LG LPC-M155X Service Manual page 16

IF INITIAL READING IS NOT CARRIED OUT (WITH DISC)
Does disc motor Rotate?
Yes
Is HF waveform output?
IC1 pin79
Does laser light?
Yes
Is FA+ waveform output at
IC2 pin3?
focus coil drive wareform.
Yes
Is TE waveform output at
IC1 pin96?
TRACKING ERROR wareform.
Yes
Is rotation normal?
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Only for training and service purposes
Does CON1 pin5 voltage change
when Limit S/W ON/OFF.
Yes
Is IC1 pin1 voltage transmitted?
No
Yes
Check the change of
SL +, SL - Voltage.
(IC2 pin 17, 18)
Yes
No
A
No
B
No
B
Is HF signal normal without dropout?
Yes
- 3-5 -
No
No
2V
1V
2V
1.2V No
0V
0.8V
Yes
No
CON1 connector defective.
IC1 Defective.
IC2 Defective.
PICK-UP defective.
IC1 defective.
PICK-UP defective.
LGE Internal Use Only