Brother MFC-8220, Service Manual

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MFC-8220
SERVICE MANUAL
6-33
I-2 Dark
Possible cause Step Check Result Remedy
Ground
contacts
Corona wire
failure
(contact failure) 1 Are the charge electrodes
between the machine and the
drum unit dirty? Yes Clean both electrodes.
(3)
Drum unit failure 2 Is the problem solved after
replacing the drum unit? Yes Replace the drum unit
with a new one.
Toner cartridge
failure 3 Is the problem solved after
replacing the toner cartridge? Yes Replace the toner
cartridge with a new
one.
High-voltage
power supply
PCB failure 4 Is the connections of the
connector between the high-
voltage power supply PCB and
the engine PCB secured
correctly? Yes Replace the high-
voltage power supply
PCB.
Main PCB
failure 5 Are there any disconnected
connectors? No Replace the main
PCB.
Engine PCB
failure 6 Are there any disconnected
connectors? No Replace the engine
PCB.
User Check
(1) Check the paper used meets the recommended paper specifications.
(2) Check the machine’s environment. High temperature and high humidity
conditions can increase the amount of background shading.
(3) Clean the corona wire with the wire cleaner.
(4) Try installing a new toner cartridge or drum unit.