User guide
COBISS System Management  Zebra GK420t User Guide 
© IZUM, 18. 3. 2013, VIF-NA-20-EN, V1.0  7/18 
Figure 13 : Final loading of the black ribbon cartridge 
2.5  Resetting printer  
Once the media roll is placed and the black ribbon cartridge loaded, go through the following 
steps (make sure that the printer’s cover is closed and the status light is green): 
1.  Turn off the printer. 
2.  Press and hold the FEED button. 
3.  Turn on the printer. 
4.  The green status light flashes in sequences: once, then in the two-flash-, three-flash- and 
four-flash sequence. 
5.  Release the FEED button after the four-flash sequence. 
6.  The printer starts calibration process and advances the label ribbon to the next label. 
7.  Once the calibration process is complete, turn off and on the printer. 
2.6  Status light 
Colour 
Status 
Explanation and solution 
None 
Printer is turned off. 
Green 
Solid green 
Normal functioning 
Orange 
Solid orange 
It lights up for about ten seconds 
immediately after the printer is turned on. 
If it lasts for more than ten seconds, the 
printer requires service. 










