Brother DCP9040CN

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User Check

- Replace the toner cartridge or drum unit with a new one.

Step	Cause	Check	Result	Remedy
1	Developing bias voltage conduction failure	Are the electrodes on the drum unit and machine body dirty?	Yes	Clean both electrodes.
2	Scanner harness connection failure	Is the scanner harness connected securely?	No	Reconnect the scanner harness.
3	Engine PCB failure	Is the problem solved after replacing the engine PCB ASSY?	Yes	Replace the engine PCB ASSY.
4	Laser unit failure	Is the problem solved after replacing the Laser unit?	Yes	Replace the laser unit.
5	Transfer HVPS PCB failure	Is the problem solved after replacing the transfer HVPS PCB ASSY?	Yes	Replace the transfer HVPS PCB ASSY.
6	Charge HVPS PCB failure	Is the problem solved after replacing the charge HVPS PCB ASSY?	Yes	Replace the charge HVPS PCB ASSY

Image distortion

Step	Cause	Check	Result	Remedy
1	Laser unit not assembled correctly	Is the laser unit assembled into the machine securely? (Check if there is no gap.)	No	Assemble the laser unit correctly and secure the screw
2	Incorrect radiation angle of scanner diode Scanner motor rotation failure	Is the problem solved after replacing the laser unit?	Yes	Replace the laser unit.