Zebra ZM400 Error Code Invalid Head

Troubleshooting Steps for “Invalid Head” Error

1. Verify the Printhead’s Authenticity
   Ensure that the printhead installed is a genuine Zebra part. Non-Zebra printheads may not be recognized by the printer. If in doubt, replace the printhead with an authentic Zebra unit.
2. Check the Printhead Data Cable Connection
• Turn off the printer.
• Disconnect and then reconnect the data cable to the printhead.
• Ensure the cable connector is fully inserted into the printhead connector.
• Turn on the printer.

If the error persists, the printhead’s thermistor might be faulty, requiring professional service.

3. Ensure Proper Ribbon Loading in Thermal Transfer Mode

If you’re using thermal transfer media, verify that

• The ribbon is correctly loaded.
• The ribbon sensor is not obstructed by the media.
• The printer is set to thermal transfer mode.

Incorrect ribbon handling or sensor issues can lead to the “Invalid Head” error.

4. Perform a Printer Calibration

Calibrate the printer to ensure proper media and ribbon detection:

• Turn off the printer.
• Hold down the Feed button.
• Turn on the printer while continuing to hold the Feed button.
• Release the Feed button when the printer starts calibrating.

This process helps the printer recognize the label and ribbon correctly.

5. Inspect for Firmware Issues

Outdated or corrupted firmware can cause various errors. Check Zebra’s official support site for firmware updates