DOWNLOAD LG 42PG20-UA (CHASSIS:PU84A) Service Manual ↓ Size: 11.75 MB | Pages: 49 in PDF or view online for FREE

Model
42PG20-UA (CHASSIS:PU84A)
Pages
49
Size
11.75 MB
Type
PDF
Document
Service Manual
Brand
Device
TV / Plasma
File
42pg20-ua-chassis-pu84a.pdf
Date

LG 42PG20-UA (CHASSIS:PU84A) Service Manual ▷ View online

- 14 -
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 PDP Vs,Va Voltage
Module 5V
Replace Power
N
Check P701 Disp_EN,
VaVs ON, 5V_MNT
Check GPIO Path
N
Y
- 15 -
TROUBLE SHOOTING GUIDE
No OSD Trouble Shooting (Module Power Sequence)
Normal Display
Vcc
(5V)
Va
Vs
DISPEN
T
VaR
T
VsR
T
On
T
VaF
T
VsF
T
Off
1)
Power_on
3 Sec
Power_off
3 Sec
Min
100ms
 Min.
2Frame (Recommend: 2 sec)
msec
500
90
Falling Time of Vs (90% to 10%)
T
VsF
msec
2000
600
Time interval between 90% of  Vcc and 90% of Vs
when Power On
T
on
 +
T
VsR
msec
800
100
Rising Time of Vs (10% to 90%)
T
VsR
msec
300
50
Falling Time of Va (90% to 10%)
T
VaF
msec
300
10
Rising Time of Va (10% to 90%)
T
VaR
msec
-
20
Time interval between 10% of Vs and 90% of Vcc
 when Power Off
T
Off
msec
-
500
Time interval between 90% of Vcc and 10% of Vs
when Power On
T
On
unit
Max.
Min.
Description
Symbol
- 16 -
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
0
0
1
1
1
A7
W
Start
By
Master
 
Chip ID Address Byte
(0x1C)
ACK
By Slave
0
1
9
1
A6
A1
A0
Command Address
Addr=A[7:0]
0
Write
only
Master : Image Board
Slave : PDP Module
- 17 -
TROUBLE SHOOTING GUIDE
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