Navigation screen does not close and drains battery. The screen reads...insert disk. As far as I know, the disk was never removed. When I hit the eject button nothing ejects. I inserted a random music cd, it accepts the cd. Does the system have a slot for more than one cd? If not this proves the original is missing. I currently must remove the fuse each time which also disconnects the radio. I believe it is not a gear problem because every once in awhile the screen goes down. I would appreciate very much if anyone has any information. Thank you.