Hello denethor,
Help can often be found in the Xerox Online Support Assistant here on Xerox.com. The knowledge base articles contain step by step instructions, many with color photos, to help resolve all sorts of problems. I have included a link below to the Phaser 7300 Knowledge Base for you to find the resolution to your problem.
http://www.support.xerox.com/support/phaser-7300/support-options/enus.html
Begin by clicking on the Start Troubleshooting link which will open a separate browser window. In the Support Knowledge Base window that just opened, type "end of life message" in the keyword search box on the right side of the window. Click on search result #1. Next, click on search result #2 (Resolving Replace (Item) and (Item) Near End of Life Messages). Follow the instructions in this solution to fix your error message.
Hopefully this helps to resolve your problem. If not, at the top of the knowledge base window you will find the 800 number for contacting the Xerox Customer Support Center (800-835-6100).
The things are supposed to last for 30K pages all of them failed before 15K pages. I replaced them all with new units direct from Xerox. now after a few hundred pages the Yellow says it's at end of life again.
I cleaned all the contacts, reseated it numerous times, seems to print just fine, but the error message persists on the front panel.