Brother MFC-8510DN, Service Manual

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Confidential
„
Error code 4400
The toner sensor detected that the toner cartridge was not set.
„ 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.
„
Error code 5000
The number of rotations of the drum unit has reached the life limit. (Printing does not stop.)
No Toner
Open the Front Cover, then install the Toner Cartridge.
<User Check>
• Set the toner cartridge.
Step Cause Remedy
1
Toner sensor PCB failure Refer to "1.3.10 Check sensor operation
(function code: 32)" in Chapter 5 to check the
sensor operation. If the sensor operation is
faulty, replace the toner sensor PCB ASSY.
2 Relay front PCB failure Replace the relay front PCB ASSY.
3 Main PCB failure Replace the main PCB ASSY.
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Step Cause Remedy
1 Main PCB failure Replace the main PCB ASSY.
Replace Parts
Drum
<User Check>
• Prepare the drum unit.
Step Cause Remedy
1
Replace the drum unit with a
new one and reset the drum
counter. If the error display is
not cleared, the main PCB is
faulty. Replace the main PCB ASSY.