Service manual

SC TABLE
G130/G131 4-12 SM
SC No. Item Definition Possible Cause
Related
SCs
Troubleshooting Procedure Type
SC 221 Synch.
detection signal
error 2
221-001: Y
221-002: M
221-003: C
221-004: K
Main scan length detection is
not correctly completed ten
consecutive times.
The front (for C&M) or rear (for
K&Y) laser synchronizing
detector boards are used for
the main scan length detection,
which automatically corrects
the main-scan magnification.
• Damaged or
disconnected cable
between front (C&M)
or rear (K&Y) laser
synchronizing detector
board and the LD unit
• Incorrect installation of
front (C&M) or rear
(K&Y) synchronizing
detector board (the
beam does not target
the photo detector.)
• Defective front (C&M)
or rear (K&Y)
synchronizing detector
board
• Defective LD unit
SC220-
1 to 4
After doing one of the following, print
ten jobs or more to see if the same SC
code shows:
1. Turn the main switch off and on.
2. Check or replace the cable-
connecting front (for C&M) or rear
(for K&Y) synchronizing detector
board and the LD unit.
3. Check or reinstall the front (for C&M)
or rear (for K&Y) synchronizing
detector board.
4. Replace the front (for C&M) or rear
(for K&Y) synchronizing detector
board.
5. Replace the laser optics-housing
unit.
6. Replace the BCU.
Do the following as a temporary
measure if you cannot replace the
synch. detector board:
• Disable main scan length detection
(SP 2-919-001)
D