Brother International MFC-P2000 Service Manual - Page 75

I-1 Light Possible cause Main PCB failure Laser unit failure Step 1 2 Check Is the problem solved after the main PCB is replaced? Is the problem solved after the laser unit is replaced? Result Remedy Yes Replace the main PCB. Yes Replace the laser unit. Possible cause Toner sensing failure (printer side) Toner sensing failure (toner cartridge side) Drum connection failure High-voltage power supply PCB failure Panel sensor PCB or main PCB failure Laser unit failure Step 1 2 3 4 5 6 Check Can printing be started with the drum unit removed? Is the problem solved when 4 or 5 pages are printed after the toner cartridge is replaced with a full one? Are all the contacts (HV, GND) connected when the drum unit is installed? Check the harness connection between the high-voltage power supply PCB and the panel sensor PCB. Perform the same check as step 4 above and also between the panel sensor PCB and the main PCB. Is the problem solved by replacing the laser unit? Result Yes Yes No No No Yes Remedy Toner sensor failure. Check if the toner sensor needs cleaning and check the toner sensor connection. The wiper of the toner cartridge is defective, or replace the toner cartridge. Clean contact electrodes both in the printer body and on the drum unit. If the connection is normal, replace the high-voltage power supply PCB. Replace the panel sensor PCB or the main PCB. Replace the laser unit. GND contacts (Fig.4-5) ➀ IV-6