А доку почитать?
https://easeofaccess.adc.datalogic.com/public/marketlit/Send.aspx?file=R44-2747A
Цитата: Upon startup, if the scanner flashes its indicator LED or sounds an unexpected series of beep tones (other than normal power-up indications), this means the scanner has not passed its automatic Selftest and has entered FRU1 isolation mode. If the scanner is reset or the trigger is pulled, the sequence will be repeated. The following table describes the LED flashes/beep codes associated with an error found.
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NUMBER OF LED FLASHES/ BEEPS ERROR
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6 Main PCB
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