G Series GC Models: Calibrating the Printer

Article ID: 32096132

Issue / Question

Why is the red light flashing?

Why is there a skip in the printing of labels?

How to calibrate the printer?

Applicable To

GC420t, GC420d

Resolution / Answer

This information is useful for resolving issues such as:  

  • Feed button red light flashing.
  • The printer prints then skip a label or are skipping labels.
  • The print is overlapping onto the next label.
  • The print position is drifting up and down on the labels.
  • The labels stop printing in random locations.
  • The red light flashes when printing labels.

Common Issues and Resolutions


Problem Resolution

Flashing Red Light

NOTE Verify the ribbon core is fully seated on the supply spindle hub notches. The left side of the ribbon spool should have two notches on it. These notches should mate snuggly with the keyed areas to prevent a flashing red-light error. 
View Image.
  • Verify if the correct setting is configured for the media type.
    • Use the Mark Sensor for media with a black bar on the backing.
    • Use the Gap/Notch (Transmissive) Sensor for the gap, notch, or hole media. 
    • Refer to Media Identification.
  • Perform Calibration.
  • Defaulting the printer.
    • Reconfiguration to the default setting is required when using black mark media.
    • Refer to Factory Defaults under the Action section.
  • IIf the problem persists, a Media Sensor Profile can be sent to Tech Support for further analysis. 
NOTE Press the FEED button after calibrating. If one label feeds each time the FEED button is pressed, then the printer is properly calibrated. Verify that the Software/Driver settings do not change the calibrated values or printer configurations
Labels are skipping or 
the print image is wandering                                                      
  • Check Media Loading and assure the guides are keeping the media aligned.
  • Verify the printer is set to the correct Media Type.
    • The printer will not track Top-of-Form when Continuous media is used.
    • Use the Mark Sensor for media with a black bar on the backing.
    • Use the Gap/Notch (Transmissive) Sensor for the gap, notch, or hole media.
    • Refer to Media and Ribbon Identification.
  • Verify the labels are compatible. Refer to the Media Specifications.
  • Press the FEED Button. If one label feeds each time it is pressed, check your label format or Driver/Software for the source of the problem. 
NOTE If you are using EPL Label Formats, assure the label length is set correctly. A label length setting longer than the calibrated length will result in an extra label for each label printed.
  • Set to Factory Default and verify printer has calibrated correctly.
  • Perform Manual Calibration
    • Refer to User Guide: Manual Media Calibration.
    • If the problem persists, a Media Sensor Profile can be sent to Tech Support for further analysis.
    • You can obtain the graphical profile of the media sensing from the user guide.


Additional Information

Be aware that software or driver settings can override printer settings for Media Type, Label Length, etc.

+ Product Codes

  • G-Series GC Desktop Printers
  • GC420d Desktop Printer
  • GC420t Desktop Printer