This manual has been issued by hp Inc., to provide the service technicians of this product with the information necessary for qualified persons to learn technical theory, maintenance, and repair of products. 628 pages Contents of this service manual Product Information Service approach Operational overview Printer maintenance Theory of operation Removal and replacement Troubleshooting Parts and diagrams Introduction This manual covers service topics for the following printers and their paper-handling optional accessories: HP Color LaserJet 8500 printer (base model) HP Color LaserJet 8500 N printer HP Color LaserJet 8500 DN printer HP Color LaserJet 8550 printer (base model) HP Color LaserJet 8550 N printer HP Color LaserJet 8550 DN printer HP Color LaserJet 8550 GN printer HP Color LaserJet 8550 MFPprint engine only