I Have Ricoh 4000 giving SC-220 after cleaning LD please guide

https://printcopy.info/?mod=erc&brand=Ricoh&model=MP5000&code=220

Sc 322 is laser synchronization error Possible Cause : 1- Poor connection between the LD unit and the BICU board 2-Damaged cable between BICU and LD unit 3-LD unit out of position 4-LD unit defective 5-BICU board defective the first thing u can do is clean the laser unit , it could be dirty

SC 220 - The Laser Diode Unit has failed
[Action]
Replace the Laser Diode Unit. Part Number B2471859.

LD error
LD error continues for 0.5 seconds. (After LD error is detected, a release of LD error is written to the GAVD circuit during monitoring.).

• LD unit defective

como quitar error sc324

sc220 means laser synchronizing detector board, (used to determine the start timing of laser writing), does not send asignal while the polygon motor operates normally and the LD
mirror in laser may be stink clean it carfully and clean small board synchro which detect invisible laser beam

sc 305 means pcr primary charge roller did'nt work correctly that means did't give sufficient charge to drum unit possible causes pcr defective

sc326 is a laser synchronization error. The problem is usually caused by the laser sync detection board or the LD unit.

LD unit, or BICU board....Do LD pitch adjustment -both 400 and 600dpi

sometimes the plastic of the laser is turned by the heat proves to relax and to fit the screw that holds the laser unit that is of the side of the drum while it raises a millimeter with a screwdriver, this sometimes works.
Verifies that the glasses and mirrors well be positioned correctly.
Other

Poor connection between the laser
synchronization detector board and
the LD unit.
Laser synchronization detector board
out of position
Laser synchronization detector board
defective
LD unit defective

Never heard of this happening to five machines before.  Check the connections in the laser unit.