LG MCV902 Service Manual page 58

1-7. READING OK CHECK #D (= "NO DISC" DISPLAY)
D
DOES
SP+ WAVEFORM
APPEAR AT (IC802 PIN11
AND PN802 PIN 5) WAVEFORM
#4 SPINDLE MOTOR
DRIVE
WAVE
YES
CHECK PN802
CONNECTOR LINE
YES
DEFECTIVE PICKUP
SPINDLE MOTOR
DOES
SPIN WAVEFORM
NO
APPEAR AT (IC802 PIN6)
WAVEFORM #4
SPINDLE DRIVE
WAVE
DEFECTIVE IC802
NO
DEFECTIVE PN802
CONNECTOR
4-7
NO
YES
DEFECTIVE IC801