LG 37LT75 (CHASSIS:LD74A) Service Manual ▷ View online
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(7) In the case of becomes unusual display from SCART1 mode
Is Video input
of A/V jack normal?
(J1200)
Yes
Check the input source.
No
Same as Block A
(8) In the case of becomes unusual display from SCART2 mode
Is Video input
of A/V jack normal?
(J1201)
Yes
Check the input source.
No
Same as Block A
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5. In case of no sound
(1) Symptom
1) LED is green.
2) Screen display but sound is not output
2) Screen display but sound is not output
(2) Check follow
All input (mode)
is no sound?
Is the speaker
On it men?
Set on speaker in
menu.
Is the speaker
Cable normal?
Check the Speaker
Cable
IC1300 operates
Normal?
Replace IC1300
(MSP4450)
IC1301 operates
Normal?
Replace IC1301
(STA335BW)
Replace VSC BD
Yes
No
Only HDMI is
No sound?
Yes
Download
the EDID data.
No
No
No
No
No
Only RF is
no sound?
no sound?
Yes
Check
the Tuner IN/OUT
No
Check the signal before
CXA2069 refer to circuit diagram
Only
AV/component/PC
input is no sound?
Yes
Only specific input
(except HDMI,
DTV,RF) is no
DTV,RF) is no
sound?
Yes
Is the output of
CXA2069 normal?
Check the signal after CXA2069
refer to circuit diagram
No
Replace CXA2069
No
Yes
Yes
Yes
Yes
No
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DVR Fuction Trouble Shooting Guide
1. Time shift Mode
(1) Symptom
1) Doesn't work time shift mode.
2) Can't enter to recorded list.
3) Can't record AV/RF
2) Can't enter to recorded list.
3) Can't record AV/RF
(2) Check follow
Power's operation
is normal?
Yes
Replace IC
No
No
Is time shift mode
on(in Menu)?
No
No
Yes
Are the cables
connected well?
(P1500, P1501 )
Power and Data Cable
is normal?
(P1500, P1501)
Change the power and
Data cable.
No
Yes
HDD is normal?
Change the HDD Assy.
No
Yes
Check BU9580KVT
IC(IC 1504)
Is it ok?
Yes
Replace VSC BD
Replace STI5100
IC (IC100).
No
Yes
Check STI5100 IC
(IC 100),
NEC61151F(IC1600)
NEC64015A(IC1901)
NEC64015A(IC1901)
Is it ok?
Replace STI5100,
NEC61151F
NEC64015A Is it ok?
Insert cables well.
Yes
change time shift
mode from off to on
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2. Time shift sound and Recorded video sound
(1) Symptom
1) SOUND doesn't come out.
(2) Check follow
Is it DVR Mode
(time shift or
recorded TV)?
Yes
Go on 9page in this document.
MUTE key on?
Turn off the mute key
No
Yes
Yes
No
Sound cable is OK?
Are power cables
connected well
Yes
No
No
connect speak cable
Sound is ok?
Connect power cables
/power B/D
Is Data cable(P1501)
ok?
Connect Data cable.
No
Check speakers
Are they ok?
Change the speakers
No
Yes
Yes
Yes
Check MSP(IC1300),
Audio AMP(IC1301)
Is it ok?
Change the ICs
Is it ok?
Replace VSC BD
No
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