Poor Fixing - Brother DCP-7055 Service Manual

■ Poor fixing

Step
1 Fuser unit failure
2 Laser unit failure
Low voltage power supply PCB
3
ASSY failure
4 Main PCB failure
■ Completely blank
Step
Dirt on the electrodes of the drum
1 unit and the machine body
Scanner harness of the laser unit
2
connection failure
Laser unit not assembled correctly
3
4 Laser unit failure
High voltage power supply PCB
5
ASSY failure
6 Main PCB failure
User Check
• Check the machine's environment. High temperature and high
humidity or low temperature and low humidity conditions can cause
this problem.
• Clean the corona wire of drum unit.
• Replace the drum unit with a new one.
• Replace the toner cartridge with a new one.
• Return the green envelope levers to the home position. (Refer to
Fig. 2-8.)
• Remove the elastic band from the drum unit.
Cause
User Check
• Check the machine's environment. High temperature and high
humidity or low temperature and low humidity conditions can cause
this problem.
• Clean the corona wire of drum unit.
• Replace the drum unit with a new one.
• Replace the toner cartridge with a new one.
• Remove the elastic band from the drum unit.
Cause
2-83
Remedy
Replace the fuser unit.
Replace the laser unit.
Replace the low voltage power supply PCB
ASSY.
Replace the main PCB ASSY.
Remedy
Clean the electrodes of the drum unit and
machine body. (Refer to
12.)
Reconnect the scanner harness of the
laser unit.
Assemble the laser unit correctly and
secure the screw.
Replace the laser unit.
Replace the high voltage power supply
PCB ASSY.
Re-assemble the main PCB ASSY.
Fig. 2-11, Fig. 2-
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