Gestetner B147 Service Manual page 271

As explained on the previous page, there are several types of color shift problem. The following table shows the symptoms,
factors, action required, and the page to see for details.
Symptom
1 Color shift on entire image in
main-scan and/or sub-scan
directions
2 Color shifts only at the
leading edge area
(sometimes causing shock
jitter, magenta or cyan lines)
3 Color shifts only at the trailing
edge area
4 Color shifts between the front
and rear sides
B147/B149/B190
Factors
• Line position adjustment does not
function properly.
• Transfer belt unit has just been
replaced.
Registration roller speed is not
appropriate.
Fusing belt/roller speed is not
appropriate.
Paper skew on transfer belt
• Side fences are not properly set.
• Pressure between the paper
attraction roller and transfer belt is
not even at the front and rear
sides.
Action Required
• Check the result of the line position
adjustment (SP5-993-007) and solve the
problem if an error was detected.
• Check which color lines are shifted from
black line and adjust the SP modes for
registration and magnification.
Adjust the color development motor speed
(SP1-004-4, 5, and SP1-005-003) depending
on the process speed.
Adjust the black development motor speed
(SP1-004-001, 002, and 007, or "Fuser
Adjust" in the User Program mode) depending
on the process speed.
Reposition the side fences.
Reposition the paper attraction roller unit.
4-69
TROUBLESHOOTING GUIDE
Refer to #
Page 4-4
Main-scan
Page 4-56/57
Sub-scan
Page 4-54/55
Transfer Unit
Page 4-60
Page 4-54
Page 4-54
Page 4-57
SM