I have no idea when or where it happened. It could be due to age and vibration. I just found it when walking by the bike as I was getting ready to go for a ride. I guess it's time to upgrade them to modern LED lights. Harbor Freight has those 6" oval LED trailer lights for $15 each. They will fit in the trunk by modifying it. I know it's heresy to some but it's an upgrade that adds safety at night with much brighter LED tail, turn, and brake lights. I'll need to enlarge each pair of light holes to 6-3/4" X 2-1/2" openings. I'm going to make an adapter with an outside diameter the same as the current holes that will fit a standard 2 1/2" hole saw. Cut the holes to the new size and then connect them with a jig saw. Then those LED lights will pop right in with the rubber grommet that comes with them. I want the brake and turn signal functionally I had with the original lights in addition to tail lights Craig originally intended them to be. They came with dual filament 1157 sockets but only the tail light filament was used with just a 2 wire pig tail that connected to the tail light circuit on the bike. I made a new connector on my bike and along with LED 1157 bulbs added brake and turn signal functionally. I really like that because those trunk lights can be seen above my Bushtec trailer when I'm pulling it in addition to the lights on the trailer.