Error code 221 on Ricoh Aficio Color Copier?

PLEASE HELP.
MY RICOH COPIER SHOWS ERROR SC 221.
WHAT IS THIS ERROR CODE TELLING ME.
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OK.

 Error Code SC 221
This code is a Scan length detection problem.
1.Disconnected Sychronization Detector
2.Bad LD-Unit/BICU Board

In this problem you need to replace the Laser Diode & Laser Sync detect board.
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THANK YOU.
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