LG 50PG20 Series User manual

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Copyright©2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
TROUBLE SHOOTING GUIDE

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Copyright©2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
TROUBLE SHOOTING GUIDE
Power-Up Boot Fail Trouble Shooting
Check P701 All
Voltage Level (16V, 5V)
Check Power connector
OK ? Replace Power board
Y
NY
Check IC706 #2 Pin
Voltage Level 2.6V
Replace IC706 &
Recheck
Y
N
Check X100 Clock
12MHz Replace 100
Y
N
Replace IC105 Flash Memory
Check Q706 Output
Voltage Level (5V) Replace Q801
N
Y

- 13 -
Copyright©2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
TROUBLE SHOOTING GUIDE

- 14 -
Copyright©2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
TROUBLE SHOOTING GUIDE
No OSD Trouble Shooting
Check P302
#33(TXAC-) , #32(TXAC+) ,
#17(TXBC-) , #16(TXBC+)
Maybe Mstar has problems
Check LVDS Cable
Check PDP Module
Control board
Refer to Module CAS
Y
N
Y
Replace Cable
N
Y
Check PDPVs,Va Voltage
Module 5V Replace Power
N
Check P701Disp_EN,
VaVs ON, 5V_MNT Check GPIO Path
N
Y

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Copyright©2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
TROUBLE SHOOTING GUIDE
No OSD Trouble Shooting (Module Power Sequence)
Normal Display
Vcc
(5V)
Va
Vs
DISPEN
TVaR
TVsR
TOn
TVaF
TVsF
TOff
☞1)
Power_on
3 Sec
Power_off
3 Sec
Min
100ms
Min.
2Frame (Recommend: 2 sec)
msec50090Falling Time of Vs (90% to 10%)TVsF
msec2000600
Time interval between 90% of Vcc and 90% of Vs
when Power On
Ton +
TVsR
msec800100Rising Time of Vs (10% to 90%)TVsR
msec30050Falling Time of Va (90% to 10%)TVaF
msec30010Rising Time of Va (10% to 90%)TVaR
msec-20
Time interval between 10% of Vs and 90% of Vcc
when Power Off
TOff
msec-500
Time interval between 90% of Vcc and 10% of Vs
when Power On
TOn
unitMax.Min.DescriptionSymbol

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Copyright©2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
TROUBLE SHOOTING GUIDE
Module Control Trouble Shooting
Check the PDP Module Control
Board Replace Module Control Board
N
Y
Check the IIC To II C Test
- Debug Menu IIC Test
Remove R330, R334
Check each IC sharing
IIC channel
N
Check P302 SCL,SDA line SCL,SDA
line R330, R334 Check Signal
N
Y
SCL (continue)
SDA (continue)
ACK
By Slave
9 1
D0
D7
9
ACK
By Slave
Command Data
for Addr Stop
By Master
D6
SCL 8
SDA 00
111 A7W
Start
By
Master
Chip ID Address Byte
(0x1C) ACK
By Slave
0
19 1
A6 A1 A0
Command Address
Addr=A[7:0]
0
Write
only
Master : Image Board
Slave :PDP Module

- 17 -
Copyright©2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
TROUBLE SHOOTING GUIDE

- 18 -
Copyright©2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
TROUBLE SHOOTING GUIDE
Digital TV Video Trouble Shooting
Check RF Cable
Check TP Clock, Data, Sync
R440, R441, R442 Maybe Tuner(TU400) has problems
Check Mstar LVDS output
#33(TXAC-) , #32(TXAC+) ,
#17(TXBC-) , #16(TXBC+)
Y
N
Check Tuner 5V Power
IC703 #5 Pin Replace IC703
Y
N
Y
Maybe Mstar(IC100) has problems
N
Y
Check LD400 color Bad Tuner. Replace Tuner.
None
Yellow --> none
Check Demodulator Input Clock
X400 (25MHz) Replace it
N
Y
Check PDP Module
Control board
Refer to Module CAS

- 19 -
Copyright©2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
TROUBLE SHOOTING GUIDE

- 20 -
Copyright©2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
TROUBLE SHOOTING GUIDE
Analog TV Video Trouble Shooting
Check RF Cable
Check CVBS signal
TU400 #16 Pin Maybe Tuner(TU400) has problems
Check CVBS signal
C112
Y
N
Check Tuner 5V Power
IC703 #5 Pin Replace it
Y
N
Y
Replace it
N
Y
Maybe Mstar(IC100) has problems

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Copyright©2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
TROUBLE SHOOTING GUIDE

- 22 -
Copyright©2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
TROUBLE SHOOTING GUIDE
Component Video Trouble Shooting
Check signal format
Is it supported?
Check signal
C833, C834, C835, C838, C839, C840 Replace it.
Check signal IC601 output
R631, R632, R633
Y
Y
N
Check JK602 / JK603 Replace connector
Y
N
Y
Replace it
N
Maybe Mstar(IC100) has problems
Y
Check Component Cable

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Copyright©2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
TROUBLE SHOOTING GUIDE

- 24 -
Copyright©2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
TROUBLE SHOOTING GUIDE
RGB Video Trouble Shooting
Check signal format
Is it supported?
Check signal,Hsync, Vsync
R673, R674 Replace it.
Check signal
R678, R679, R680
Y
Y
N
Check JK607 Replace connector
Y
N
Y
Replace it.
N
Maybe Mstar(IC100) has problems
Y
Check Signal
C116, C124, C126 Replace it
N
Check RGB Cable
Y

- 25 -
Copyright©2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
TROUBLE SHOOTING GUIDE

- 26 -
Copyright©2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
TROUBLE SHOOTING GUIDE
AV Video Trouble Shooting
Check signal format
Is it supported?
Check signal
C948 (Composite), C991 / C992 (S-Video) (Rear)
C949 (Composite)
Replace it.
Check signal
C111 (Composite), C109 / C110 (S-Video) (Rear)
C174 (Composite) (Side)
Y
N
Check JK601 (Rear)
Check JK604 (Side) Replace connector
Y
N
Y
Replace it
N
Maybe Mstar(IC100) has problems
Y
Check AV Cable / S-Video Cable
Y

- 27 -
Copyright©2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
TROUBLE SHOOTING GUIDE

- 28 -
Copyright©2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
TROUBLE SHOOTING GUIDE
HDMI Video Trouble Shooting
Check signal format
Is it supported?
Y
Check J801 / J802 / J803 Replace connector
Y
N
Y
Check HDMI Cable
Check EDID NVRAM
(IC801, 802, 804)
Power & I2C Signal (#5, #6)
Replace it or re-download
Y
N
Check HDCP Key NVRAM (IC102)
Power & I2C Signal (#5, #6) Replace it
Y
N
Check IC803 Out Voltage Level
3.3V Replace it
Y
N
Check L802 Voltage Level 3.3V Replace it
Y
N
Check IC803 Clock Signal
#26, #27 Replace it
Y
NMaybe Mstar(IC100) has problems

- 29 -
Copyright©2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
TROUBLE SHOOTING GUIDE

- 30 -
Copyright©2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
TROUBLE SHOOTING GUIDE
All Source Audio Trouble Shooting
Make sure you cant hear any audio
Check Signal
L919, L920 Replace it.
Check Signal
L509, L510, L511, L512
Y
N
Check IC502 Power 16V, 3.3V, 1.8V Re-check
Y
N
Y
Replace it
N
Check Connector
JK501
Y
Check Mstar I2S Output
R1035, R1037, R1038
Y
Replace it.
N
Replace connector
N
Check speaker
Y
Replace speaker
N
Maybe NTP3000A has problems. Replace it
Y