Brother DCP-7057 Service Manual page 83

■ Error code 7B
These errors do not usually occur in the normal use. The conceivable causes are noise around
the installation site, fluctuation of the power supply voltage, and failures in the software.
Print Unable 7B
Turn the power off and then back on again.
Error, which cannot be specified, occurs.
Error code 7C
---
Error, which cannot be specified, occurs.
<User Check>
• Turn OFF the power switch, and turn it ON again after a while.
Step
1 Main PCB failure
■ Error code 7D
Drum Error
Open the Front Cover and slide the green tab across the Drum Unit
several times.
Detected unusual discharge of the corona wire due to dirt on the drum unit.
<User Check>
• Clean the corona wire of drum unit.
• Turn OFF the power switch, and turn it ON again after a while.
Step
Dirt on the electrode of the drum
1 unit and on the machine
High voltage power supply PCB
2
failure
3 Main PCB failure
Cause
Cause
2-46
Remedy
Replace the main PCB ASSY.
Remedy
Clean the dirt on the contact points of the
both electrodes.
(Refer to Fig. 2-11, Fig. 2-12)
Replace the high voltage power supply
PCB ASSY.
Replace the main PCB ASSY.
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