3-4
FLD display check
YES
YES
Replace the related part
Check power
of each PIN
NO
NO
YES
YES
OK
Replace the related part
Check the
related part
NO
YES
Replace the related part
FLD light on?
Check the
related part
NO
YES
YES
OK
Refer to SMPS
Troubleshooting
4. FLD DISPLAY CHECK
YES
YES
Check P7904
1,2,3 power.
NO
Check P7302 assembly
NO
When 5V fails, check
D301SR35 input and
output power
YES
Check
P7302 connection
condition and power F1+,
F2- both terminals: over 3.7V
Check power VKK: over
-28V Check 24
PIN:5.6V
YES
YES
YES
YES
OK
OK
76PIN--> DO
--> DATA input
NO
IC100
75PIN - > STB
78PIN - > 1PIN CLK
Check Data output.
Check IC100
--> IC301 DATA
communication
PIN PIN
75PIN-->3PIN STB
76PIN-->2PIN DO
78PIN-->1PIN
CLK
Check IC301
PT6324 power
50PIN VKK: -28V
9.51PIN +5V
F1+,F2- both
terminals: over 3.7V
Check power VKK: over -28V.
ELECTRICAL TROUBLESHOOTING GUIDE OF AUDIO PART
Copyright © 2007 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only