Abstract: A unit for detection and signalizing of functional defects for public lighting. A unit characterized by the fact that it comprises, for the one part, an emitter module (21) with which each street lamp is equipped, preferably located in its post, at the level of the junction box, the emitter module being equipped with a detector for current consumption (23) using the alternative network of the supply line as the carrier of a detection signal, and for the other part, of a receiver module (22) located in the supply cabinet of the same zone, this receiver module managed by a microprocessor which transmits a defect signal to the control room over a telephone line. This invention is of interest for manufacturers and installers of materials, equipment and components for public lighting.