Zebra Technologies GC420d

Replacing the Printhead

5/23/2012 GC420d™ User Guide P1052685-001

3. Slip the left end of the printhead spring into the left side of the latch bracket; then slide the

right end into the other side. The angle of the “V” fits into the indent on the top of the

printhead bracket.

4. Align the latch bracket up to the top case and ensure that the cable are not bent or pinched.

5. Replace the four screws that hold the latch bracket to the top case and use a #1 Phillips

driver to tighten them.

6. Clean the print head as described under Cleaning the Printhead onpage 49.

7. Reload media. Plug in the power cord, turn on the printer and print a status report to

ensure proper function. See Printing a Test (Printer Configuration) Label onpage 15

Contents

Main Page iii iv FCC Compliance Statement Environmental Management Page vi Who Should Use This Document How This Document Is Organized vii Contacts Contacts viii Document Conventions Contents x Page xii Introduction GC420d Thermal Printers Whats in the Box? Unpack and Inspect the Printer Your Printer Opening the printer Printer Features Page Status Light Page Getting Started Attaching Power Loading Roll Media Preparing Media Placing the Roll in the Media Compartment Page Page Printing a Test (Printer Configuration) Label 16 Pre-install Windows Printer Drivers PlugNPlay (PnP) Printer Detection and Windows operating systems 17 Universal Serial Bus (USB) Device Communications Serial Port and Windows operating systems Ethernet Connecting your Printer to a Computer Interface Cable Requirements Page 20 Serial Communications Autobaud ZPL ^SC Command EPL Y Command Resetting the Default Serial Port Parameters 2. While the status LED rapidly flashes amber and green, press the feed button. Serial baud, NO parity, 8 data bits, 1 stop bit and a HARDWARE and SOFTWARE (merged) data Page 23 After Your Printer is Connected Testing Communications by Printing Page Print Operations Determining Printer Configuration Long Term Printer In-activity or Storage Thermal Printing Modes of Printing Print Media Types Page Determining Thermal Media Types To perform a media scratch test, complete these steps: Replacing Supplies Adjusting the Print Width Adjusting the Print Quality Media Sensing Printing on Fan-Fold Media Page Printing with Externally Mounted Roll Media Externally Mounted Roll Media Considerations: Fonts and Your Printer Localizing the Printer with Code Pages Identifying Fonts in Your Printer Stand Alone Printing Sending Files to the Printer Print Meter EPL Line Mode Printer Options 40 Label Dispenser Option ^XA ^MMP ^XZ Page Page Zebra KDU Printer Accessory 44 KDU Plus Printer Accessory * - Not real values ( 45mA + 120mA + 25mA ) + 50mA <Max. Current Current Draw ZBI 2.0 Zebra Basic Interpreter Page Maintenance This section provides routine cleaning and maintenance procedures. Cleaning Cleaning the Printhead Media Path Considerations 51 Sensor Cleaning Platen Cleaning and Replacement Other Printer Maintenance Replacing the Printhead Page Page Page Page Troubleshooting Status Light Descriptions Status Light Error Resolutions Page Print Quality Problems No print on the label. The printed image does not look right. There are long tracks of missing print (blank vertical lines) on several labels. The printing does not start at the top of the label or misprinting of one to three labels. A ZPL label format was sent to, but not recognized by, the printer. A EPL label format was sent to, but not recognized by, the printer. Manual Calibration Troubleshooting Tests Resetting the Factory Default Values Communications Diagnostics Page Feed Button Modes Feed Button Modes Amber - Red Flashing Green Amber www.zebra.com Page Page Page Universal Serial Bus (USB) Interface Parallel Interface PRINTER DB-25 Pin No. Centronics Pin No. DB-25 to Centronics (Cable) Serial Port Interface Connecting the Printer to a DCE Device Page Page Page Page C 82 Managing Printer Configuration with ZPL Programming ZPL Printer Configuration Format ZPL Configuration Status to Command Cross-reference Page Page Printer Memory Management and Related Status Reports ZPL Programming for Memory Management