I bought a new 2013 FJ Cruiser two months ago. I have put 5000 miles on it. Drove it earlier today to the store & back. Hours later, I went through the garage to dump the trashm and heard a buzzing sound. Turns out it was coming from the back of my new vehicle. I opened the back door, and put my ear to the mat. You could clearly hear it. It sounded like a fuel pump or something, or a rely going crazy. I got the keys, and started the FJ, shut it off, and it stopped? What is/was it? I do not believe it would have stopped without cycling the ignition.