Troubleshoot Citizen CL-S621 error code 101. Technical causes, safe solutions, and preventative maintenance for retail card terminals.
Knowing if the error is reproducible helps isolate the fault.
Incorrect media can cause overheating.
Movement can damage cables.
Error 101 on the Citizen CL-S621 typically indicates a print head temperature issue or a problem with the print head thermistor circuit. Resistance values from the thermistor are outside acceptable parameters. Power fluctuations can influence thermistor readings. Signal attenuation from damaged ribbon cables is possible. Electrostatic discharge (ESD) during ribbon changes in dry environments may cause temporary sensor disruption.
Avoid touching the print head immediately after printing, as it may be hot. Safe Handling: Always unplug the printer from the power source before performing any cleaning or maintenance. Do not use excessive force when cleaning the print head or handling ribbon cables. ESD precautions are vital during ribbon replacement; ground yourself before handling.
Regularly clean the print head with a lint-free cloth.,Use recommended media and ribbon types.,Ensure proper ventilation around the printer to prevent overheating.,Implement cable strain relief measures to prevent damage to the ribbon cable.,Ground yourself before handling ribbon cables to minimize ESD risk, especially during dry weather.
Check for firmware updates on the Citizen support website. Outdated firmware can sometimes cause false error codes. If the error persists after cleaning the print head, use a magnifying glass to inspect for any physical damage to the thermistor on the print head assembly itself. If visibly damaged, the print head assembly may need professional repair or replacement.