Service manual

Troubleshooting
Samsung Electronics 4-25
Dark selected
via RCP?
Change to
Normal and test
Works cor
with -300V of Bias
voltage?
Works
correctly after
replaced LSU?
Repair or replace the defective
component
The power of LSU is set
high or internal problem
-> Replace LSU or adjust
volume
Same at Normal?
END
NO
NO
NO
Toner over supply due to the
adjustment fault of metering
blade in developer
-> Replace developer
NO
YES
YES
YES
YES
Dark Image
Digital Printer
Digital Printer
Digital Printer
Digital Printer
Digital Printer