The oil may not have been properly extracted from the fuser before you moved the printer. If oil is present in a printer that is being moved and tilted, the oil overflow sensor can become contaminated, which will cause the oil pump error you describe. When the fuser oil pump error occurs, servicing is required.
Before moving your Color LaserWriter 12/600 PS follow the extraction procedures found in Appendix E of the user's guide.
This information is also applicable to the Color LaserWriter 12/660 PS printer.
This article was published in the "Information Alley":
Volume II, Issue 5, Page 8