Samsung SC-148B Service Manual page 30

No spindle motor rotation
Insert disc.
Y
Focus lock?
Y
The below waveform is
inputted in IC502 22Pin?
Spindle motor kick signal
Y
IC502 4Pin, 29pin is 12V?
Y
IC502 5Pin is 5V?
Y
The below waveform is inputted in IC502
Y
Y
IC502 5Pin is 5V?
Y
Spindle Motor FPC is connected?
Y
Replace spindle Motor
N
Refer to 'No focus lock'
Refer to 'No focus lock'
N
N
Check IC301 38pin soldering
Check R323 soldering
N
Check C519 soldering
Check IC502 23pin soldering
N
N
Replace IC502
23