Cargo light problem

Are you saying that a conventional incandescent bulb will still work in that socket, but the LED only comes on for a moment before shutting off? I'd probably suggest that there's something incorrect about the quality of the bulb you're attempting to use. Is it a bulb from a reputable company like Philips, GE or Sylvania? If not, I'd highly suggest starting there if you insist on wanting an LED bulb for your cargo area. If you can't verify the bulb being good, you're looking at a wild goose chase with a first assumption that it's something wrong with your vehicle.