The headrests do go all the way down. I had something similar to this happen to me, but on the steering wheel column. For me, the wheel would adjust manually, but when I got out the wheel would not move up. They did replace the motor and now it works fine. Your problem could be a faulty headrest motor, which would need to be replaced. Someone correct if I am wrong, but I think you can "reboot" your seats. Something like move the seat back and hold it for 10 seconds, and move it to the front and hold for 10 secs. Hope this helps, if not take it in.