Model XV-N652S DVD player. When the "OPEN / CLOSE" button is pushed, the disc-tray opens, but it then "zaps" closed within a couple-of-seconds, without a manual-input from the remote-control. This applies whether the front-button on the unit or the button on the remote-control is used to "OPEN".

The most common cause for you problem is the tray is not extending all the way out. This can be because someon pushed
the tray in instead of of using the button. This causes the tray to jump a tooth. When it extends It now thinks it is jammed and the motor retracts the tray automatically. This is the cause 95 percent of the time. I've seen this problem more time than I can count. I've had my own electronics repair shop for over 25 years now and this problem has been around since they invented cd players. I have only seen this other cause about 10 times out of a couple hundred. Something is caught in the mechanism preventing it for extending fully and this is usually from customers with small children that put tiny object in the machine and they get hung up or a small particle gets jammed in the gear drive.
In both cases you simply open up the device and see what is actually happening. There is an easy but slightly risky quick fix is to give it a gentle yank as it is comming out to get it to jump a tooth back into place. You only try this on cheaper units as it has the potential to make it worse.
Once you have the case open you will see what is causing the problem in most cases. Look and make sure the limit switch is engaging when the tray is fully extended. You will have to look around for the limit switch as it is in different locations on the different versions of the drive. It is easy to locate because it is always in a piont where it can be strick by the tray and in some cases it is tripped by a cam on the gear box.
Watching what is going on in the mechanism will give you a wealth of information concerning you problem and I suggest you start there. If you find someone has jammed it in, simply get it back to the right position by either forcing it gently to jump a tooth in the right direction or dis assemble it a little further so you can make the adjustment with out forcing it. If there is something stuck in it, remove the obstruction. If the small plastic peice that trips the switch hes snapped off fabricate a reasonable facimally of the part. And as a last resort ultimately you can just buy a new or used drive and simply change it out.
This should be enough to get you well on your way. If you need more help, post your questions here and I will answer them for you. Hope this is enough to get you up and running.
George

Leave the unit off for 3 or 5 hours (plugged off from wall power)

and then switch it ON back.
this will get solved