I recieve an error code c 31 00 in my system. what do i do?

There's so much information missing from this question, but assuming this is a DVD changer, it's a disc error. Either the disc is upside-down or backwards and can't be read, is too dirty/scratched or unsupported and can't be read, or the entire mechanism is jammed or malfunctioning. If there are discs in the tray and you can remove them all, remove them and see if the error goes away. If the tray will not open, either take the cover off and remove the discs, or bring it to a service center.

Can you help me
I just open all cover but the CD still can not work properly its just stuck.

Its tray have 5 slots

This is for Sony Home theater system. DAV-FX500. I encountered C 31-00 on the screen just recently. I unplug the device and opened it. There were at least seven screw on the back and 2 each on back corner. I removed all of them. After that, there were still 3 screws at each upper side of the device holding the steel cover plate in place. The most important screw is at the bottom located at the middle section of the control. I removed it too. After that, I carefully pry opened the steel cover because I might damaged some circuit panel near it. I found my jammed cd. I dragged the cd out thru the back cd compartment by pushing the two plastic clip on the side. It is spring powered so it is easy. I pry up the cd afterwards. I just keep on pushing back and forth all the plastic arms with spring at the top to loosen it. Then , I plug the device again and used all the cd one by one. I played cd and eject it in all cd compartment. When I saw that all cd are running right , I unplug the device , replaced the steel cover and put the home system again to each original position. Make sure that before you put your cd again , be sure that the display says. ... NO CD.... This will help you from having the same problem again. I think I saved at least 100 dlrs from doing this. I hope it will save you too. Thanks.

I had this problem for a DAV LFH1, it is a single slot CD/DVD player. I fixed by undoing a couple of screws, and poping the plastic top off. Then I pulled out the jammed CD. I then opened the CD player metal slot open a bit wider, with the top off, with my fingers and the stuck eject arm popped up with a bit of a wiggle. Problem solved works fine now. Good luck.