Error 61 replace color imaging unit. Processor motor error... We have replaced this part.. Printed several pages and the error reappeared. Is there a sensor somewhere that can be cleaned? Is there a place to obtain an exploded drawing of this phaser 780.. I did not see one or overlooked on xerox site. This unit was donated to us by Kinko's. I am also wondering if the maintenance cost on this unit are goign to be a lot.. I can already tell the quality far exceeds my user community demands..??