Epson Stylus Pro 4910 Service Manual page 77

Epson Stylus Pro 4900/Epson Stylus Pro 4910
Symptom
Horizontal bandings (black/white lines or
uneven color) can be seen.
TROUBLE SHOOTING
Table 2-3. Print Quality Troubles
Cause
The print setting is not proper.
The printhead has not been adjusted
properly.
The paper feed amount is not proper.
Adjustment failure of the PG
PF Scale/PF Encoder cannot be
encoded properly.
The tension of the PF Timing Belt is not
proper.
Adjustment failure of the PF Motor
Remedies for Print Quality Troubles
Check Item
Check the paper type setting screen.
Check if the paper type setting is proper.
Check if the low print quality mode is selected.
Print the following adjustment patterns to check if the
adjustment is correctly made.
CR Direction Head Slant Adjustment
PF Direction Head Slant Adjustment
Check if the Media Feed Correction Check & Adjustment
are made properly (See P.373).
Check if it is in the specified range.
1. Check the PG of the Printhead. (See P.321)
within the specified range.
2. Check the position of the Paper Thickness Sensor.
P.369) Check if it is within the specified range.
Carry out "PF Encoder and Scale Check".
Check if the PF Scale is damaged or contaminated.
Check if the PF Scale is not skewed.
Check if the PF Encoder is installed correctly.
Measure the tension of the PF Timing Belt to check if it is
in the specified range. (See P.366)
Carry out Motor Measurement Adjustment for PF Motor
(See P.393).
1. Correct the paper type setting.
2. Select a higher print quality mode.
If it is not correctly adjusted, carry out the
following adjustments.
CR Direction Head Slant Adjustment
(See P.336) P.336)
(See P.339) PF Direction Head Slant Adjustment
P.339)
Carry out the adjustment if it is out of the specified
range. (See P.373)
Carry out the following adjustments if it is out of
Check if it is
the specified range.
PG Height Check & Adjustment
(See
Paper Thickness Sensor Position Adjustment
(See P.369)
1. Re-attach any parts with trouble
(See P.368) P.184).
2. Clean the PF Scale with ethanol if it is
contaminated.
3. Replace it if it is damaged.
P.184)
Carry out "PF Belt Adjustment" if it is out of the
specified range. (See P.366)
If the printer does not recover from the error,
replace the PF Motor
Revision A
Remedy
(See
(See
(See P.321)
(See P.183)(See
(See P.183)(See
(See P.182).
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