Brother MFC-7240 - Poor Fixing

2-68
Confidential
 Poor fixing
 Completely blank
<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. 2-7.)
- Remove the elastic band from the drum unit.
Step Cause Remedy
1 Fuser unit failure Replace the fuser unit.
2 Laser unit failure Replace the laser unit.
3
Low voltage power supply PCB
failure
Replace the low voltage power supply PCB
ASSY.
4 Main PCB failure Replace the main PCB ASSY.
<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.
Step Cause Remedy
1
Dirt on electrodes of the drum unit
and those of the machine
Clean the electrodes of the drum unit and
those of the machine. (Refer to Fig. 2-10
and Fig. 2-11.)
2
Connection failure of the scanner
harness of the laser unit
Reconnect the scanner harness of the laser
unit.
3 Laser unit attachment failure Reattach the laser unit.
4 Laser unit failure Replace the laser unit.
5
High voltage power supply PCB
failure
Replace the high voltage power supply PCB
ASSY.
6 Main PCB failure Replace the main PCB ASSY.