Will not complete the load cycle. Will not pley a disc.

There is a hidden loading belt that will stretch over a period of time, if the opening cycle can not complete it will close automatically.

There is probably a loading belt that is slightly slipping when tray door opens can't quite complete the cycle so it closes the tray.

Hello
Check it with an MP3 disc and a viedo disc. Cehck both of them are reading well and OK. Check with new CDs. If these discs works on and the problem occurs only with DVD discs, check it with other DVD discs. Some writion formats may not recogonized by the set. If the problem occurs with all discs, just put in a lens cleaning disc into the player, and pley it at least three times. This disc can be bought from most of the electronic spare parts at your town. If after cleaning, the problem perists, the Laser Pickup Unit should be replaced with same type and number. If you are experienced to disassemble and reassemble the CD mechanism, you can do it by yourself at home. It is a skilled work. If you are not experienced, get this set repaired either by Sony Authorised Service Center or by any well experienced service techinican you know well. OK.

There is probably a loading belt that has become stretched and the tray is not completing the cycle, " meaning it is not opening all the way and ends up closing just as fast " this a tricky repair best suited for a professional.

Sounds like you have a pump issue, make sure it is not blocked or restricted :)

I suspect that your 6 cd changer is having the fault. The error indicates always a system malfunctioning. From our point of view we can probe into for a solution by the following guidelines.
first of all open the 6 Cd changer from the top. look within to find that the changer is jammed inside. If so slowly tapp while you switch on the power. if the jamm clears and the changer ejects, then open out all the cd's present in the changer for any damage due to heat. If this did not solve, clowing chek for foreign particles/dust that has blocked the loading drive.from completing the cycle so as to reset the mode. normally all errors show because of the processor not receiving the complete cycle signals. hence check for all the moving parts, the drives and the loading mechanism. check also for any linkage damge, any leadd specially flexible line wiring to the motors for an open circuit. Slowly turn the motor drive to intiate to confirm if the motor has failed. Altogether use a multimeter and check in all the sections described.
I hope this helps. Good day.

try to stand it up on it's side or lay it down.

Have you tried the info from this link?

usually in the menu you will see an option called "finalise" chose this option for every recorded dvd aftre you have finish recording and this will close the disc and make it capable of playing on other systems. Hope that this helps