An illumination system for a vehicular tailgate includes a tailgate bracket at the tailgate of the vehicle, an illumination device pivotally mounted at the tailgate bracket, and a weighted arm pivotally mounted at the tailgate bracket. The weighted arm has a pivot end and a weighted end opposite the pivot end. Pivotal movement of the weighted arm about the pivot end imparts pivotal movement of the illumination device. As the tailgate of the vehicle pivots between its raised position and its lowered position, the weighted arm imparts pivotal movement of the illumination device due to gravitational force at the weighted end of the weighted arm, such that light emitted by the illumination device illuminates the same ground region. The illumination device may project an icon and part of a light-transmitting element through which the emitted light passes may magnify the projected icon when the tailgate is in the lowered position.