A system for supplying power to at least one semiconductor element light source of a motor vehicle, the system comprising: means for controlling the power supply of said light source, configured to provide an electrical current to said light source, the intensity of the electrical current provided being a function of a BIN value of the source and the temperature of the source environment; an electronic circuit (120, 220, 320, 320, 420, 520) independent of said light source, comprising a first component (122, 222, 322, 322, 422, 522) having a measurable characteristic representative of said BIN value of the source, and a second component (124, 224, 324, 324, 424, 524) having a measurable characteristic as a function of the temperature of the light source environment, wherein the control means is arranged to determine said characteristics of the first and second component via a single electrically conductive wire (130, 230, 330, 430, 530) connecting the control means to the electronic circuit (120, 220, 320, 420, 520), characterized in that the electronic circuit (420, 520) comprises a parallel connection of a first branch including the first component (422, 522), and a second branch including the second component (424, 524), at least one of the branches including a selector circuit (421, 423, 525) connected in series and upstream of said first/second component, the selector circuit being configured to allow an electric current to pass through the electronic circuit (420, 520) selectively by said branch, as a function of a characteristic of the electrical current, and in that the control means comprises means for reading said characteristics of the first and second component, configured to selectively inject an electrical current having a predetermined characteristic into the electronic circuit. means for controlling the power supply of said light source, configured to provide an electrical current to said light source, the intensity of the electrical current provided being a function of a BIN value of the source and the temperature of the source environment; an electronic circuit (120, 220, 320, 320, 420, 520) independent of said light source, comprising a first component (122, 222, 322, 322, 422, 522) having a measurable characteristic representative of said BIN value of the source, and a second component (124, 224, 324, 324, 424, 524) having a measurable characteristic as a function of the temperature of the light source environment, wherein the control means is arranged to determine said characteristics of the first and second component via a single electrically conductive wire (130, 230, 330, 430, 530) connecting the control means to the electronic circuit (120, 220, 320, 420, 520), characterized in that the electronic circuit (420, 520) comprises a parallel connection of a first branch including the first component (422, 522), and a second branch including the second component (424, 524), at least one of the branches including a selector circuit (421, 423, 525) connected in series and upstream of said first/second component, the selector circuit being configured to allow an electric current to pass through the electronic circuit (420, 520) selectively by said branch, as a function of a characteristic of the electrical current, and in that the control means comprises means for reading said characteristics of the first and second component, configured to selectively inject an electrical current having a predetermined characteristic into the electronic circuit.