LG DKC880 Manual page 16

C
Laser turns on when
reading disc?
YES
Put disc in?
YES
Disc ID is correct?
YES
Does spindle rotate?
YES
D
LD01 or LD02 output
NO
properly?
Collector voltage of
power transistor is OK?
Check cable connection
between transistor ouput and
pick-up head.
NO
Laser off
Proper RFL signal
NO
on MT1389E?
Check LDO1 & LDO2 signal
Proper DMSO signal on
NO
MT1389E.
SP+ & SP- output properly?
Check the cable connection
between spindle and main PCBA.
3-7
NO
YES
NO
YES
NO
YES
NO
YES
NO
YES
Check the laser power circuit
on MT1389E and connecting
to power transistor.
Check the related circuit on
laser power transistor.
Check the related circuit
on MT1389E RFL signal.
Check DMSO related
circuit on MT1389E.
Check the spindle control
amp circuit of motor driver.