When you say that as soon as you connect it to the power the lights flash and it states "loading" is that without actually having a disc in the drive? in other words you didn't unpower it with a disc left in the tray. If there isn't a disc in the tray then it could indicate a fault in the logic circuitry, as loading should only appear when the laser is interrogating the disc, also the normal advice of resetting the logic circuit by unpowering the equipment "will" of course have already been carried out, so it doesnt look very promising for any non-bench repair.