LG MBD-D102X Service Manual page 29

ELECTRICAL TROUBLESHOOTING GUIDE OF DVD PART
B
Laser
turns on when
reading disc?
YES
Put disc in tray.
YES
Does SPINDLE
rotate?
YES
C
DVDLD
NO
or CDLD output
properly?
Collector
voltage of power
transistor is OK?
(Q405, Q406)
Check cable connection
between P400 and
pick-up head.
NO
Laser off
Proper
NO
SPINDLE signal
on ES8380.
SPIN+ &
SPIN- output
properly?
Check the cable
connection between
P400 and MD
3-18
NO
YES
NO
YES
NO
YES
NO
YES
Check the laser power circuit
between ES8380 and power
transistor. (Q405, Q406)
Check the related circuit of
laser power transistor.
Check the SPINDLE related
circuit on ES8380
Check the SPINDLE control
of motor driver.