Trouble Shooting - LG 21FG1AL Service Manual

1. TV FUNCTIONAL
11100 TUNER / IF
12500 VIDEO/MICOM
13100
SMPS
18200
Secondary
SMPS Primary
18100
2. TU / IF SECTION
11100 TUNER
11101
TUNER INPUT SECTION
5V(ZD102,C108,C106)
30V(C103,C107,ZD103,R150)
TUNER Not Working
TU SEARCH Problem
TUNING Problem
3. VIDEO PROCESSING
12500 VIDEO/MICOM
11100
TUNER
R154,C101,Z111
NO CH. SEARCH
NO PICTURE
NO SOUND.
12502
REAR A/V DVD
AUDIO L/R L IN: L221,C215
R IN: L222,C222
VIDEO IN: L225,R226
DVD-Y,Pb,Pr IN: C210,C211,C212
DVD-R IN: L221,C215
DVD-L IN: L222,C222
AUDIO/VIDEO No I/P, O/P
Copyright©2008 LG Electronics.Inc. All right reserved.
Only for training and service purposes.

TROUBLE SHOOTING

14400 HORZ. DEFL
SOUND VERT. DEFL
15300
16100 CPT
11100
2 7 8 10
3
TUNER/IF
6
11
(TU101)
9
4
5 1
11102
CONTROL SECTION
SDA(R514)
SCL(R516)
TUNER Not Working
TU SEARCH Problem
TU Weak Picture Signal
12500
61 ~ 64
31,32 1 CHIP IC (IC501)
1~13
12
12503
OSC SECTION (4.43MHz)
X501,
R537
SET Maneuver
defectiveness
Clock Error
OSD Not Working
MENU Picture Error
11103
MOD. CONTROL SECTION
AGC(C110,R151,J108,R109
,R154,R108)
TV system Detection Problem
TV MODE Weak Picture Signal
12511
R/C RECEIVER
PA01,R82,C30,C28,
In case of influx NOISE
R/C is not operate
12510
LED O/P Section
LD11,R58,R60,R72,Q10
12509
KEY I/P Section
SW11~SW16
R16,R17,R18,R19,R20,R66
KEY Error
35,36,40
50~64
46~49
LV762XX
17~22
04,09,35,4
41 9,62
12504
RESET SECTION
R22,C15
SET Maneuver
defectiveness
MENU Picture Error
SET LATCH-UP
- 14 -
11104
VIDEO/SOUND BUFFER
IF(Z111,C101,R100)
No Video Signal No Sound Signal
Video S/N Problem Sound S/N Problem
Video Noise· No Sound Noise
12508
SOUND Section
R501,R504,C502,C506,C507
R622,R621
NO SOUND
12507
R/G/B DRIVE Section
R505~R510, C510
C510,C511,R515
NO PICTURE
12506
DEFLECTION SECTION
• R404,R512,R532,C512,C513
• C515,C516,C517,C523,C544
Deflection Problem
Vertical/Horizontal Line
12505
POWER SUPPLY SECTION
POWER
ST-5V(C521,R528)
RGB 9V(C510,C511,R515)
IF VCC(C528,C526,L528,C547)
VCC(C518,L503)
SET Maneuver defectiveness
KEY Not Working No Sound
LGE Internal Use Only