Brother FAX-2840 Service Manual page 74

Error code 7B and 7C
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.
---
An unidentified error occurred.
<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 blue tab across the Drum Unit several times.
Detected discharge that may be attributable to dirty corona wire on the drum unit.
<User Check>
• Clean the corona wire of the drum unit.
• Turn OFF the power switch, and turn it ON again after a while.
Step
Dirt on electrodes of the drum
1 unit and those of the machine
High voltage power supply PCB
2
failure
3 Main PCB failure
Error code 7E
This error does 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.
---
An unidentified error occurred.
<User Check>
• Turn OFF the power switch, and turn it ON again after a while.
Step
1 Main PCB failure
Cause
Replace the main PCB ASSY.
Cause
Clean the electrodes of the drum unit and
those of the machine. (Refer to
Fig.
Replace the high voltage power supply PCB
ASSY.
Replace the main PCB ASSY.
Cause
Replace the main PCB ASSY.
2-37
Remedy
Remedy
2-11.)
Remedy
Fig. 2-10 and
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