Brother International DCP 8040 Service Manual - Page 246

I-11 Faulty registration MFC-8440/8840D/8840DN, DCP-8040/8045D/8045DN SERVICE MANUAL Possible cause Excessive paper load Print paper Rear registration sensor position incorrect Step 1 2 3 4 Check Is the paper loaded in the paper tray more than 27mm high? Is the specified weight of the recommended paper being used? Is the first printing position within ±1mm of the tolerance specification? Is the rear registration sensor off from the correct position? Result Remedy Yes Instruct the user to keep paper loads below 27mm in depth. No Recommend to use the specified types of paper. Yes Adjust the Y offset by using the utility software supplied. Yes Reposition the sensor to the correct position. I-12 Poor fixing Possible cause Print paper Toner sensing failure (When printing is faint.) Step Check 1 Is thick paper of more than 43lb being used? 2 Is the problem solved by replacing the drum unit or the toner cartridge? Fixing unit thermistor failure Low-voltage power supply PCB failure 3 Is the thermistor fitted correctly? 4 Is the problem solved by replacing the low-voltage power supply PCB? Result Remedy Yes Recommend to use the specified types of paper. Yes 1) Toner is empty. 2) The toner sensing is defective. Clean the toner sensor. 3) If the wiper in the toner cartridge is broken, replace the toner cartridge with a new one. No Fit the thermistor correctly. Yes Replace the low-voltage power supply PCB. 6-43