samsung scx 8123 problem when scanning HELP!!!

[DISC]

Hello

I have a problem when scanning from the glass and adf, the printer prints correctly but when I scan or copy a document, many vertical stripes or blank areas appear. I have made an autotune from service mode and on all occasions it gives me a scanning error. The firmware is updated to the latest version. What may be causing the problem?
Impression sample photos

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Thanks!!Thanks for your cooperation

[living]

Hello
clean the document glass.
as well as the scanner led.
if the problem remains replace the scanner led