Brother MFC640CW - Ghost; Overlapping or Separated Lines over the Whole Page; Stained Leading Edge of Recording Paper; White Horizontal Streaks

9-34 Confidential
Problem Action to be taken
(10) White horizontal streaks
• Perform the head purging operation several times to remove
dust or air bubbles from its nozzles.
• Replace the head/carriage unit.
• Check the paper feed-related rollers.
• Perform the print head skew compensation with the head screw
adjuster knob. Refer to Chapter 3, Section 3.2.2.4.
• Clean the head caps and wiper of the maintenance unit with a
Rubycel stick. For the cleaning procedure, refer to Chapter 7,
Section 7.1 "CLEANING THE MAINTENANCE UNIT."
(11) Stained leading edge of
recording paper
Printer
• Press the Ink button to perform a head cleaning operation.
• Check that the head/carriage unit is set into place.
(12) Overlapping or separated
lines over the whole page
• Adjust the paper feeding correction value of the paper feed
roller. (Refer to Chapter 6, Section 6.2, [ 4 ].)
(13) Overlapping or separated
lines at the trailing edge of the
recording paper
• Adjust the paper feeding correction value of the paper ejection
roller. (Refer to Chapter 6, Section 6.2, [ 4 ].)
(14) Ghost
VWXYZ
• Adjust the paper feeding correction value of the paper feed
roller and paper ejection roller. (Refer to Chapter 8, Section
8.4.11.)
• Correct the positioning error of the head/carriage unit. (Refer
to Chapter 6, Section 6.2, [ 3 ].)
• Replace the PF encoder disk.
• Replace the PF sensor PCB.