Service manual

30 July, 2001 TROUBLESHOOTING GUIDE
4-41
Action Required
Direction Area Symptom Possible Cause
Output Mode SP Mode
Procedure / Remarks
Normal Paper
600 dpi
SP5-993-
016 (Y)
SP5-993-
017 (M)
SP5-993-
018 (C)
Sub-scan Entire
image
Color shift on the
entire image, and
the amount of shift
from leading to
trailing edge is
almost the same.
SP mode setting
is not suitable for
the paper used.
Normal Paper
1200 dpi
SP5-993-
019 (Y)
SP5-993-
020 (M)
SP5-993-
021 (C)
Measure the gap between the black line and other
colors (YMC) using a magnification scope.
Convert the measured value from [µm] to [dots] with the
following formula. Then, add or subtract the calculated
dot value in the SP mode.
Correction [dots] = Measured value [µm] / 21.2 or 42.4
600 dpi mode: 1 dot = 42.4 µm
1200 dpi mode: 1 dot = 21.2 µm
If color (YMC) has shifted up in relation to black, add the
above value to the current value.
If color (YMC) has shifted down in relation to black,
subtract the above value from the current value.
Examples
• If the magenta line has shifted up in relation to black
by 40µm in 600dpi mode, add 1 to the current setting
of SP5-993-017.
Correction [dots] = +(40/42.4) = Approx. +1
• If the magenta line has shifted down in relation to
black by 70µm in 600dpi mode, subtract 2 from the
current setting of SP5-993-17.
Correction [dots] = -(70/42.4) = Approx. –2