LG LAC-M1600, Service Manual

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- 2-2 -
2. LCD light abnor
m
al.
YES
YES
YES
YES
YES
YES
NO NO
NO
NO
NO
NO
NO
Any Key power on.
(without DISC)
Do display LCD then light?
Check voltage in the power
supply
Power supply circuitry defective.
Q371,Q372,IC403
• Reset circuit defective.
IC901 Surrounding circuit
defective.
X101,X102,C101,
C102,C103,C104.
Q921,ZD910
PCB pattern defective.
IC906,Pin74,75,76
front PCB pattern defective.
IC901,Surrounding circuit
PCB pattern defective.
Display LCD connector
defective.
Is IC901 Com1, Com2, Com3
output waveform normal?
Is u-com IC906 Pin 74,75,76
output waveform normal?
Is u-com IC906 LCD reset
circuit normal?Pin74
Is u-com IC906 keyin
Pin19,20 5volt input?
Is u-com IC906 X1,X2 terminal
Pin11,12,14,15 input?
OSC :19.2MHz
OSC :32.768kHz