LG 37LC7D - Page 39

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- Video doesn't display
Check J5007 Pin3C
Can you see the normal waveform?
Check the input(Pin1 or Pin8) of AV
switch(IC5003). Pin1 is for video1,Pin8 is
for video 2.
Can you see the normal waveform?
Check the output(Pin56) of AV
switch(IC5003).
Can you see the normal waveform?
Check the input(Pin1) of LPF(IC4006).
Can you see the normal waveform?
YES
YES YES
NO
J5007 may have problem. Replace this
Jack.
Check the output(Pin8) of LPF(IC4006).
Can you see the normal waveform?
YES
Check the input(PinH26) of
BCM3550(IC4006).
Measure waveform at C1010 because its
more easy to check.
Can you see the normal waveform?
YES
NO
After checking the Power of AV switch you
should decide to replace AV switch or not.
NO
After checking the Power of AV switch you
should decide to replace AV switch or not.
NO
After checking the Power of LPF you should
decide to replace LPF or not.
NO
After checking the Power of LPF you should
decide to replace LPF or not.
YEX
This board has big problem because Main
chip(BCM3550) have some troubles.
After checking thoroughly all path once again,
You should decide to replace BCM3550 or not.