Brother MFC640CW - Dark; Light; Straight or Blurred Vertical Stripes

9-32 Confidential
Problem Action to be taken
(4) Light
At the scanner
Check the following components:
- CIS unit
- Main PCB
At the printer
Check the following components:
- Ink cartridges
- Head/carriage unit
- Main PCB
- Power supply PCB
- Head property info (to be installed to the main PCB from
the connected PC. Refer to Chapter 8, Section 8.4.16.)
- Maintenance unit
(5) Dark
At the scanner
Check the following components:
- CIS unit
- Main PCB
At the printer side
• Perform the head purging operation several times to remove
dust or air bubbles from its nozzles. If the problem persists,
replace the head/carriage unit.
Check the following components:
- Ink cartridges
- Head/carriage unit
- Main PCB
- Power supply PCB
- Head property info (to be installed to the main PCB from
the connected PC. Refer to Chapter 8, Section 8.4.16.)
- Maintenance unit
(6) Straight or blurred vertical
stripes
Scanner
Check the following components:
- CIS unit
- Scanner glass
Printer
• Check whether paper is coming into contact with any
components other than the ones it should during ejecting.
• Check the CR encoder strip for stains or scratches. (If the CR
encoder strip is not hooked properly, correct it.)