LG FFH-M217X Service Manual page 21

READING OK CHECK #B (= "NO DISC" DISPLAY)
B
DOES FA+ WAVEFORM APPEAR
AT
( IC503 PIN15 AND PN501 PIN16)
WAVEFORM #3
FOCUS COIL DRIVE WAVE
CHECK PN501 CONNECTOR LINE
DOES FAIN- WAVEFORM
APPEAR AT
( IC503 PIN 26)
WAVEFORM #3
FOCUS DRIVE WAVE
- 2-14 -
DEFECTIVE IC501
DEFECTIVE IC503
DEFECTIVE PN501
CONNECTOR
DEFECTIVE PICKUP
FOCUS ACTUATOR