dwayne88.
Thank you for using the forum.
I have checked the Fault Codes in our 8700 product kowledgebase but could not find the specific Fault Code you have sited. I can see that 373 refers to tray 3 but there wasn't anything on 312-0.
http://www.support.xerox.com/support/colorqube-8700/support/enus.html
I would recommend that you call support and if they can't help you remotely then they will submit a request to have someone come onsite. 1-800-835-6100
My ColorQube 8700X keeps telling me that tray 3 is unavailable. Fault code 373-312-00. When I reset the machine it will work for anywhere between 2 hours and 2 days, then give me the same message again. I have removed and re-seated the tray and drawer, and it works when the machine is reset, so I don't think it's a connection issue, but it keeps happening over and over. Any ideas?