I believe this is what you have. I've got 2 small wire harnesses that aren't plugged in. If you look close, one on the left is a 3 pin coming from the camera plugin and on the right, the 4 pin from the Y harness. Do these plug into anything?
I replaced the battery housing after a crash with my q500. In the process a couple of the wiring harnesses were unplugged on the main board including a Y harness. Any way I can get an illustration or something to show how these plug back in?