2009 Lexmark T650, T650n, T652n, T652dn, T654n, T654dn Printer Service & Repair Manual (P/N 12G9824)

This Lexmark service manual covers the T650, T650n, T652n, T652dn, T654n, and T654dn laser printers in the 4062-XXX family, including basic and fully configured machines. Publication P/N 12G9824 is the June 9, 2009 edition.

• Fault isolation: Error-code tables, cartridge and system messages, image-quality symptom tables, NVRAM mismatch service checks, and network troubleshooting.

• Printhead and fuser repair: Printhead removal, mechanical registration, electronic oscillating-printhead alignment, fuser assembly replacement, and fuser-solenoid adjustment.

• Media transport: Multipurpose feeder, pick arm, duplex, and high-capacity input tray service, including feed tests, sensor checks, and component removal.

• Control electronics: System card, LVPS, and HVPS removal procedures, supported by hardware tests for the operator panel, buttons, DRAM, and USB ports.

• Output options: StapleSmart Finisher, 5-bin mailbox, output expander, and high-capacity output stacker testing, with removal procedures for their sensors and mechanisms.

• RFID UHF option: Installation and removal, firmware and interface-card fitting, and tag read/write diagnostic tests for the T654 option.

• Maintenance and parts: Expected-life tables, maintenance-kit identification, charge roll and transfer roller replacement, and illustrated parts catalogs for field replaceable units.

Lexmark prepared this maintenance information for professional service personnel, with electrical servicing and printer diagnostic work as part of its scope.

Diagnostic Tests and Print-Quality Checks

The diagnostic tables address memory limits, cartridge region mismatches, complex print data errors, paper jams, and fuser faults. Quick Test pages, base sensor tests, hardware test menus, and event logs support fault isolation at the component level.

The print defects guide relates repeating marks to the charge rollers, transfer roller, toner cartridge, and fuser. That comparison helps a technician narrow the likely source of a recurring image defect before choosing a replacement assembly.

Printhead, Fuser, and System Card Service

Mechanical registration and electronic oscillating-printhead alignment are separate procedures, with Quick Test alignment diagrams. Fuser coverage distinguishes Type 1 non-contact detacs from Type 2 full-contact detacs.

The NVRAM mismatch section explains why improper replacement of the operator panel and system card can leave the printer inoperable. The system-card procedure also warns that misaligned LVPS connections can cause damage.

Because printer servicing involves high-voltage electrical components and moving mechanical parts, qualified personnel should follow the manual's safety precautions during diagnosis and repair.

Paper Paths, Options, and Component Identification

Printer theory covers the media path, duplexing mechanisms, xerographic process, and printhead control. Separate T650 and T652/T654 duplex paper-path illustrations distinguish the external duplex arrangement from the internal duplex units.

The connector-location chapter contains a placeholder. Electrical diagrams are provided in the appended 4062-T650, 4062-T652, and 4062-T654 wiring sheets, which map system-card connectors to the LVPS, HVPS, main drive motor, and cooling fans.

Exploded parts views identify field replaceable units, including the high-capacity input tray and optional output assemblies. The RFID UHF section covers the option's firmware card, user flash card, interface card, cabling, and fuser wiper.

The preventive maintenance chapter lists expected component life, maintenance-kit versions, and maintenance-counter resetting. It specifies no lubrication requirements for these printers.

A Preview of Fuser Adjustment and Maintenance Data

These examples are a small selection of the adjustment and maintenance specifications in the manual.

For all covered models, the fuser-solenoid air gap is 4.5 mm ± 0.1 mm between the rear of the stator and the armature. The maintenance tables distinguish a 300,000-page interval for Type 1 fuser kits from 150,000 pages for Type 2 kits.

Searchable Text, Bookmarks, and Wiring Sheets

Search and diagram detail: The manual's body text is searchable, with embedded bookmarks covering the service chapters, parts catalog, print defects guide, and wiring diagrams. The three wiring sheets have no searchable labels; their small connector and pin markings are readable when enlarged.

Supplied as one printable, 572-page PDF in English: 568 pages of manual front matter, service content, parts information, and indexes, plus a one-page print defects guide and three wiring sheets. All four closing reference pages are included in the total.