How to perform a self-test on a Labelwriter 400 / 450 series label printer

Performing a self test can help you determine if the print head in the LabelWriter is functioning properly. During the self test, the LabelWriter will print labels with varying line patterns. Broken lines or gaps on the label during the self test can indicate a problem with the LabelWriter.

LabelWriter 400 or 450 Series Including the Duo and Twin Turbo

1. Ensure the LabelWriter is powered on (solid blue light on the front of the LabelWriter) with labels currently loaded.
2. Press and hold down on the form feed button, after about 5-10 seconds the blue light will begin to flash.
3. Once the blue light begins to flash, immediately let go of the form feed button.
4. The LabelWriter should be in self test mode, printing labels with varying line patterns.

To end the self test, press the form feed button. The self test will not end automatically, you must press the form feed button to end the self test.

If the LabelWriter feeds out labels with broken lines or gaps during the self test, please try the following:

1. Each LabelWriter is shipped with a cleaning card. Feed the cleaning card through the LabelWriter. This will help to clean the internal mechanism. If for any reason you do not have this cleaning card, you may purchase them directly from DYMO using the following part number: 60622. Afterwards, re-try the self test.
2. Replace the label stock with new DYMO labels and re-try the self test.
3. If the problem persists, please contact DYMO Technical Support to arrange a Return Material Authorization (RMA).