Gestetner B147 Service Manual page 217

SC No. Item
SC 220 Synch. The front (for K&Y) or rear (for
detection signal C&M) laser synchronizing
error 1 detector board, which is used
to determine the start timing of
220-001: Y
laser writing, does not send a
220-002: M
signal while the polygon motor
220-003: C
is operating normally and the
220-004: K0
LD is on.
220-005: K1
SM
Definition Possible Cause
• Disconnection of the
cable between front
(K&Y) or rear (C&M)
synchronizing
detector board and
the LD unit
• Incorrect installation
of front (K&Y) or rear
(C&M) synchronizing
detector board (the
beam does not target
the photo detector.)
• Defective LD unit
• Defective BCU
• Defective +5VLD
circuit
Related
Troubleshooting Procedure
SCs
1. Turn the main switch off and on.
2. Check the cable connection between
front (for K&Y) or rear (for C&M)
synchronizing detector board and the
LD unit.
3. Check or reinstall the front (for K&Y)
or rear (for C&M) synchronizing
detector board.
4. Replace the front (for K&Y) or rear
(for C&M) synchronizing detector
board.
5. Replace the laser optics housing unit.
6. Replace the BCU.
7. Replace the PSU.
4-15
SC TABLE
Type
D
B147/B149/B190