Fujitsu FI 5950 Service Manual

The Fujitsu FI 5950 is a high-performance dot matrix printer designed for heavy-duty business applications. This service manual covers technical specifications, maintenance procedures, troubleshooting guides, and repair instructions for qualified service technicians. The FI 5950 features high-speed printing, multiple paper handling options, and robust construction for reliable operation in demanding environments.

1. Technical Specifications 2. Safety Precautions 3. Installation Procedures 4. Mechanical Components 5. Electrical Systems 6. Print Head Maintenance 7. Paper Feed System 8. Control Panel Operations 9. Error Codes and Diagnostics 10. Parts Replacement Guide 11. Troubleshooting Procedures

Technical Specifications

Detailed technical specifications and performance characteristics of the Fujitsu FI 5950 dot matrix printer.

SpecificationDetails
Print Method24-wire dot matrix impact
Print SpeedUp to 600 characters per second
Paper WidthUp to 16 inches continuous forms
InterfaceParallel, Serial, and optional network
Character SetsMultiple international character sets
Buffer Memory128KB standard, expandable to 1MB
Power Requirements100-240V AC, 50/60Hz
Dimensions650mm (W) x 400mm (D) x 300mm (H)
WeightApproximately 25 kg
Operating Environment10-35°C, 20-80% humidity

Safety Precautions

Critical safety information for service technicians working on the FI 5950 printer.

  1. Disconnect power before performing any maintenance or repair procedures.
  2. Allow printer to cool before handling internal components.
  3. Use proper lifting techniques - printer weighs 25 kg.
  4. Wear anti-static wrist strap when handling electronic components.
  5. Keep hands clear of moving parts during operation.

WARNING! High voltages are present inside the printer. Only qualified technicians should perform internal repairs.

Installation Procedures

Step-by-step installation and setup instructions for the FI 5950 printer.

  1. Unpack printer and verify all components are present.
  2. Remove shipping restraints and protective materials.
  3. Install paper feed tractor units according to paper width.
  4. Connect interface cable (parallel recommended for Windows).
  5. Connect power cable and turn on printer.
  6. Run self-test to verify proper operation.
  7. Install printer drivers on host computer.

CAUTION! Ensure printer is on stable, level surface to prevent tipping.

Mechanical Components

Electrical Systems

Detailed electrical system specifications and testing procedures.

Power Supply: Input: 100-240V AC, 50/60Hz; Output: +5V DC, +24V DC, +35V DC

Main Board: 16-bit microprocessor, 128KB RAM, ROM firmware

Motor Drivers: Stepper motors for carriage and paper feed, DC motor for fan

Sensors: Paper-out sensor, home position sensor, ribbon sensor, temperature sensor

Testing Procedures: Use multimeter to verify voltage levels at test points. Check continuity of cables and connectors.

Print Head Maintenance

Print head cleaning, inspection, and replacement procedures.

  1. Power off printer and allow to cool completely.
  2. Open top cover and remove ribbon cartridge.
  3. Clean print head with isopropyl alcohol and lint-free swab.
  4. Inspect print wires for wear or damage.
  5. Check print head gap adjustment (0.35mm recommended).
  6. Test print quality using self-test pattern.
  7. Replace print head if print quality is unacceptable.

Tip: Regular cleaning extends print head life. Clean after every ribbon change.

Paper Feed System

Maintenance and adjustment of paper feed mechanisms.

  1. Adjust tractor units to match paper width.
  2. Set paper thickness lever according to forms type.
  3. Lubricate paper feed mechanism with specified grease.
  4. Check and adjust paper feed tension springs.
  5. Clean paper dust from feed rollers and sensors.
  6. Verify paper alignment using alignment marks.
  7. Test paper feed with various form types.

WARNING! Never force paper through feed mechanism. This can damage tractor pins.

Control Panel Operations

Control panel functions, indicators, and configuration procedures.

Buttons: POWER, LF/FF (Line Feed/Form Feed), LOAD, PAUSE, TEST

Indicators: POWER (green), READY (green), PAPER (red), ERROR (red)

Configuration: DIP switches for interface settings, character tables, and emulation modes

Self-test: Hold TEST button during power-on to print configuration and test pattern

Factory Reset: Power off, hold LF/FF and PAUSE, power on to reset to factory defaults

Error Codes and Diagnostics

Common error codes, their meanings, and resolution procedures.

Error CodeDescriptionResolution
E-01Carriage errorCheck carriage movement, clean rails
E-02Paper feed errorCheck paper path, clean sensors
E-03Print head temperatureAllow cooling, check thermal sensor
E-04Ribbon errorCheck ribbon installation
E-05Memory errorReset printer, check main board
E-06Power supply errorCheck power supply voltages

Parts Replacement Guide

Authorized replacement parts and installation procedures.

Note: Use only Fujitsu authorized parts for replacement to maintain warranty.

Troubleshooting Procedures

SymptomPossible CauseCorrective Action
No powerPower cable, fuse, power supplyCheck power source, replace fuse, test power supply
Poor print qualityPrint head, ribbon, gap settingClean/replace print head, replace ribbon, adjust gap
Paper jamsMisaligned tractors, worn rollersAlign tractors, clean/replace feed rollers
Communication errorsCable, interface, settingsCheck cable connections, verify interface settings
Carriage stallsObstructions, motor failureClear obstructions, lubricate rails, test motor

Service Contact: Fujitsu Technical Support: 1-800-FUJITSU

Parts Ordering: www.fujitsu.com/global/services/computing/peripherals/printers

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