Service manual

TROUBLESHOOTING GUIDE 2
SM 4-45 G130/G131
4.5 TROUBLESHOOTING GUIDE 2
4.5.1 IMAGE QUALITY
Detailed Explanation
The table below shows the troubleshooting procedure for the considerable image problems.
Subject Symptom Cause Action
Symptoms not related to color
Vertical white dotted
lines
If the paper transfer bias is
excessive for the paper type
used in the low humidity
condition, vertical white
dotted lines may appear.
In the low humidity condition, the
electrical resistance of paper tends to
increase. Excessive paper transfer bias
may cause electrical leak, causing
vertical white lines.
• Check if the optional heater has been installed
in the paper tray and it is activated.
• Customize (decrease) the paper transfer
current for the related mode (SP2-301).
Vertical white lines In high temperature and
humidity conditions, vertical
white lines may appear in
halftone areas on thick paper
after multiple prints of the
same image.
In this condition, the drum sensitivity
tends to drop. Since the image transfer
efficiency differs between plain and thick
paper, sensitivity drop may cause
changes in image transfer efficiency on
thick paper, causing vertical white lines.
The drum sensitivity recovers, and this symptom
disappears after waiting for about 5 minutes after
this symptom has been observed.
Dirty lines/bands or
background on 2nd
side
The cleaning blade of the transfer belt
cleaning may be worn away or damaged
when the transfer belt cleaning unit
becomes close to its life (500KP).
Check and replace the transfer belt-cleaning unit.
Poor fusing / Fusing
offset
The type of paper selected in the printer
driver does not match the paper type
used for printing, causing the fusing
temperature not to be controlled for the
paper used.
Please instruct users to select the correct paper
type in the printer driver.