LG MCV903 Service Manual page 36

YES
Check the
PWM MODULATOR
NO
output FL:75(+) 74(-)
FR:59(+) 58(-)
SW 68(+)67(-)
YES
FL:(-)C533,
FL:(+)C516
NO
FR:()C535,
FR:(+)C560
SW:(-)C555,
SW:(+)C556
YES
Check
PN702 5PIN L-CH ,
NO
7PIN R-CH 14PIN SW
output (Check the abnormal
operation of
SIG 1V)
YES
OK
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Only for training and service purposes
P WM output waveform
FRONT :R530,
NO
518,529,532
SW :Check the output
waveform at both
terminals of
R538,534
YES
OK
Check the NO
operation condition
of IC502,504
YES
Check the
R554,553,552
output
NO
Check DA-A_MUET
(R539) LOW and
SW-MUTE (R540) LOW
operation
OK
Replace the related
part
Check the
NO
Check CN710 3PIN
IC502,504 ±12V
input power
YES
Check the
NO
Replace the related
power at both
terminals of
YES
OK
3-15
NO
Replace the See the
-12,4PIN +12V
part
LGE Internal Use Only
SMPS Ass`y