Samsung SCX-6320F/XEC Service Manual page 107

Troubleshooting
All Black
Digital Printer
Digital Printer
All black in
printing area?
YES
Is charge
voltage supplied
from HVPS?
YES
Is the
Hsync signal received
in LSU?
YES
Charge part's contact
is bad -> Repair or
replace the drum cartridge
Service Manual
7-10
Does the
NO video data line to LSU
transit to High/Low when
printing?
Replace LSU
NO
NO
NO
YES
Repair or replace HVPS
Replace LSU
Check the path among video
controller, engine board,
HVPS, LSU for the shortage
or open -> Repair or replace
the boards
Samsung Electronics