To all, This morning my right head light was out. I have seen that many have had this issue and when they turned it off and on the lamp worked. I will do that this evening. I am not surprised that it might be out. I have 130K on my 05 Prius, since purchasing new, so it would not be unusual for this to need replacing. I have replaced my Pacifica's Left lamp 3 times since owning and once under warranty. If I do need to replace the lamp, it is common that it is only the lamp? I have seen others need an ECU or ballast. If the Left lamp goes, it appears that the replacement is slightly more complicated. Is that true?
If your profile info is correct (05 with Package 2) you have halogen headlights and you can replace them easily yourself. Replace both lamps (left and right) at the same time and do NOT touch the new bulbs with your fingers. The oil in your skin will drastically reduce the bulb life.