Brother International MFC-P2000 Service Manual - Page 78

I-4 All black Possible cause CIS harness connection CIS unit failure Sensor harness connection Main PCB failure Step Check 1 Is the CIS harness connected securely? 2 Is the problem solved after the CIS unit is replaced? 3 Is the sensor harness connected between the main PCB and the scanner sensor PCB securely? 4 Is the problem solved after the main PCB is replaced? Result Remedy No Reconnect the CIS harness. Yes Replace the CIS unit. No Reconnect the sensor harness. Yes Replace the main PCB. Possible cause Corona failure Harness connection High-voltage power supply PCB Ditto Main PCB Panel sensor PCB Step 1 2 3 4 5 6 7 Check Is the corona wire of the drum unit broken? Are the electric terminal springs in the printer body and the electrode on the bottom face of the drum unit dirty? Is the laser unit connected with the panel sensor PCB correctly? Is the problem solved after high-voltage power supply PCB replaced? Perform the same check as in step 3. Is the problem solved after main PCB is replaced? Is the problem solved after the panel sensor PCB is replaced? Result Yes Yes No Yes Yes Yes Yes Remedy Replace the drum unit. Clean the terminals in the printer and on the drum. Check the harness connection between the laser unit and the panel sensor PCB. Replace the highvoltage power supply PCB. Replace the panel sensor PCB. Replace the main PCB. Replace the panel sensor PCB. GND contacts (Fig.4-5) ➅ IV-9