A light source control device for a vehicle, comprising: three LED light sources (Hi, Lo, PL) connected in series; a supply section that is adapted to supply electricity to the three LED light sources (Hi, Lo, PL); the three LED light sources comprising a first LED light source (Lo) that is adapted to be illuminated by electricity supplied from the supply section, a second LED light source (Hi) that is connected in series with the first light LED source (Lo) and is illuminated by electricity supplied from the supply section; and a third LED light source that is connected in series with the first LED light source (Lo) and is illuminated by electricity supplied from the supply section; whereby the anode of the third LED light source is connected to the supply section and its cathode is connected to the anode of the first LED light source and the cathode of the first LED light source is connected to the anode of the second LED light source and the cathode of the second LED light source is connected to the supply section, the light source control device further comprising a daytime running light connected in parallel with the three LED light sources a change section (SW, SW1, SW2, SW3, SW4) that is adapted to change a supply path along which electricity is supplied from the supply section to the three LED light sources (Hi, Lo, PL); characterized by the following features: the change section (SW, SW1, SW2, SW3, SW4) includes a first switch (SW, SW4) of which one end is connected to between the first LED light source (Lo) and the second LED light source (Hi) and another end is connected to ground; a second switch provided between the supply section and an electricity supply path upstream side of the third LED light source; a third switch provided between the supply section and an electricity supply path upstream side of the first LED light source (Lo); and a fourth switch of which one end is connected to between the first LED light source (Lo) and the third LED light source and another end is connected to ground; and the light source control device further comprising a fifth switch of which one end is connected between the supply section and the second switch and another end is connected to the anode of the daytime running light; a fault detection circuit that is adapted to detect a fault in the supply path; and a control section which is adapted to control on the basis of fault detection results from said fault detection circuit the first, second, third, fourth, and fifth switch in a sequence prioritizing recovery of the first light source. three LED light sources (Hi, Lo, PL) connected in series; a supply section that is adapted to supply electricity to the three LED light sources (Hi, Lo, PL); the three LED light sources comprising a first LED light source (Lo) that is adapted to be illuminated by electricity supplied from the supply section, a second LED light source (Hi) that is connected in series with the first light LED source (Lo) and is illuminated by electricity supplied from the supply section; and a third LED light source that is connected in series with the first LED light source (Lo) and is illuminated by electricity supplied from the supply section; whereby the anode of the third LED light source is connected to the supply section and its cathode is connected to the anode of the first LED light source and the cathode of the first LED light source is connected to the anode of the second LED light source and the cathode of the second LED light source is connected to the supply section, the light source control device further comprising a daytime running light connected in parallel with the three LED light sources a change section (SW, SW1, SW2, SW3, SW4) that is adapted to change a supply path along which electricity is supplied from the supply section to the three LED light sources (Hi, Lo, PL); characterized by the following features: the change section (SW, SW1, SW2, SW3, SW4) includes a first switch (SW, SW4) of which one end is connected to between the first LED light source (Lo) and the second LED light source (Hi) and another end is connected to ground; a second switch provided between the supply section and an electricity supply path upstream side of the third LED light source; a third switch provided between the supply section and an electricity supply path upstream side of the first LED light source (Lo); and a fourth switch of which one end is connected to between the first LED light source (Lo) and the third LED light source and another end is connected to ground; and the light source control device further comprising a fifth switch of which one end is connected between the supply section and the second switch and another end is connected to the anode of the daytime running light; a fault detection circuit that is adapted to detect a fault in the supply path; and a control section which is adapted to control on the basis of fault detection results from said fault detection circuit the first, second, third, fourth, and fifth switch in a sequence prioritizing recovery of the first light source.