LG CF-20T22Kx - Page 32

PRINTED CIRCUIT BOARD
MAIN & CPT
NO RASTER
CHECK +B
at D807 cathode
Is the voltage at pin14
& 39 of IC01 8V?
Check
FUSE of AC line
Check the voltage
of C806
Check the voltage
pin3 of IC803
Check pin33
of IC01(H-out)
Check Q402
collector waveform
Check T402
& each pin voltage
Check &replace
T402
Check &replace
IC01
Check &replace
Q402
Check &replace
T402
Check the in/out
of IC844
Check IC01
pin1 high?
Check /replace
IC801,IC803,IC804
Check /replace
Fuse,DB801
Check /replace
DB801
Normal Abnormal
Yes
Yes
Yes
Yes
No
No
No
No
No
No
No
No
No
OK
254~380V
Open
0V
Is the voltage at pin61,56
& 54 of IC01 3.3V?
Yes
Is the voltage at pin3
of IC02 5V?
Check the In/Out
of IC842
Check the voltage
at D805 or D815 
cathode
Check / Replace
F812
Check / Replace
IC01,IC02
Yes
Select correct system 
in menu
Check / Replace
IC01
Check the voltage 
at pin 6 of IC631
NO
OK
Check the waveform 
at pin 44 of IC01
Check the waveform 
at pin 4,12 of IC602
Check the voltage 
at pin 6,7 of IC602
Check the waveform
at pin 1,2,14,15 of IC602
Check the voltage 
at pin 3,13 of IC602
Check the waveform 
at pin 15,18 of IC631
Check/Replace
F811,D824
Check/Replace 
Q621,IC603
Check/Replace
IC602
OK
OK
OK
OK
OK
NO
NO
AV STEREO
NO
NO
NO SOUND / PICTURE OK
Select correct system 
in menu
Check the waveform 
at pin 35 of IC501
Check the waveform 
at pin 4 of IC651
Check the waveform 
at pin 44 of IC01
Check the waveform 
at pin 4 of IC601
Check the voltage 
at pin 5 of IC601
Check the waveform 
at pin 1 of IC601
Check/Replace Q621
Check/Replace 
FR803,D804
Check/Replace IC601
OK
OK
OK
Check the waveform 
at pin 2,7 of IC651
OK
NO
NO
Check / Replace
IC651
Check/Replace 
IC01
Check the waveform
at pin28 IC01
NO
NO
MONO
Select correct system 
in menu
Check / Replace
TU101
Check the voltage 
at pin 16,33,46 of IC661
NO
OK
Check the waveform 
at pin 16 of TU101
Check the waveform 
at pin 4,12 of IC602
Check the voltage 
at pin 6,7 of IC602
Check the waveform
at pin 1,2,14,15 of IC602
Check the voltage 
at pin 3,13 of IC602
Check the waveform 
at pin 24,25 of IC661
Check/Replace
F811,D824
Check/Replace 
Q621,IC603
Check/Replace
Q671,Q672
OK
OK
OK
OK
OK
NO
NO
Check the voltage
at pin1 of IC131
RF STEREO
NO
NO
NO
NO
NO
NO
NO
NO
OK
Check/Replace
IC131,IC661
NO PICTURE / NO SONUD
Is any OSD displayed?
Check receiving system in MENU
& excute Auto-program.
OK
OK
NO
Check/ Replace
IC01

No
Go to
NO SOUND /
PICTURE OK
Does the Auto-program
operate properly.
Store in manual-program MENU
Check 5V, 33V & IIC Bus Line
of TUNER
Is the CVBS signal OK.
( IC01 pin40 )
Check R,G,B signal
at IC501 pin51,52,53
Check
5V, 33V &
IIC Bus Line
OK
NO
NO
OK
OK
Check / Replace
IC01,TUNER
NO
OK
Check / Replace
CPT Board component
Check
CVBS singal Line
& IC01
Check IK

signal at IC01 pin50
(similar to CVBS)
Check IC01 pin50,51,52,53
(IK,R,G,B)
OK
NO
NO RASTER / SOUND OK
Check the
Heater voltage of CPT
(6 ~ 6.5Vrms)
Check
FR404,FR902,P302
Check
FBT T401
Check the
Heater pulse of FBT
T401
Check
Ik Current of
IC01,pin50
Not OK
OK Not OK
Check/Replace
CPT Board
Components
Check
IC01,ZD901
IC901,P902,P541
OK Not OK
OK
Check
HV, Screen voltage of
CPT
Check
FBT T401
Not OK
TROUBLESHOOTING
COMPONENT LOCATION GUIDE
WIRING DIAGRAM
"D" POINT : SPEAKER(L) LEAD & D-COIL
1. CONNECTOR LEAD
JW2
P602
SPK(R)
P01A
P601
SPK(L)
P541
SPK(R)
4
" C "
P302
MAIN PWB
POINT
1
P802
JW1
" A "
P902
1
P301
P801
BN
BL
POWER CORD
POINT
" D "
SPK(L)
3
CPT PWB
POINT
" B "
"C" POINT : D-COIL HOLDER SPEAKER(L)
JW1, FOCUS & SCREEN LEAD
P802 D-COIL HOLDER 1
TWISTER HOLDER
"B" POINT : TWISTER HOLDER
"A" POINT : P541, P301, P302, CPT EARTH,
,JW2
LEAD
C01.........B4
C02.........B4
C03.........B3
C04.........B4
C05.........B4
C06 ........C4
C07.........B3
C09 ........C4
C10.........B3
C11.........B4
C16.........F1
C21.........E1
C51.........B4
C101.......A5
C102.......A5
C103.......B5
C104.......B5
C105.......B5
C106.......A5
C107.......A5
C108.......A5
C109.......A4
C110.......B5
C111.......B5
C112.......B5
C113.......A4
C114.......A4
C121.......A4
C123.......A4
C131.......A4
C132.......A4
C201 ......C5
C202.......B5
C203 ......C5
C204.......B5
C205 ......C5
C206 ......D5
C207 ......D5
C208 ......D5
C209 ......D5
C210.......E5
C211 ......D5
C212 ......D5
C221 ......D5
C222 ......D5
C223 ......D5
C224.......E5
C251 ......D1
C253 ......C1
C255 ......C1
C256.......B1
C257.......B1
C258 ......C1
C259 ......C1
C260 ......C1
C261 ......C1
C262 ......C1
C301.......F4
C302.......E4
C303.......E4
C304.......E4
C305.......E4
C306.......E4
C307.......F4
C401 ......G4
C402.......F3
C403 ......G4
C404 ......G4
C405 ......G4
C441 ......G3
C442.......E5
C443.......E5
C444 ......G5
C445.......E5
C446.......E5
C449.......F5
C450 ......G5
C452 ......G3
C453.......E4
C457 ......G5
C501 ......C4
C502.......B5
C503 ......C5
C504 ......C4
C505 ......C4
C506 ......C5
C507 ......C5
C508 ......C3
C509 ......C4
C510 ......C4
C511 ......C5
C512 ......D4
C513 ......D4
C514 ......C4
C515 ......C5
C516 ......C5
C517 ......C4
C518 ......D4
C519 ......C4
C524 ......D4
C529 ......D4
C530 ......C4
C531 ......C4
C532.......B2
C534 ......C4
C535 ......C4
C536 ......C4
C538 ......C3
C540 ......C4
C541 ......C4
C542 ......C4
C543 ......C3
C544 ......C3
C545 ......C3
C546 ......C3
C548 ......D4
C549 ......C4
C551 ......D4
C552 ......D4
C553 ......D3
C561 ......C4
C573.......E5
C574.......E5
C593 ......C3
C594 ......C4
C595 ......C1
C601.......B3
C602.......B2
C603.......B2
C604.......B3
C605.......B2
C606.......A2
C607.......B3
C611.......B3
C612.......B3
C621.......A2
C622.......A3
C623.......A3
C624.......B2
C625.......A2
C626.......A2
C631 ......D1
C632 ......D2
C633 ......D1
C634 ......C1
C635 ......D1
C636 ......C1
C637 ......C1
C638 ......C1
C639 ......C2
C640 ......C2
C641 ......C2
C642 ......D2
C643 ......D2
C644 ......D1
C645 ......D2
C646 ......D1
C653 ......D2
C654 ......D3
C655 ......C1
C661 ......C3
C662 ......C3
C663 ......C3
C664 ......C3
C665 ......D3
C666 ......D2
C667 ......D3
C668 ......D3
C669 ......D3
C670 ......D2
C671 ......D2
C672 ......D2
C673 ......D2
C674 ......D2
C675 ......C2
C676 ......D2
C677 ......D2
C678 ......C2
C679 ......C2
C680 ......C2
C681 ......C2
C682 ......C2
C683 ......C2
C684 ......C2
C685 ......C2
C686 ......C2
C687 ......C2
C688 ......C2
C689 ......C2
C690 ......C2
C801.......F2
C802.......F2
C803 ......G2
C804.......F3
C806.......F2
C807.......F2
C808 ......G2
C809 ......G1
C811 ......G3
C812.......E2
C813 ......D2
C814 ......D1
C815.......E3
C816.......E3
C817.......E3
C818 ......D3
C819.......E4
C820.......E3
C821.......E2
C822.......E3
C823 ......G3
C824 ......D1
C825 ......G3
C826 ......D1
C828 ......D2
C829 ......G2
C830.......E2
C831.......E3
C832.......F3
C833.......F4
C834.......F4
C835 ......D1
C841 ......D3
C901.......B1
C902.......A1
C903.......A2
C904.......B2
C905.......A1
C906.......B1
D101.......B5
D102 ......C5
D301.......E4
D302.......E4
D401 ......G4
D403.......F4
D441 ......G4
D442.......E5
D443.......E5
D444 ......G5
D501.......B3
D571.......F5
D602.......B3
D621.......A3
D801.......E2
D802.......F3
D803.......F3
D804.......E2
D805.......E2
D806.......F2
D807.......E4
D808.......E3
D809 ......D1
D810.......E1
D811 ......D1
D812.......E1
D813 ......D2
D814.......E2
D901.......A1
D902.......A1
D903.......A1
D904.......B2
DB801....G2
F802.......G2
F811 .......E2
F812 .......E2
F801A ....G2
F801B ....G1
FB801.....F2
FB802.....F2
FB803.....E3
FR441 ....E5
FR442 ....E5
FR443 ....E5
FR802 ....E3
FR803 ....E2
FR901 ....B1
HIC01.....D3
IC01........B4
IC02........B3
IC03........B4
IC130......A4
IC301......E4
IC591 .....C3
IC601 .....D1
IC602......A3
IC603......B3
IC621......A3
IC631 .....D1
IC661 .....C2
IC662 .....C2
IC801......F3
IC802......F3
IC803 .....G2
IC804......F3
IC842 .....D2
IC844......E3
IC901......A1
L01 .........E1
L04 .........B4
L05 .........B3
L10 .........B3
L102 .......B5
L201 .......C5
L202 .......B5
L203 .......C5
L204 .......D5
L205 .......D5
L210 .......E5
L251 .......C1
L252 .......C1
L253 .......B1
L254 .......B1
L255 .......C1
L260 .......C1
L401 .......F4
L402 .......F4
L501 .......C5
L502 .......D4
L503 .......D4
L506 .......D4
L551 .......D3
L552 .......D3
L553 .......D4
L601 .......D2
L611 .......D3
L621 .......D3
L631 .......D2
L661 .......B2
L662 .......D3
L663 .......C2
L801 .......E4
L802 .......E3
LD01.......F1
P102.......B5
P302.......E5
P541.......C3
P601.......B2
P602.......B2
P701.......B2
P901.......A2
P902.......B1
P903.......B2
P01A ......A4
P02A ......D1
P03A ......D1
P05A ......C1
P06A ......B2
P301A.....F4
P301B.....F4
P301C ....F4
P301D....G4
P801A ....G1
P801B ....G1
P802A.....F1
P802B.....F1
PA01.......F1
PJ201.....C5
PJ202.....C1
Q01 ........E1
Q11 ........B5
Q101 ......B5
Q102 ......B5
Q103 ......C5
Q123 ......A4
Q211 ......D4
Q212 ......D4
Q213 ......E5
Q214 ......D5
Q215 ......E4
Q216 ......E5
Q301 ......E4
Q402 ......G4
Q442 ......G3
Q443 ......G5
Q551 ......C3
Q552 ......D4
Q553 ......D3
Q554 ......D3
Q555 ......C3
Q571 ......E5
Q621 ......A3
Q651 ......D5
Q652 ......D5
Q653 ......D4
Q671 ......D3
Q672 ......D3
Q801 ......E4
Q802 ......E4
Q803 ......E2
Q804.......F4
Q805 ......E4
Q806 ......E4
R01.........B4
R02.........B4
R03.........B4
R04.........B4
R05.........B4
R06.........B3
R07.........B3
R08.........B4
R09.........B4
R10.........B4
R11.........B4
R12.........B4
R13.........B4
R14.........B5
R15.........B5
R16.........B4
R17.........B4
R18.........B5
R19.........B4
R20.........A4
R21.........E1
R22.........E1
R23.........E1
R25.........E1
R26 ........D1
R27 ........D1
R28.........B5
R29 ........D1
R30.........B5
R31.........B5
R32.........E1
R41.........A4
R51.........B4
R52.........B4
R101.......B5
R102.......B5
R103.......B5
R105.......B5
R106.......B5
R107.......A5
R108.......B5
R109.......B5
R110.......B5
R111.......B5
R112.......B5
R113.......B5
R114.......B5
R115 ......C5
R116 ......C5
R117 ......C5
R118 ......C5
R121.......A4
R122.......A4
R123.......A5
R124.......A5
R132.......A4
R133.......A4
R134.......A4
R201 ......C5
R204 ......C5
R205 ......C5
R206 ......C5
R207 ......C5
R208.......E5
R212 ......D5
R213 ......D5
R214.......E5
R215.......E5
R216 ......D5
R217 ......D5
R218 ......D5
R219 ......D5
R220 ......D5
R221 ......D5
R222 ......D5
R223 ......D5
R224 ......D5
R225 ......D5
R226.......E5
R227 ......D5
R228 ......D5
R251 ......C1
R254.......B2
R255.......B2
R301.......E4
R302.......E4
R304.......E4
R305.......E4
R306.......F4
R307.......E4
R308.......E4
R310 ......D4
R311.......E4
R312.......E4
R313.......E4
R401.......F4
R402.......F4
R442 ......G3
R443.......F3
R444 ......G4
R446.......F5
R447.......E5
R448 ......G5
R450.......E5
R451.......F3
R453.......F5
R454 ......G3
R455.......E5
R456.......F5
R501 ......C5
R502 ......D3
R503 ......C3
R504 ......C4
R505 ......C5
R506 ......D5
R518 ......D4
R521 ......D4
R522 ......D4
R523 ......D4
R524 ......D4
R525 ......D4
R526 ......C4
R537 ......C3
R538 ......C3
R539 ......C3
R540 ......C3
R541 ......C3
R542 ......C3
R544 ......D4
R545 ......C3
R546 ......C3
R547 ......C3
R548 ......C3
R551 ......C4
R552 ......C4
R553 ......C4
R554 ......D4
R555 ......D4
R556 ......D4
R557 ......D3
R558 ......C4
R559 ......C3
R560 ......D4
R561 ......D4
R572.......E5
R573.......E5
R601.......B3
R602.......B3
R603.......B3
R604.......B2
R606.......B2
R608.......B2
R609.......B2
R610 ......C3
R611 ......C3
R621.......A3
R622.......A3
R623.......A3
R624.......A3
R625.......A3
R626.......A3
R627.......A3
R628.......A2
R631 ......C1
R632 ......C2
R633 ......C2
R634 ......C2
R651 ......D5
R652 ......D4
R653.......E5
R654 ......D5
R655 ......D5
R656 ......D5
R657 ......D4
R662.......B2
R663.......B2
R664 ......C3
R665 ......D3
R666 ......D3
R667 ......D2
R668 ......D2
R669 ......D2
R670 ......C2
R671 ......C2
R672 ......C3
R801.......F3
R802.......F3
R803 ......G2
R804 ......G3
R805 ......G2
R806.......F3
R807 ......D2
R808.......E4
R809 ......G2
R810.......E2
R811 ......D1
R812 ......G3
R813.......E3
R814.......E3
R815.......F3
R816.......F3
R819.......F4
R820.......F4
R822.......F4
R823.......E4
R824.......E4
R901.......B1
R902.......B1
R903.......B1
R904.......B1
R905.......B1
R906.......A1
R907.......A1
R908.......A1
R909.......A1
R910.......A1
R911.......A2
R912.......B1
RC801 ....F2
RL801.....E2
SG901 ....A1
SG902 ....A1
SG903 ....A2
SG904 ....A2
SW01 .....D1
SW02 .....D1
SW03 .....D1
SW04 .....D1
SW05 .....E1
SW06 .....E1
SW801 ...G1
T101 .......B5
T401 .......F5
T402.......G4
T551.......D3
T552.......D3
T553.......D3
T801 .......F1
T802 .......F3
T803 .......E1
TH801 ....E1
TH802.....F2
TU101 ....B5
VD801....G1
X01.........B4
X661.......C2
Z102.......C5
Z551.......D4
ZD01 ......A4
ZD101 ....A5
ZD441.....F4
ZD442 ....E5
ZD443 ....E4
ZD447 ....G5
ZD501 ....C3
ZD601 ....B3
ZD801 ....E4
ZD901 ....B1
ZD902 ....B1
ZD903 ....B1
ZD904 ....B1
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