2003 Canon PC-D320 / PC-D340 / FAX-L400 Copier Service Manual (P/N HY8-10AX-000)

Canon's service manual for the PC-D320, PC-D340 and FAX-L400 is publication HY8-10AX-000, Revision 0 (January 2003). It covers the printer engine, document scanner and model-specific communication hardware.

• Document feed: Disassembly of the separation roller assembly, separation guide unit and document feed roller for the PC-D340/FAX-L400 Automatic Document Feeder (ADF).

• Recording section: Pick-up roller and separation pad replacement, cassette and multi-purpose tray feed diagnosis, and paper-jam detection.

• Fixing assembly: Removal procedures, cleaning instructions, pressure-roller nip-width inspection, and fixing-heater and thermistor fault diagnosis.

• Scanner service: Contact-sensor and drive-motor troubleshooting, scan-quality checks, and gain auto adjustment after relevant component replacement.

• Electrical and fax tests: DRAM, sensor and operation-panel tests, plus FAX-L400 modem/NCU checks and communication fault isolation.

• Drawings and flowcharts: Parts Layout, Sensors Layout and Printing Range drawings, wiring diagrams, test mode flowcharts and service data flowcharts.

This manual is intended for qualified service personnel handling installation, maintenance and repair.

Paper Feed and Image-Quality Diagnosis

For a paper-feed jam or scanner fault, the troubleshooting sections distinguish recording-paper transport, document transport and image-quality problems. Sensor timing separates pick-up delay jams from delivery stationary jams, helping you narrow down the affected part of the paper path.

Print-test guidance explains how a clean test print combined with a poor copy points toward the scanning section. Illustrated print-defect examples connect visible symptoms to checks involving the photosensitive drum, transfer charging roller and fixing components.

Disassembly, Fixing Service and Scanner Adjustment

Illustrated disassembly focuses on components that need replacement relatively often. For other assembly and disassembly work, Canon refers to a separate Parts Catalog, which is not included. The laser/scanner unit is not intended for internal field disassembly.

Gain auto adjustment is specified after replacement of the SCNT board, contact sensor or platen glass. Fixing coverage includes heater temperature-control failure criteria and checks for poor fixing.

Handling cautions address oil contamination of the transfer charging roller, fixing film and pressure roller, which can cause print defects and jams. The manual also warns that incorrect grease can deform plastic and rubber parts.

Servicing requires the manual's precautions for electrical isolation, hot fixing components and laser exposure.

Control Boards and FAX-L400 Communication

PCB layouts distinguish the shared SCNT, ECNT and OPCNT boards, the PC-D320/PC-D340 USB board, and the FAX-L400 NCU and USB-MJB boards. The specifications include USB connector pin assignments, electrical interface reference values and operating-environment requirements.

FAX-L400 diagnostics cover modem signals, tone/DTMF reception and communication troubleshooting. Printer fault guidance addresses E000 fixing-unit failures, E100 laser/scanner failures and E805 fan failures.

Service-data scope: The manual provides service reports, country-specific defaults and explanations of newly added SSSW settings. Detailed explanations of other service soft switches require the separate G3 Facsimile Service Data Handbook, which is not included.

The Wiring Diagram (PDF p. 196) carries an AC 120V label that conflicts with the supply variants listed on the cover.

Examples of Fixing Checks and Paper Capacity

These are a few of the service and paper-handling specifications in the manual.

Pressure-roller nip width is specified as 6.0-7.6 mm at the center and both sides. This is an inspection range; the fixing unit does not allow nip-pressure adjustment.

Print-defect guidance associates recurring marks at approximately 56.5 mm with the fixing film and 62.8 mm with the pressure roller. The cassette specification is approximately 250 sheets of 64 g/m² paper.

PDF Navigation, Diagram Detail and Page Count

Text search and diagram access: The main text is searchable, but embedded report samples are not. There are 31 bookmarks for chapters and selected sections. Small connector and pin labels in the wiring diagram are readable when enlarged.

One printable, English-language 214-page PDF. The total includes 188 content pages, 8 cover/front-matter pages, 5 chapter dividers, 12 blank or intentionally blank pages, and 1 back cover.