Welcome to the new Xerox Support Communities. I am sorry to hear that you are having issues with your Phaser. Have you tried searching for these fault codes in the Phaser 8550 Online Support Knowledgebase?
The printer has been giving me error codes 13,266.44:23714 & 37,004.40:23778 right at startup it gets to about 90% then errors out. I have had a couple times where it prints the startup page and checker board page. When I called a local Xerox dealer they said it may be a power issue.
This unit is in my home office, so I moved it to another location in the house, same error.
Has anyone else had these same error codes and been able to resolve the issue?