An automotive lighting system employing semiconductor light sources includes LED light sources (52) which are mounted to an edge of a heat pipe (44) such that emitted light from the LED light sources travels toward a reflector (32) at the back of the housing (24) of the system, where it is reflected and/or focused forward through the lens (40) of the system. The heat pipe is thermally connected to a heat sink (35) which extends outside of the housing and which operates to remove heat from the LED light sources. The thickness of the heat pipe is significantly less than the size of the reflector, so that only a small amount of reflected light from the LED light sources is obscured.