In a warehouse or a dispatch area, the label printer sets the pace. When it starts printing faint labels, blank labels or labels that land across the gap, orders back up behind it. Most of these faults have a short list of causes. Some you can check yourself in a few minutes; others need a technician and a part. Here is how to tell which is which, for Zebra printers and for most other thermal label printers.
Faint or patchy print
Faint print usually comes down to one of four things: the print darkness is set too low for the labels you are using, the printer is set for the wrong media type, the printhead is dirty, or the printhead is worn. Check the darkness setting first, in the printer menu or the driver, and print a test label. If a new roll of labels or ribbon has just gone in, make sure it matches what the printer is set for. A dirty printhead can be cleaned with a printhead cleaning pen or isopropyl alcohol, with the printer switched off, following the steps in the user guide. If the print is still faint after cleaning, the printhead is likely worn and needs replacing.
Blank labels
Blank labels are almost always a media setting. Direct thermal labels darken with heat and need no ribbon. Thermal transfer labels need a ribbon, loaded the right way round, with the ink side facing the label. If the printer is set for thermal transfer with no ribbon, or the ribbon is loaded inside out, labels feed through blank. Check the ribbon path against the diagram inside the printer cover and check the media type setting.
White lines through the print or the barcode
A thin white line running the length of every label is a printhead fault. Either something is stuck to the head, or some of the tiny heating dots across the head have failed. Cleaning can fix the first. The second only goes away with a new printhead. This is the fault that matters most in a warehouse, because a white line through a barcode is what stops it scanning at the next step.
Labels skipping, creeping or printing across the gap
When labels start printing over the gap, or the printer feeds two labels for every one it prints, the printer has lost track of where each label starts. This happens most often after a change of label size or roll. Run the media calibration from the printer menu or the feed button, as set out in the user guide for your model, and print a test label. If calibration does not hold, the media sensor may be dirty or faulty, or the platen roller may be worn and letting the labels slip.
Head open or media out when everything is closed
If the printer reports the head is open when it is closed, or says it is out of labels with a full roll loaded, the fault is usually a sensor, a latch or a cable. These are not things to fix with a screwdriver on the packing bench. Call us and a technician will find which part has failed and replace it on site.
Strange characters instead of a label
Pages of odd characters, or a label printed in the wrong size, usually follow a change to the computer or software sending the job: a new driver, a new label template or a system update. Zebra printers understand their own printer language, and a job sent in the wrong language prints as text. Check the driver and the printer language setting before anything else.
When to call a technician
- White lines through the print that cleaning does not remove
- Head open, media out or ribbon errors that will not clear
- Calibration that will not hold, or labels that keep drifting
- A worn or damaged platen roller
- Cutter, peeler or rewinder faults
- Any fault on a printer the dock cannot run without
Pro Printer Repairs repairs Zebra, SATO, Toshiba TEC, Brother, Epson and Citizen label printers on site. The technician fixes the printer where it is used, then prints and scans test labels from your own system before leaving. See Zebra printer repairs, or label printer repairs in Brisbane, on the Gold Coast and on the Sunshine Coast. Or call 1300 206 002 and tell us what the printer is doing.