Lighting control device for a vehicle lighting device

Lighting control device (10) for a vehicle lighting device, comprising: a current supply control means (12) for controlling the supply of a current to a semiconductor light source (32) having a plurality of light emitting semiconductor elements (32a-32d) includes; a current limiting time-adjusting device (30) for setting, on the power supply control means, a duration of a restriction of supply of the semiconductor light source current to a value smaller than a predetermined current; and determining means (20, 18) for comparing a forward voltage generated by the semiconductor light source during the specified time (Vf) with an abnormality determination value (V2) to determine whether an abnormality is due to a change of the forward voltage of the semiconductor light source occurs, or not, characterized in that the forward voltage (Vf) becomes smaller than the abnormality determination value (V2) wherein the abnormality determination value (V2) is equal to or smaller than the minimum value of a characteristic curve (D) to the forward voltage (Vf) of the plurality of light emitting semiconductor elements (32a-32d) is fixed, and the characteristic curve (D) is the lower of two characteristic curves (D, e) is the forward voltage within the range (Vf) ...