LG CM2760, Service Manual

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3-10
ELECTRICAL TROUBLESHOOTING GUIDE OF AUDIO PART
FLD display check
Refer to
Power part troubleshooting.
Check T500, L500, Q500, Q501,
D501 part circuit.
Check T500, L500, Q500, Q501,
D501 part circuit.
OK
IC500 pin3 STB,
pin2 DATA, pin1 CLK
Check data output.
Check
pin4 --> DO --> DATA input.
Replace the related part.
Replace the related part.
Replace the related part. FLD light on?
Check
CN500 pin3, 11
voltage.
NO
NO
NO
NO
NO
NO
NO
Check
the related part.
Check CN500
DATA communication
pin9 STB, pin7 DATA,
pin8 CLK.
Check VFD PCB
F+, F- both terminals:
over 3.7 V.
Check power VEE:
over -33 V.
YES
YES
YES
YES
YES
YES
YES
YES
2. FLD DISPLAY CHECK
OK