Epson Stylus Pro 4400 Service Manual page 197

EPSON Stylus Pro 4400/4450/4800/4880/4880C
UNEVEN PRINTING/POOR RESOLUTION
If the print quality is abnormal (uneven printing, diffused image, etc.), the
following items should be checked.
1. Perform the adjustment below with Adjustment Program.
1. Nozzle Bi-D Adjustment (p.393)
2. Auto Bi-d Adjustment (p.430)
3. Auto Uni-d Adjustment (p.401)
4. Check Platen Gap (p.410)
Execute Nozzle Check (p.436) and Alignment Check (p.437) above
adjustment. If print quality is still abnormal, go to next step.
2. If the trouble occurs only when the user is using a specific type of paper
(thick paper), carry out "User Paper Setting" using the panel setting
procedure. (By setting the information concerning the thickness of the
paper the user is using and correcting the print position (correction of
changes in the position where ink hits the paper surface due to differences
in paper thickness), avoid influencing the print position.)
3. If this problem occurs after replacing the BOARD ASSY., MAIN with a new
one:
Transfer the parameters on the old Main Board to the new board.
(p.409)
4. If the printer's condition is not improved by the above items (adjustments),
replace the following parts.
Printhead (p.285)
Printer Mechanism (SP) (p.242)
Troubleshooting
SMUDGED OR MARRED PRINTOUT (FRONT SIDE)
If smudging or marring occurs due to rubbing by the head, etc. on the paper's
printed surface, check the following items.
1. If smudging is occurring at the front end of the roll paper or at the rear end,
widen the margins at the front end and rear end. (Set the "PAPER
MARGIN" front end and rear end on "15mm".)
(If high duty printing was done close to the front end and rear end (margin
= 3mm), the paper will contain a large amount of ink and deformation of the
paper will be accelerated, and depending on the case, the paper will touch
the head.)
2. If paper with weak edges which cannot move smoothly along the paper
path is being used, Select "-4" for "SUCTION" in the "CUSTOM PAPER",
which is in the "Panel Setting".
3. If there is rubbing and smudging due to slow drying in printing of user
paper.
In the item "DRYING TIME" in the "CUSTOM PAPER", in "Panel Setting"
set the drying time (the time until auto paper cutting is carried out after
printing is finished. (Default: 0 second; Maximum: 10 seconds)
4. If the trouble cannot be resolved by the above methods, check the
following.
Pump Unit failure
Check to see if dust containing ink, foreign matters or paper is
adhering to the side surface of the head.
5. Extend platen gap.
NOTE: Be careful to decreasing image quality, if the platen gap is
Troubleshooting Based on Your Printout
extended.
Revision C
197