LG GDR-8161B Service Manual page 43

Disc-motor doesn't rotate.
LASER light up?
refer : LASER check
Focus servo OK?
refer : Focus servo check.
check wave -form:
W
IC301(12)
V
IC301(13)
U
IC301(14)
VM1
IC301(22):12V?
check waveform:
CTL1
IC301(38)
CTL2
IC301(41)
check waveform:
VHALF
IC301(25)
check waveform:
SPD
IC301(26)
Disc motor stop, immediately
after it rotated.
Check waveform :
SFG
IC201(75)
Check waveform :
SFG
IC301(24)
VH+ PG301(8) : about 5V
VH-
PG301(7) : ????V
check waveform :
IC301(16)
IC301(17)
Hn+/-
IC301(18)
IC301(19)
IC301(20)
IC301(21)
OK
OK
NG
OK
NG
OK
NG
OK
NG
OK
OK
OK
NG
NG
NG
OK
Note : When the circuit number is written, check parts and
soldering including a nearby circuit.
When two or more pin numbers are indicated by the
party, check signal-line including a nearby circuit.
Check item
• IC301 -- PG301
• PG301 connection
• Disc motor
• IC302(22) - L301 - PG701(56)
• IC301(38) -- IC201(59)
• IC301(41) -- IC201(60)
• IC201
• IC301(25) -- IC101(29)
• IC101
• IC301(26) -- IC201(56)
• IC201
• IC301
Note : When the circuit number is written, check
Check item
• IC201
• IC201(75) -- IC301(24)
• PG301(8) -- PG701(53)
• PG301(7) -- IC301(23)
• IC301
• IC301 -- PG301 -- disc motor
• Disc motor
• IC301
• R292
parts and soldering including a nearby circuit.
When two or more pin numbers are indicated
by the party, check signal-line including a
nearby circuit.
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