Uneven Pitch And Jitter Image - Toshiba e-STUDIO2330C Service Manual

26.5.2

Uneven pitch and jitter image

<Symptoms>
Original mode
All modes Occurs cyclically at right
angles to paper feeding
direction
Cause/Section Step
1 Test printing (A3/LD)
Drum 2 Are there uneven pitches of approx.
94 mm?
3 Is there any damage on the drum
surface?
Drum drive 4 Is there any dent, damage or
deformation on the gears of the drum
drive unit?
Drum rotation 5 Check the drum motor operation in
abnormality the test mode (03) to see if there is
any rotation abnormality of the drum.
Developer 6 Are there uneven pitches of approx.
sleeve 28 mm?
Inadequate 7 Check the value set for drum motor
drum motor rotation speed. (Is the value
rotation speed significantly different from the default
value?)
Drum coupling 8 Loose coupling, damage,
deformation
Transfer belt 9 Deformation or damage of the
transfer belt
10 Stain or damage of the drive roller
11 Large driving load due to the peeling
of the cleaning blade
Transfer belt 12 Are there uneven pitches of approx.
drive 1.5 mm?
13 Is the gap between the TBU drive
gears adjusted properly?
14 Is there any dent, damage or
deformation on the TBU drive gears?
Laser optical 15 Check the halftone pattern to see if
unit there are uneven pitches of approx.
0.3 mm, 0.8 mm, 1.1 mm, 1.5 mm
each in the whole image.
e-STUDIO2330C/2820C/2830C/3520C/3530C/4520C
ERROR CODE AND TROUBLESHOOTING
Location
Uneven pitch
Check Item
26 - 124
Phenomena
Feeding
direction
Fig. 26-1
Measure
Output the built-in halftone
and grid patterns.
Replace the drum.
Clean or replace the
drum.
Replace the gears of the
drum drive unit.
Reconnect the
connectors.
Replace the harnesses.
Replace the LGC board.
Replace the drum motor.
Replace the developer
sleeve.
Reset drum motor speed
to 128.
Replace the couplings.
Replace the transfer belt.
Clean or replace the drive
roller.
Replace the cleaning
blade.
Adjust the gap between
the TBU drive gears.
(Ref. Ch.14.7.2)
Replace the TBU drive
gears.
Replace the laser optical
unit.
© 2008, 2009 TOSHIBA TEC CORPORATION All rights reserved
Remark
For the following
checks
Check the halftone
pattern.
(Uneven pitch:
approx. 90 mm)
Check the halftone
pattern.
(Uneven pitch:
approx. 90 mm)
Check the halftone
pattern.
(Uneven pitch:
approx. 0.3 mm,
0.8 mm, 1.1 mm,
1.5 mm)