How to: Perform a self-test on a LabelWriter 450

Performing a self test can help you determine basic functionality, such as confirming the print head in the LabelWriter is functioning correctly, that the label sensor is working, and that the device is receiving power. 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.

This test can be confirmed in conjunction with the label feed button. Pressing this once should feed one label. If no label is fed, or more than one label is fed, then this indicates a problem with the printer. Doing this isolates the printer from the PC, thus ruling out connection or software problems.

LabelWriter 400 or 450 Series (Including the Duo and Twin Turbo)

1. Ensure the LabelWriter is powered on (solid blue light on the front) 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.  Once the blue light begins to flash, immediately let go of the form feed button. The LabelWriter should be in self test mode, printing labels with varying line patterns.
3. To end the self test, press the form feed button. 

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 this
   through the LabelWriter. This will help to clean the internal mechanism.  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 under warranty.