Brother GT-3 Series Service Manual page 104

Flow 4 (Clogging inside the Print Head?)
From previous flow
The Maintenance unit, Ink Supply Tube, or Ink
Supply unit may be faulty.
Print a solid pattern on A3 paper after "Powerful" Head cleaning.
Filter new?
YES
Significant misfiring
immediately after printing
started?
YES
Is weight of current Ink
Cartridge 250 g or
NO
Insert a new Ink Cartridge, execute "Powerful"
cleaning, and then print a solid pattern.
2.5 cc of ink used.
No problem with Ink Supply unit.
Powerful Cleaning
(up to 5 times)
Print a check pattern and count
the number of misfiring nozzles.
NO
All nozzles firing?
Problem solved.
(No PH replacement)
NO
Exchange Filter
NO
more?
NO
Significant misfiring
immediately after
printing started?
Max. 12.5 cc of ink used.
Repeating "Powerful"
cleaning 5 times does
YES
not resolve the
problem.
All nozzles
misfiring?
NO
YES
Ink may not be filled properly.
Go to Flow 5.
YES
Is the Ink Supply
Tube bent?
Straighten the Tube, execute
YES
"Powerful" cleaning, and then print a
solid pattern.
Significant misfiring
immediately after
NO
printing started?
Go to Flow 3.
GT-3 Series
4. Solving Print Quality Problems
Remaining ink qty may not
be measured correctly.
NO
YES
2.5 cc of ink used.
Tube clogging
Replace Print Head and
Ink Supply Tube.
YES
Go to Flow 6 to
replace Filter.
95