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  1. ZD421 and ZD621 Series Desktop Printers User Guide
  2. Troubleshooting
  3. Resolving Alerts and Errors
  • ZD421 and ZD621 Desktop Printer User Guide
  • ZD421 and ZD621 Desktop Printer User Guide
  • About This Guide
    • Other Valuable Printer Resources
    • Zebra OneCare Printer Service and Support
    • Notational Conventions
    • Icon Conventions
  • Introduction
    • Link-OS 4 inch Desktop Thermal Printers
    • Common Desktop Printer Features
      • Link-OS 4-inch Desktop Printer Options
    • What’s in the Box?
    • Unpacking and Inspecting the Printer
    • What You Will Need to Print
    • Modes of Printing
    • Opening Your Printer
    • Closing Your Printer
  • Printer Features
    • Exterior Features of Your Printer
    • Inside the ZD421 Dual Capacity Ribbon Roll Printer
    • Inside the ZD621 Dual Capacity Ribbon Roll Printer
      • RFID Antenna Location – ZD621R Printers Only
      • Media Dancer – ZD621 Printers Only
    • Dual-Capacity Ribbon Chassis – Ribbon Roll Holders
    • Inside the ZD421 Direct Thermal Printer
    • Inside the ZD621 Direct Thermal Printer
    • Inside the ZD421 Ribbon Cartridge Printer
      • Accessing the Printhead of the ZD421 Ribbon Cartridge Printer
    • Label Dispenser Option (field-installable) – All Models
    • Cutter Option (field-installable) – All Models
    • Linerless Media Tear-Off Option – Direct Thermal Models Only
    • Linerless Cutter Option – Direct Thermal Models Only
    • Identifying Platen Drive Roller Types
    • Printer Power Supply Options
      • Attached Power Supply Base
      • Attached Battery Base and Battery
    • ZD621 Direct Thermal Locking Printer Feature – Healthcare Models Only
    • Zebra Print Touch for Near-Field Communications (NFC)
  • Controls and Indicators
    • User Interface
    • Standard Interface Controls
    • Meaning of the Indicator Light Patterns
      • Status – Typical Operating Conditions
      • Status – Printhead Operation
      • Status – Bluetooth Low Energy Option
      • Status – Ethernet (LAN) Option
      • Status – Wi-Fi (WLAN) Option
    • Battery Indicators and Controls
  • Install Hardware Options
    • Field-Installable Printer Accessories and Options
    • Printer Connectivity Modules
      • Accessing the Connectivity Module Slot
      • Installing the Serial Port Module
      • Installing the Internal Ethernet (LAN) Module
      • Removing Printer Connectivity Modules
    • Installing the Wireless Connectivity Module
    • Finding Your Printer's Media Access Control (MAC) Address
    • Media Handling Options
      • Removing the Standard Bezel
      • Installing the Label Dispenser
      • Installing the Standard Media Cutter
    • Media Roll Core Size Adapters
      • Installing the Media Roll Adapters
    • Installing the Attached Power Supply Base Options
    • Installing the Attached Battery Base Options
    • Installing the Battery into the Attached Power Base
  • Color Touch Display and Controls
    • Color Touch Display Printer Controls
    • Home Screen
      • Printer Status
      • Printer Info
      • Printer Wizards
      • User Menus
    • System Menu
      • System > Language
      • System > Program Language > Diagnostic Mode
      • System > Program Language > Virtual Device
      • System > Program Language > ZBI
      • System > Settings > Display Time Format
      • System > Settings > Password Level
      • System > Settings > Set Password
      • System > Settings > Power Up Action
      • System > Settings > Head Close Action
      • System > Settings > Screen Calibration
      • System > Settings > Restore Defaults
      • System > Settings > Print: System Settings
      • System > Energy Saving > Energy Star
    • Connection Menu
      • Connection > Networks > Reset Network
      • Connection > Networks > Primary Network
      • Connection > Networks > IP Port
      • Connection > Networks > IP Alternate Port
      • Connection > Networks > Print: Network Info
      • Connection > Networks > Visibility Agent
      • Connection > Wired > Wired IP Protocol
      • Connection > Wired > Wired IP Address
      • Connection > Wired > Wired Gateway
      • Connection > Wired > Wired MAC Address
      • Connection > WLAN > WLAN IP Protocol
      • Connection > WLAN > WLAN IP Address
      • Connection > WLAN > WLAN Subnet
      • Connection > WLAN > WLAN Gateway
      • Connection > WLAN > WLAN MAC Address
      • Connection > WLAN > ESSID
      • Connection > WLAN > WLAN Security
      • Connection > WLAN > WLAN Band
      • Connection > WLAN > WLAN Country Code
      • Connection > Bluetooth > Bluetooth
      • Connection > Bluetooth > Bluetooth Discovery
      • Connection > Bluetooth > Friendly Name
      • Connection > Bluetooth > Minimum Security Mode
      • Connection > Bluetooth > Specification Version
      • Connection > Bluetooth > MAC Address
      • Connection > Bluetooth > Bluetooth Auth. PIN
      • Connection > Bluetooth > Bluetooth Bonding
    • Print Menu
      • Print > Print Quality > Darkness
      • Print > Print Quality > Print Speed
      • Print > Print Quality > Print Type
      • Print > Print Quality > Label Type
      • Print > Print Quality > Label Length
      • Print > Print Quality > Label Width (Dots)
      • Print > Label Position > Collection Method
      • Print > Label Position > Tear Line Offset
      • Print > Label Position > Horizontal Label Offset
      • Print > Label Position > Vertical Label Offset
      • Print > Sensors > Manual Calibration
      • Print > Sensors > Label Sensor
      • Print > Sensors > Sensor Type
      • Print > Sensors > Print: Sensor Profile
      • Print > Print Station
      • Print > Applicator > Applicator Port Mode
      • Print > Applicator > Start Print Mode
      • Print > Applicator > Error on Pause
      • Print > Applicator > Applicator Reprint
    • RFID Menu
      • RFID > RFID Status
      • RFID > RFID Test
      • RFID > RFID Calibrate
      • RFID > Read Power
      • RFID > Write Power
      • RFID > RFID Antenna
      • RFID > RFID Valid Count
      • RFID > RFID Void Count
      • RFID > RFID Program Position
      • RFID > Read RFID Data
    • Storage Menu
      • Storage > USB > Copy: Files to USB
      • Storage > USB > Copy: Files to Printer
      • Storage > USB > Copy: Configuration to USB
      • Storage > USB > Print: From USB
      • Storage > Print Asset Lists
      • Storage > USB > Print from E:
  • Setup
    • Printer Setup Overview
    • Select a Location for the Printer
    • Install Printer Options and Connectivity Modules
    • Attaching the Printer to a Power Source
    • Media Preparation for Printing
      • Preparing and Handling Media
      • Media Storage Guidelines
    • Roll Media Types and Loading
      • Setting Media Sensing by Media type
      • Loading Media
      • Movable Sensor Adjustment
        • Adjusting the Movable Sensor for Black Marks or Notches
        • Adjusting the Movable Sensor for Web (Gap) Sensing
    • Loading Roll Media for Cutter Models
    • Thermal Transfer Roll Ribbon Loading
      • Loading Zebra Transfer Roll Ribbon
      • Loading Non-Zebra 300-Meter Transfer Ribbon
    • Loading the Ribbon Cartridge – ZD421 Ribbon Cartridge Printers Only
    • Running a SmartCal Media Calibration
    • Test Printing with a Configuration Report
    • Detecting and Recovering from a Media-Out Condition
    • Detecting and Recovering from a Ribbon-Out Condition
    • Connecting Your Printer to a Computer
      • Interface Cable Requirements
      • USB Interface
      • Serial Interface
      • Ethernet (LAN, RJ-45)
        • Assigning an IP Address for Network Access
        • DHCP for Personal Networks
        • Using Your Printer on a Managed Network
        • Print Server User ID and Password Defaults
      • Wi-Fi and Bluetooth Classic Wireless Connectivity Option
    • Update Printer Firmware to Finish Option Installations
    • What To Do If You Forget to Install the Printer Drivers First
  • Setup for Windows
    • Windows-to-Printer Communication Setup (Process Overview)
    • Installing the Windows Printer Drivers
    • Running the Printer Installation Wizard
    • Setting Up the Wi-Fi Print Server Option
    • Configuring the Printer Using ZebraNet Bridge’s Connectivity Wizard
      • Sending a ZPL Configuration Script to the Printer
    • Configuring the Printer Using Bluetooth
      • Connecting the Printer to a Windows 10 OS
    • After Your Printer is Connected
      • Test Printing with Zebra Setup Utilities
      • Test-Printing with the Windows Printer and Faxes Menu
      • Test-Printing with an Ethernet Printer Connected to a Network
      • Test-Printing with a Copied ZPL Command File for Non-Windows Operating Systems
  • Print Operations
    • Thermal Printing
    • Determining Your Printer’s Configuration Settings
    • Select a Print Mode or Collection Method
    • Adjusting the Print Quality
    • Adjusting the Print Width
    • Replacing Supplies while Using the Printer
    • Printing on Fanfold Media
    • Printing with Externally-Mounted Roll Media
    • Using the Label Dispenser Option
    • Using the Linerless Options
      • Linerless Printing
    • Sending Files to the Printer
    • Ribbon Cartridge Programming Commands
    • Printing with the Attached Battery Base and Battery Option
      • Uninterrupted Power Supply (UPS) Mode
      • Battery Mode
    • Printer Fonts
      • Identifying Fonts in Your Printer
      • Localizing the Printer with Code Pages
      • Asian Fonts and Other Large Font Sets
    • EPL Line Mode (Direct Thermal Printers only)
    • ZD621 Locking Printer Option
    • Zebra Keyboard Display Unit (ZKDU) – Printer Accessory
    • Zebra Basic Interpreter (ZBI)
    • Setting the Power Failure Recovery Mode Jumper
  • USB Host Port and Link-OS Usage Examples
    • USB Host
    • Using a USB Host for Firmware Updates
    • Files for Completing the Exercises
    • Exercise 1: Copy Files to a USB Flash Drive and Perform USB Mirror
    • Exercise 2: Print a Label Format from a USB Flash Drive
    • Exercise 3: Copy Files to/from a USB Flash Drive
    • Exercise 4: Enter Data for a Stored File with a USB Keyboard and Print a Label
    • Using the USB Host Port and Near Field Communication (NFC) Capabilities
      • Exercise 5: Enter Data for a Stored File with a Smart Device and Print a Label
  • Maintenance
    • Cleaning
      • Cleaning Supplies
      • Recommended Cleaning Schedule
      • Cleaning the Printhead
        • Cleaning the Printhead – ZD421/ZD621 Direct Thermal Printers
        • Cleaning the Printhead – ZD421/ZD621 Thermal Transfer Printers
        • Cleaning the Printhead – ZD421 Ribbon Cartridge Printers
      • Cleaning the Media Path
        • Cleaning the Media Path – Lower Half of ZD421/ZD621 Printers
        • Cleaning the Media Path – Upper Half of ZD421/ZD621 Direct Thermal Printers
        • Cleaning the Media Path – Upper Half of ZD421/ZD621 Thermal Transfer Printers
        • Cleaning the Media Path – Upper Half of ZD421 Thermal Transfer Ribbon Cartridge Printers
      • Cleaning the Cutter Option
      • Cleaning the Label Dispenser Option
      • Cleaning the Sensor
        • Cleaning the Sensor – Lower Half of the ZD421/ZD621 Printers
        • Cleaning the Sensor – Upper Half of ZD421/ZD621 Direct Thermal Printers
        • Cleaning the Sensor – Upper Half of the ZD421/ZD621 Thermal Transfer Printers
        • Cleaning the Sensor – Upper Half of the ZD421 Ribbon Cartridge Printers
      • Cleaning and Replacing the Platen
      • Replacing the Printhead
        • Replacing the Printhead – ZD421/ZD621 Direct Thermal Printer Models
        • Replacing the Printhead – ZD421/ZD621 Thermal Transfer Ribbon Roll Printer Models
        • Replacing the Printhead – ZD421 Thermal Transfer Ribbon Cartridge Printer Models
    • Updating Printer Firmware
    • Other Printer Maintenance
    • Fuses
  • Troubleshooting
    • Resolving Alerts and Errors
      • Alert: Printhead Open
      • Alert: Media Out
      • Alert: Ribbon In – ZD421 Ribbon Cartridge Printer Only
      • Alert: Ribbon Out
      • Alert: Ribbon Low – ZD421 Ribbon Cartridge Printer Only
      • Alert: Cutter Error
      • Alert: Printhead Over Temp
      • Alert: Printhead Shutdown
      • Alert: Printhead Under Temp
      • Alert: Out of Memory
    • Resolving Print Issues
      • Issue: General Print Quality Issues
      • Issue: No Print on the Label
      • Issue: Labels Are Distorted in Size or Print Area Start Position Varies
    • Communication Issues
      • Issue: Label Job Sent, No Data Transfer
      • Issue: Label Job Sent, Skips Labels or Prints Bad Content
      • Issue: Label Job Sent, Data Transfers, But No Print
    • Miscellaneous Issues
      • Issue: Settings are Lost or Ignored
      • Issue: Non-continuous labels act as Continuous labels
      • Issue: Printer Locks Up
      • Issue: Erroneous Ribbon Cartridge Faults
      • Issue: Battery Displays a Red Indicator
  • Tools
    • Printer Diagnostics
      • Power-On Self Test
      • Running a SmartCal Media Calibration
      • Printing the Printer and Network Configuration Reports (CANCEL Self Test)
        • Network (and Bluetooth) Configuration Report
      • Printing a Print Quality Report (FEED Self Test)
        • Printing a Print Quality Report
      • Resetting Non-Network Printer Configuration Settings to their Factory Defaults
      • Resetting the Printer's Network Settings to Their Factory Defaults
      • RESET Button Functions
      • Performing a Communication Diagnostics Test
      • Sensor Profile
    • Activating Advanced Mode
      • Manually Calibrating Media
      • Manual Print Width Adjustment
      • Manual Print Darkness Adjustment
      • Factory Test Modes
  • Interface Connector Wiring
    • Universal Serial Bus (USB) Interface
    • Serial Port Interface
  • Dimensions
    • Dimensions – ZD421/ZD621 Direct Thermal Printer Models
    • Dimensions – ZD421/ZD621 Thermal Transfer Printer Models
    • Dimensions – ZD421C (Ribbon Cartridge Thermal Transfer) Printer Models
  • Media
    • Types of Thermal Media
      • Determining Thermal Media Types
    • General Media and Print Specifications
  • ZPL Configuration
    • Managing the ZPL Printer Configuration
      • ZPL Printer Configuration Format and Reusable Files
    • Configuration Setting to Command Cross-reference
    • Printer Memory Management and Related Status Reports
      • ZPL Programming for Memory Management
  • Glossary
    • alphanumeric
    • backfeed
    • barcode
    • black mark media
    • calibration (of a printer)
    • collection method
    • configuration
    • continuous media
    • core diameter
    • diagnostics
    • die-cut media
    • direct thermal
    • direct thermal media
    • fanfold media
    • firmware
    • FLASH memory
    • font
    • gap/notch media
    • ips (inches-per-second)
    • label
    • label backing (liner)
    • label type
    • void
    • LCD (liquid crystal display)
    • LED (light emitting diode)
    • linerless media
    • mark media
    • media
    • media sensor
    • media supply hangar
    • non-continuous media
    • non-volatile memory
    • notched media
    • peel-off mode
    • perforated media
    • print speed
    • print type
    • printhead wear
    • Radio frequency identification (RFID) "smart" media
    • receipt
    • registration
    • ribbon
    • ribbon wrinkle
    • roll media
    • supplies
    • symbology
    • tag stock
    • tear-off mode
    • thermal transfer
Resolving Alerts and Errors

Resolving Alerts and Errors

The printer uses alerts to notify you that the printer needs attention.
Troubleshooting
Alert: Printhead Open
Alert: Media Out
Alert: Ribbon In – ZD421 Ribbon Cartridge Printer Only
Alert: Ribbon Out
Alert: Ribbon Low – ZD421 Ribbon Cartridge Printer Only
Alert: Cutter Error
Alert: Printhead Over Temp
Alert: Printhead Shutdown
Alert: Printhead Under Temp
Alert: Out of Memory

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