LG CM2760 Service Manual page 34

ELECTRICAL TROUBLESHOOTING GUIDE OF CD PART
4-1. READING OK CHECK #A (= "NO DISC" DISPLAY)
#A
Does SL+
waveform appear at (IC101 pin11
& IC100 pin15) waveform#2
sled motor Wave.
YES
Check
CN101 line.
YES
Defective pick-up sled motor.
4-2. READING OK CHECK #B (= "NO DISC" DISPLAY)
#B
Does F+
waveform appear at (IC101 pin14
& IC100 pin13) waveform#3
focus coil drive wave.
YES
Check connector
CN100 line.
YES
Defective
pick-up focus actuator.
Does
NO
SLIN waveform
appear at (IC100 pin4)
waveform #2 sled drive
wave
Defective IC101.
NO
Defective CN101.
Does
NO
VINFC waveform
appear at (IC100 pin1) waveform
#3 focus drive
wave.
Defective IC101.
NO
Defective CN100.
3-19
NO
YES
NO
YES
Defective IC100.
Defective IC100.