Wii ejects discs from the DVD Drive?

Every time a disc is put into the wii DVD Drive, the wii will eject the discs after a couple of seconds. There is nothing in the drive; i took the drive apart to see what is going on. I suspect that it is the dvd controller board but am trying to get any confirmation or direction I can to solve this issue. I have two that are currently doing the same thing so I am unable to swap parts.

Thank you .