Canon BJ-W7000 (1998) Bubble Jet Printer Service Manual (P/N QY8-1357-000)

This is Canon’s factory service manual for the BJ-W7000 large-format Bubble Jet printer, P/N QY8-1357-000, Revision 0, issued in October 1998.

PDF Bookmarks, Diagram Detail, and Page Count

Navigation and diagram detail: Embedded bookmarks jump to the contents, chapters, troubleshooting sections, and appendix. The page text must be read visually. Zooming helps with small pin numbers and component labels, though some closely spaced signal labels in the general circuit diagram remain hard to read.

The English-language download is one printable PDF with 274 pages, including the front and back covers, one printing-code page, 11 blank pages, and the appendix.

Carriage Repair, Ink Delivery, and Fault Diagnosis

The topics below are a selection from the manual. Other sections explain multipass printing and how to prepare the printer for transport.

• Carriage and drive: Step-by-step removal and reassembly coverage for the carriage, linear encoder, cartridge holder, flexible cables, and cutter, plus X- and Y-axis motor service and belt installation.
• Purge and ink supply: Purge motor and cam sensor removal, wiper solenoid service, waste ink tank replacement, and ink bottle case and buffer tube routing.
• Media transport: Platen, feed roller, and roll-media guide removal, with checks for cut-sheet detection, roll-media feed, path changes, and paper jams.
• Post-replacement adjustments: Carriage belt tension, media illumination lamp alignment, sensor gain and light intensity, and recalibration after controller board or sensor replacement.
• Fault isolation: Image-defect samples, symptom-based checks for operating faults, error-code tables, and the Setup List for reviewing stored errors and calibration offsets.
• Electrical reference: General circuit diagrams, controller board schematics, PCB layouts, and connector assignments for tracing power and signals between the boards and carriage.

Canon wrote this manual for service technicians who are expected to isolate printer faults and work with the relevant Canon service information.

Printhead, Media, and Mechanical Service

The operation chapter follows raster data from the IEEE 1284-B parallel interface and image memory to the engine controller and carriage. It covers SRL data, color and monochrome printing, and the Draft, Normal, and Enhanced modes. Head-drive diagrams show shift-register and latch logic, heater-enable signals, temperature sensing, and pre-pulse and main-pulse timing for the Bk/C/M/Y cartridges. The user-mode section explains when changing the drive frequency can address patterned ink dropout in one-pass printing.

Media tables cover cut sheets and rolls up to 36 inches wide, print margins, and the Y-axis automatic cutter. The media sensor section explains how the printer detects width, edges, and skew and how it uses printed patterns for automatic head alignment.

Assembly drawings show cover and control-panel removal, carriage lamp and sensor access, and image and engine controller board removal. A scratch or contact with a magnetic tool can compromise the linear encoder’s magnetized memory wire and disrupt carriage-position feedback. The ink tubing diagrams show the color-specific routing and joint positions that keep the ink channels correctly connected.

Calibration and Maintenance After Repair

After an engine controller PCB replacement, the manual brings the media retainer hook setting, media length and margin compensation, and room and head temperature compensation into one post-repair reference. Separate procedures identify which checks apply after replacing the carriage PCB, DC power supply PCB, volume PCB, media sensor, or illumination lamp. The communications section covers parallel-interface timing selection and the image-controller firmware update procedure using a separate firmware disk.

Canon calls for a waste ink tank inspection during service visits. The user-maintenance section covers head cleaning and gives a yearly wiper blade replacement guideline. The service-mode tables document the waste ink counter reset and identify purge checks, wiper height adjustment, and heat-run testing as factory settings.

Symptom Tables and Board Schematics

Image samples distinguish ink dropout, color dot shift, jagged or slanted lines, low density, displaced nozzles, axis striping, scaling errors, soft contours, and boundary smudging. The operating fault tables help isolate no-power, feed, carriage, purge, control-panel, head, jam, and ink-supply faults. For example, the feed checks help distinguish a cut-sheet sensor fault from a problem farther along the paper path.

The appendix includes 14 engine-controller sheets, 12 image-controller sheets, and seven carriage-board sheets. It also covers DC power, motor control, ink detection, the operation panel, and the volume board. Board maps locate adjustable resistors, LEDs, test pins, and short flexible cable terminals. Microprocessor coverage stops at external signals. The special tools list identifies the cover switch tool 6Y8-2123 and head temperature sensor tool 6Y8-2125.

Disconnect AC power before removing covers or boards. The manual flags static-sensitive PCBs, the sharp cutter blade, hot cartridge plates, and delicate printhead and electrode surfaces.

Media Sensor Calibration Examples

For automatic head adjustment on plain paper, the sensor gain procedure specifies 16.5 ± 0.1 V for lamp intensity and 12.0 ± 0.1 V for sensor sensitivity. The separate media-detection adjustment specifies 2.0 ± 0.05 V for lamp intensity with the carriage at the right end of the platen.