Gestetner B070 Service Manual page 331

SC323: Excessive LD Drive Current
Definition [B]
The value of the LD driver offset current is over the allowed current (about 90 mA).
Possible Causes
• Poor LDB board harness connection
• LDB defective
• LD unit defective
SC335: Polygonal Mirror Motor Error 1
Definition [B]
The polygonal mirror motor does not reach its operating speed within 20 s after the
polygonal mirror motor turns on, or the polygonal mirror motor speed is changed.
(The XSCRDY signal does not go LOW for active.)
Possible Causes
• Poor connection between polygonal mirror motor and I/F harness
• Polygonal mirror motor, LDB, or polygon mirror motor control PCB defective
• IPU defective
Hardw are Layout
Polygon M irror
M otor Driver
Polygon mirror motor driver: Polygon mirror motor control PCB
XPMON:
PMCLK:
XSCRDY:
SM
CÓPIA NÃO CONTROLADA
XPM O N LDB
PM CLK
XSCRDY
Command that switches polygon mirror motor on/off.
BCU! IPU! LDB! Polygon mirror motor control PCB
Polygon mirror motor drive clock.
BCU! IPU! LDB! Polygon mirror motor control PCB
Polygon mirror motor ready signal.
Polygon mirror motor control PCB! LDB! IPU! BCU
4-11
CÓPIA NÃO CONTROLADA
SERVICE CALL CONDITIONS
IPU
BG AVD2 CDIC3
S erial Data Transm ission
D ata B us
A ddress B us
B070T901.WMF
B070/B071