Brother International MFC-P2000 Service Manual - Page 77

I-3 Completely blank Possible cause CIS harness connection CIS unit failure Sensor harness connection Main PCB failure Step 1 2 3 4 Check Is the CIS harness connected securely? Is the problem solved after the CIS unit is replaced? Is the sensor harness connected between the main PCB and the scanner sensor PCB securely? 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 Developing bias contact failure Drum unit Drum unit failure Scanner harness connection failure Main / Panel sensor PCB connection failure Laser unit failure Step 1 2 3 4 5 6 Check Are the developing bias contacts between the printer body and drum unit dirty? Are the drum shaft and drum electrode of the printer body connected correctly? Is the problem solved after the drum unit is replaced? Is the scanner harness connected securely? Is there any play in the connection? Are printing signals being input to the scanner? Is the problem solved after the main PCB or the panel sensor PCB replaced? Laser interlock lever damaged. Laser mirror is broken or loose. Result Yes Yes No Yes No Yes Yes No Remedy Clean the electrodes at both sides. Clean the shaft and the electrode. Check the connection between the shaft and the electrode. Replace the drum unit. Reconnect the connector properly. Replace the main PCB or the panel sensor PCB. Replace the laser unit. Replace the highvoltage power supply PCB. GND contacts (Fig.4-5) ➆ ➀ ➀ IV-8