Hi there! My name is***** am a computer professional with over 15 years of experience with both Mac and Windows computers, phones, tablets, and printers. It would be my pleasure to assist you with this. May I ask is the Citizen brand CTS300? If so, for this printer the ERROR LED Lights or blinks when paper is empty or in case of a failure. The interval length of the blinking shows the type of error. Can you tell me please how many times it blinks before it pauses and starts blinking again?
Please click below to access an electronic version of the user manual for the Citizen CTS300 http://www.citizen-systems.co.jp/english/support/download/printer/document/user/data_box/CT-S300UME_201.pdf.
You can save it to your computer or print it out. It may prove useful not only now but also in the future.
Please note that on page 27 of the manual there is a list of the blink patterns and and explanation of what each blink pattern means.
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