Zenith XBS344 Series, Service Manual

Page: 54 / 159

3-60
C
No
No
No
No
No
No
Yes Yes
Yes
Yes
Yes
Yes
Yes
Yes
No
No
Laser turns on when
reading disc?
LD01 or LD02 output
properly?
Check the laser power circuit
on MT1336 and connecting to
power transistor. (Q404, Q405)
Check the related circuit on
laser power transi stor
Check the related circuit
on MT1336 RFL signal .
Collector
voltage of power
transistor is OK?
(Q404, Q405)
Check cable connection between
transistor output and pick-up head.
Proper RFL signal
on MT1336?
Proper
DMSO signal on
MT1379
Check DMSO related
circuit on MT1379.
Check the spindle control
amp circuit of motor driver.
SP+ & SP- output
properly?
Check the cable connection
between spindle and main PCBA.
Check the RFL connection
between MT1336 and MT1379.
Disc ID is correct?
Does spindle rotate?
D