Brother DCP-8110DN Service Manual page 80

Error code 4400
No Toner
Open the Front Cover, then install the Toner Cartridge.
The toner sensor detected that the toner cartridge was not set.
<User Check>
• Set the toner cartridge.
Step
Toner sensor PCB failure
1
2 Relay front PCB failure
3 Main PCB failure
Error codes 4500 to 4F00
These errors do not usually occur during normal use. The possible causes are noise around
the installation site, fluctuation of the power supply voltage, and failures in the software.
---
An unidentified error occurred.
Step
1 Main PCB failure
Error code 5000
Replace Parts
Drum
The number of rotations of the drum unit has reached the life limit. (Printing does not stop.)
<User Check>
• Prepare the drum unit.
Step
Replace the drum unit with a
new one and reset the drum
1 counter. If the error display is
not cleared, the main PCB is
faulty.
Cause
Refer to
(function code: 32)" in Chapter 5
sensor operation. If the sensor operation is
faulty, replace the toner sensor PCB ASSY.
Replace the relay front PCB ASSY.
Replace the main PCB ASSY.
Cause
Replace the main PCB ASSY.
Cause
Replace the main PCB ASSY.
2-35
Remedy
"1.3.10 Check sensor operation
Remedy
Remedy
to check the
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