Brother MFC620CN Service Manual page 343

Problem
(4) Light
(5) Dark
(6) Straight or blurred vertical
stripes
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
- Maintenance unit
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
- Maintenance unit
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.)
9 - 3 0
Action to be taken
Chapter 8, Section
Chapter 8, Section
8.5.16.)
8.5.16.)
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