit configured to act on each power/monitoring/control module (4A, 4B) to send and receive encoded messages to and from it, said encoded messages including status control messages, said encoded messages being processed based on that firmware to determine the time for switching on and off the respective illuminator, to verify synchronization with switching on and off of other 15 illuminators, and to perform diagnostic operations; - at least a repeater device for receiving and repeating said encoded messages, the at least one repeater device being interposed between the central control unit and the power/monitoring/control modules (4A, 4B), the flashing lighting system being characterized in that: - the plurality of illuminators are LED illuminators, - the at least one repeater device is configured so that, during transmission of an encoded message, which is not a status control message, between said central control unit and one or more of the power/monitoring/control modules (4A, 4B), said repeater device receives said encoded message and repeats it to the respective one or more power/monitoring/control modules (4A, 4B) or to said central control unit, - the repeater device is configured, in the case the encoded message being a status control message, for retransmitting said status control message sent by said central control unit to a respective one of said power/monitoring/control modules (4A, 4B), if the power/monitoring/control 30 module (4A, 4B) does not reply within a first limit time (T out1) and for retransmitting said status control message sent by said power/monitoring/control module (4A, 4B) to said central control unit, if the central control unit does not reply within a second limit time (T out2).