LG CM1530, Service Manual

Page: 26 / 49

7. VFD DISPLAY CHECK
Check VFD display.
Check CN301 flat film wire. Replace FB307, FB702.
Replace
IC301.
Replace
IC301.
YES
NO
NO
FB729, FB730, FB731 normal? Replace FB729, FB730, FB731.
Check CN101 connect wire.
Check FB307, FB702 normal?
NO
NO
NO
YES
YES
YES
YES NO
YES
YES
Check IC103
pin36 “VFD-STB", pin37 “VFD-CLK”,
pin38 “VFD-DATA”,
signal.
Check CN101
pin7 “VFD_DATA”, pin8 “VFD_STB”,
pin9 “VFD_CLK”
signal.
Check IC103
pin62, 63 VCC 3.3 V.
Check
CON301 pin10.
IC301 normal?
Check IC301
pin25 "VCC 3.3V".
Replace IC103.
Check IC301
pin9 SCL, pin10 SDA.
NO
NO
NO
3-9
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