LG 50PT85 User manual

PLASMA TV
SERVICE MANUAL
CAUTION
BEFORE SERVICING THE CHASSIS,
READ THE SAFETY PRECAUTIONS IN THIS MANUAL.
CHASSIS : PD74A
MODEL : 50PT85 50PT85-ZB
website:htt ://biz.LGservice.com
Internal Use Only

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CONTENTS
SAFETY PRECAUTIONS ....................................................................................3
SPECIFICATIONS ................................................................................................4
ADJUSTMENT INSTRUCTIONS .........................................................................6
TROUBLE SHOOTING GUIDE..........................................................................13
BLOCK DIAGRAM.............................................................................................25
EXPLODED VIE ..............................................................................................26
EXPLODED VIE PARTS LIST ........................................................................27
REPLACEMENT PARTS LIST...........................................................................28
SCHEMATIC DIAGRAM.........................................................................................
PRINTED CIRCUIT DIAGRAM ..............................................................................

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SAFETY PRECAUTIONS
Many electrical and mechanical parts in this chassis have special sa ety-related characteristics. These parts are identi ied by in the
Schematic Diagram and Replacement Parts List.
It is essential that these special sa ety parts should be replaced with the same components as recommended in this manual to prevent
X-RADIATION, Shock, Fire, or other Hazards.
Do not modi y the original design without permission o manu acturer.
General Guidance
An isolation Transformer should always be used during the
servicing o a receiver whose chassis is not isolated rom the AC
power line. Use a trans ormer o adequate power rating as this
protects the technician rom accidents resulting in personal injury
rom electrical shocks.
It will also protect the receiver and it's components rom being
damaged by accidental shorts o the circuitry that may be
inadvertently introduced during the service operation.
I any use (or Fusible Resistor) in this monitor is blown, replace it
with the speci ied.
When replacing a high wattage resistor (Oxide Metal Film Resistor,
over 1W), keep the resistor 10mm away rom PCB.
Keep wires away rom high voltage or high temperature parts.
Due to high vacuum and large sur ace area o picture tube,
extreme care should be used in handling the Picture Tube.
Do not li t the Picture tube by it's Neck.
Leakage Current Cold Check(Antenna Cold Check)
With the instrument AC plug removed rom AC source, connect an
electrical jumper across the two AC plug prongs. Place the AC
switch in the on position, connect one lead o ohm-meter to the AC
plug prongs tied together and touch other ohm-meter lead in turn to
each exposed metallic parts such as antenna terminals, phone
jacks, etc.
I the exposed metallic part has a return path to the chassis, the
measured resistance should be between 1MΩ and 5.2MΩ.
When the exposed metal has no return path to the chassis the
reading must be in inite.
An other abnormality exists that must be corrected be ore the
receiver is returned to the customer.
Leakage Current Hot Check (See below Figure)
Plug the AC cord directly into the AC outlet.
Do not use a line Isolation Transformer during this check.
Connect 1.5K/10watt resistor in parallel with a 0.15uF capacitor
between a known good earth ground (Water Pipe, Conduit, etc.)
and the exposed metallic parts.
Measure the AC voltage across the resistor using AC voltmeter
with 1000 ohms/volt or more sensitivity.
Reverse plug the AC cord into the AC outlet and repeat AC voltage
measurements or each exposed metallic part. Any voltage
measured must not exceed 0.75 volt RMS which is corresponds to
0.5mA.
In case any measurement is out o the limits speci ied, there is
possibility o shock hazard and the set must be checked and
repaired be ore it is returned to the customer.
Leakage Current Hot Check circuit
1.5 Kohm/10W
To Instrument's
exposed
METALLIC PARTS
Good Earth Ground
such as WATER PIPE,
CONDUIT etc.
AC Volt-meter
IMPORTANT SAFETY NOTICE
0.15uF

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SPECIFICATIONS
NOTE : Speci ications and others are subject to change without notice or improvement .
VApplication Range
This spec is applied to the 50” PLASMA TV used PD74A Chassis.
V Specification
Each part is tested as below without special appointment.
1) Temperature : 25±5°C (77±9°F), CST : 40±5
2) Relative Humidity: 65±10%
3) Power Voltage: Standard Input voltage (100-240V~, 50/60Hz)
* Standard Voltage o each product is marked by models.
4) Speci ication and per ormance o each parts are ollowed each drawing and speci ication by part number in accordance with SBOM.
5) The receiver must be operated or about 20 minutes prior to the adjustment.
VTest Method
1) Per ormance : LGE TV test method ollowed.
2) Demanded other speci ication
Sa ety : CE, IEC speci ication
EMC : CE, IEC
VGeneral Specification ( 50” XGA Module)
Chassis
PD74A 50PT85 UK,France, Germany, Spain,
Sweden, Finland, Italy
LG
Model Name Market Brand Remark
50PT85 Sa ety : IEC/EN60065
EMI : EN55013, EMS : EN55020
UK,France, Germany, Spain,
Sweden, Finland, Italy
Model ApplianceMarket
Not yet TEST
Remark
Display Screen Device
Aspect Ratio
PDP Module
Operating Environment
Storage Environment
Input Voltage
1
2
3
4
5
6
No Item Speci ication Remark
50” Wide Color Display Module
16:9
PDP50X4A,
RGB Closed Type
1)Temp. : 0~40deg
2)Humidity : 0~85%
3)Temp. : -20~60deg
4)Humidity : 0~85%
100-240V~, 50/60Hz
Plasma Display Panel
Glass Filter
LGE SPEC.
Maker : LG

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VModule Specification
Market
Broadcasting system
Receiving system
SCART Jack(2EA)
Video Input (2EA)
S-Video Input (1EA)
Component Input (1EA)
RGB Input
HDMI Input(2EA)
Audio Input(4EA)
1
2
3
4
5
6
7
8
9
10
No Item Speci ication Remark
UK,France, Germany, Spain,
Sweden, Finland, Italy
1) PAL-BG
2) PAL - DK
3) PAL - I, I’
4) DVB - T(ID TV)
Analog : Upper Heterodyne
Digital : COFDM
PAL, SECAM
PAL, SECAM, NTSC
PAL, SECAM, NTSC
Y/Cb/Cr, Y/Pb/Pr
RGB-PC
RGB-DTV
HDMI-PC
HDMI-DTV & SOUND
PC Audio, Component, AV(2EA)
UK,France, Germany, Spain,
Sweden, Finland, Italy
Scart 1 Jack is Full scart and support RF-OUT
(analog)
Scart 2 Jack is Hal scart and support MNT-OUT
4 System : PAL, SECAM, NTSC, PAL60
4 System : PAL, SECAM, NTSC, PAL60
L/R Input

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ADJUSTMENT INSTRUCTIONS
1. Application Object
These instructions are applied to all o the 42” PLASMA TV,
PD74A Chassis.
2. Note
(1) Because this is not a hot chassis, it is not necessary to use
an isolation trans ormer. However, the use o isolation
trans ormer will help protect test instrument.
(2) Adjustment must be done in the correct order.
(3) The adjustment must be per ormed in the circumstance o
25±5°C o temperature and 65±10% o relative humidity i
there is no speci ic designation.
(4) The input voltage o the receiver must keep 100-240V~,
50/60Hz.
(5) Be ore adjustment, execute Heat-Run or 30 minutes at RF
no signal.
3. Channel memory Setting Method
: You can set channel memory by R/C or adjustment.
1)
Press ADJ key o Adjust Remote Controller.(P/N:105-210M)
2) Select ‘Channel Recover’ by using D/E(CH +/-) key, and
press ‘VOL +’.
3) The set is turned o automatically.
4) Press ‘power’ key o Adjust Remote Controller.
4. PCMCIA CARD Checking Method
: You must adjust DTV ##(Scrambled) Channel and insert
PCMCIA CARD to socket.
1) I PCMCIA CARD works normally, normal signals display
on screen.
But it works abnormally, “No CA module” words display on
screen.
5. PO ER PCB Assy Voltage
Adjustments (Va, Vs Voltage adjustments)
5-1. Test Equipment : D.M.M. 1EA
5-2.Connection Diagram for Measuring
: re er to Fig.1
5-3. Adjustment Method
(1) Va Adjustment
1) A ter receiving 100% Full White Pattern, HEAT RUN.
2) Connect + terminal o D.M.M to Va pin o P805, connect
- terminal to GND pin o P805.
3) A ter turning VR901, voltage o D.M.M adjustment as
same as Va voltage which on label o panel right/top.
(Deviation; ±0.5V)
(2) Vs Adjustment
1) Connect + terminal o D.M.M to Vs pin o P805, connect
– terminal to GND pin o P805.
2) A ter turning VR951, voltage o D.M.M adjustment as
same as Va voltage which on label o panel right/top.
(Deviation; ±0.5V)
Each PCB assembly must be checked by check JIG set.
(Because power PCB Assembly damages to PDP Module,
especially be care ul)
(Fig.1) Connection diagram o power adjustment or measuring
<42” EAY3292701>

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6. EDID (The Extended Display
Identification Data)/ DDC (Display
Data Channel) download
* Caution
(1) Use the proper signal cable or EDID Download.
- Analog EDID : Pin3 exists.
- Digital EDID : Pin3 exists.
(2) Never connect HDMI & DVI-D & DVI-A Cable at the same
time.
(3) Use the proper cables below or EDID Writing.
6-1. EDID Date
6-2. Setting of device
6-3. Preparation for Adjustment
1) As above Fig. 2, Connect the Set, EDID Download Jig, PC
& Cable.
2) Turn on the PC & EDID Download Jig. And Execute the
S/W : EDID TESTER Ver,2.5.
3) Set up S/W option.
Repeat Number : 5
Device Address : A0
PageByte : 8
4) Power on the Set.
6-4. Sequence of Adjustment
- EDID Download
1) Init the data.
2) Load the EDID data.(Open File).
[Analog ile] ( or RGB)
[Digital ile] ( or HDMI)
3) Set the S/W as below.
4) Push the “Write Data & Veri y”button. And con irm “Yes”.
5) I the writing is inished, you will see the “OK” message.
6) I TV has two HDMI, you must download two times or
each HDMI.
(Fig. 2) Connection Diagram o DDC download
Open FileOpen File
Item
Manu acturer ID
Version
Revision
Condition
GSM
Digital : 1
Digital : 3
Hex Data
1E6D
01
03
For RGB EDID
D-sub to D-sub
For HDMI EDID
DVI-D to HDMI or HDMI to HDMI

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- EDID DATA
1) Analog RGB(128Byte).
2) HDMI1 RGB(256Byte).
=> Detail EDID Options are below( ,,,,-1, -2, -1, -2)
3) HDMI1 RGB(256Byte).
=> Detail EDID Options are below( ,,,,-1, -2, -1, -2)
1. -> Product ID
2.
-> Serial No : Controlled on production line
3.
-> Month, Year : Controlled on production line
ex) Week : '03' => '03'
Year : '2006' => '10'
4.
-> Model Name(Hex):
5.
-1, -2, -1, -2 -> Checksum : Changeable by total
EDID data
7. ADC Calibration
Model Name
42PT85-ZB
50PT85-ZB
-1
89
8A
-2
C2
C3
-1
CC
CC
-2
F2
BC
Model
Name
42PT85
50PT85
Product ID
Product ID EDID table
B69C
B69C
Dec Hex
9CB6
9CB6
Model Name
42PT85-ZB
50PT85-ZB
Hex Data
000000FC003432505438350A202020202020
000000FC003530505438350A202020202020
- System control RS-232 Host should be “PC“ or adjustment.
- Be ore AV ADC Calibration, execute the “Panel size selection“
ADC RF/AV/S-VIDEO Component RGB-PC
MSPG925FS PAL Model:215 (720P) Model: 60
INPUT SELECT AV3 Pattern:65 (1024*768 60Hz)
Model: 202 (PAL-BGDHI) 720P/50Hz Pattern: 65
Pattern: 65 7 Color Bar
PAL 7 Color Bar

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8. Auto RF/AV/S-VIDEO Color Balance
8-1. Requirement
VThis AV color balance adjustment should be per ormed
be ore white Balance Adjustment.
8-2. Required Equipment
1) Remote controller or adjustment.
2) MSPG-925FS Pattern Generator (Which has Video Signal:
7 Color Bar Pattern shown in Fig.3).
(1) Model: 202 / Pattern: 65 - Models use PAL-BGDHI.
(composite signal)
8-3. Method of Auto RF/AV/S-VIDEO Color
Balance(PAL_BGDHI)
1) Input the PAL Video signal 7 color Bar (MSPG-925FS
Model : 202, pattern : 65) signal into AV3.
2) Set the PSM to Dynamic mode in the Picture menu.
3) Press INSTART key on R/C or adjustment.
4) Press the G(Vol. +) key operate to set, then it becomes
automatically.
5) Auto-RGB OK means completed adjustment.
9. Adjustment of Component
9-1. Requirement
VThis AV color balance adjustment should be per ormed
be ore white Balance Adjustment.
9-2. Required Equipment
1) Remote controller or adjustment.
2) MSPG-925FS Pattern Generator (Which has Video Signal:
7 Color Bar Pattern shown in Fig.5).
(1) Model: 215 / Pattern: 65 - Models use component.
9-3. Method of Auto Component Color Balance
1) Input the Component 720p/50Hz 7 Color Bar (MSPG-
925FS Model : 215, pattern : 65) signal into Component.
2) Set the PSM to Dynamic mode in the Picture menu.
3) Press IN-START key on R/C or adjustment.
4) Press the G(Vol. +) key to operate the set, then it becomes
automatically.
5) Auto-RGB OK means the adjustment is completed.
10. Adjustment of RGB
10-1. Requirement
VThis AV color balance adjustment should be per ormed
be ore white Balance Adjustment.
10-2. Required Equipment
1) Remote controller or adjustment.
2) MSPG-925FS Pattern Generator (Which has Video Signal:
7 Color Bar Pattern shown in Fig.7).
(1) Model: 3 / Pattern: 65 - Models use RGB
10-3. Method of Auto RGB Color Balance
1) Input the PC 1024x768 @ 60Hz 7 color bar (MSPG-925FS,
Model : 3, Pattern : 65) signal into RGB.(using D-sub to D-
sub cable)
2) Set the PSM to Dynamic mode in Picture menu.
3) Press the IN-START key on R/C or adjustment.
4) Press the G(Vol. +) key operate to set , then it becomes
automatically.
5) Auto-RGB OK means adjustment is completed.
(Fig.3) Color Bar signal
(Fig.4) Color Bar signal
(Fig.5) Color Bar signal
(Fig.6) Color Bar signal
(Fig.7) Color Bar signal
(Fig.8) Color Bar signal

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11. Scart RGB(DVR) Adjustment Mode
11-1. Required Equipment
1) Remote controller or adjustment
2) MSPG-925FS Pattern Generator (Which has Video Signal:
7 Color Bar Pattern shown in Fig.9)
(1) Model: 232 / Pattern: 08
11-2. Method of Auto Scart RGB(DVB) Balance
1) Input the Video Signal : Color Bar signal into AV1(using Full
Scart Cable).
2) Set the PSM to Dynamic mode in Picture menu.
3) Press the IN-START key on R/C or adjustment.
4) Press the TURBO-PICTURE Key on R/C or adjustment.
5) Press the G(Vol. +) key operate To set , then it becomes
automatically.(Fig.7)
6) Scart RGB(DVR) OK means Scart RGB adjustment is
completed.
12. Adjustment of hite Balance
12-1. Required Equipment
(1) Color Analyzer(CA-100+/CH.10)
1) Remote controller o adjustment -> Color Analyzer(CA-
100+ o same product) : CH 10
2) Auto W/B adjustment instrument.(only or Auto
Adjustment) -> AV Pattern Generator.
W Color temperature standards according to CSM and Module.
W White balance adjustment coordinate and color temperature.
* PC( or communication through RS-232C)
-> UART Baud rate : 115200 bps
* Luminance Y AV : upper 150cd/m2 (Typ : 350cd/m2)
-> Applying to Cool, Medium, Warm mode.
12-2. Connection Picture of the Measuring
Instrument(On Automatic control)
(1) Inside PATTERN is used when W/B is controlled. Connect
to auto controller or push control R/C IN-START -> Enter
the mode o White-Balance, the pattern will come out.
power supply) and heat-run over 15 minutes.
(Fig.10) Color bar Signal
(Fig.11) Auto AV(CVBS) Color Balance Test Pattern
Full White Pattern
RS-232C Communication
CA-210
Color
ANALYZER
TYPE : CA-210
(Fig.9) Color Bar signal
PLASMA Remark
11000K
9300K
6500K
Cool
Normal
Warm
CSM
Cool CS-100 CA-210(CH 10)
x 0.276 0.276±0.002
y 0.283 0.283±0.002
∆uv 0.000 0.000
Medium CS-100 CA-210(CH 10)
x 0.285 0.285±0.002
y 0.293 0.293±0.002
∆uv 0.000 0.000
arm CS-100 CA-210(CH 10)
x 0.313 0.313±0.002
y 0.329 0.329±0.002
∆uv 0.004 0.004

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V Auto adjustment Map(RS-232C)
12-3. Auto-control interface and directions
(1) Adjust in the place where the in lux o light like loodlight
around is blocked.(illumination is less than 10ux)
(2) Measure and adjust a ter sticking the Color Analyzer(CA-
100+, CA-210) to the side o the module.
(3) Aging time
- A ter aging start, keep the power on(no suspension o
power supply) and heat-run over 15minutes.
- Keep white pattern using inside pattern.
13. Adjustment of hite Balance
(Manual white Balance)
V One o R Gain/ G Gain/ B Gain should be kept on 80, and
others are controlled lowering rom 80
(1) press “power on” o the control R/C, set heat run to white
by pressing Gand heat run over 15 minutes.
(Set: RS-232 Host: PC, Baud Rate: 115200bps,
Download: Cortez)
2) Zero Calibrate CA-100+, and when controlling, stick the
sensor to the center o PDP module sur ace.
3) Double click In-start key on Controlling R/C and get in
‘white balance’.
4) Set test-pattern on and display inside pattern. Control is
carried out on three color temperature, COOL, MEDIUM,
WARM. (Control is carried out three times,)
5) When the R/G/B GAIN is 80 on OSD, it is the FULL
DYNAMIC Range o the Module. In order to control white
balance without the saturation o FULL DYNAMIC Range
and DATA, one o R Gain / G Gain / B Gain should be kept
on 80, and other two is controlled lowering rom 80.
* Color Temperature: Cool, Medium, Warm
(1) When R GAIN is set to 80
- Control G GAIN and B GAIN by lowering rom 80.
(2) When B GAIN is set to 80
- Control R GAIN and G GAIN by lowering rom 80.
(3) When G GAIN is set to 80
- Control R GAIN and B GAIN by lowering rom 80.
One o R Gain / G Gain / B Gain should be kept on 80, and
adjust other two lower than 80.
(When R/G/B GAIN are all 80, it is the FULL DYNAMIC
Range o Module).
14. Default Value in Adjustment mode
14-1. Auto Color Balance
14-2. rite Balance
(Fig.12) De ault Value on OSD
<Component> <RGB>
(Fig.13) De ault Value on OSD
Type PD74A
Baud Rate Data bit Stop bit Parity
115200 8 1 None
Protocol Index Cmd 1 Cmd 2 Data Min Value Max Value
Setting R-Gain_Normal j a 00(00) 128(80)
G-Gain_Normal j b 00(00) 128(80)
B-Gain_Normal j c 00(00) 128(80)
R-Gain_Warm j d 00(00) 128(80)
G-Gain_Warm j e 00(00) 128(80)
B-Gain_Warm j 00(00) 128(80)
R-Gain_Cool j g 00(00) 128(80)
G-Gain_Cool j h 00(00) 128(80)
B-Gain_Cool j i 00(00) 128(80)
R-O set_Normal l j 00(00) 128(80)
G-O set_Normal l k 00(00) 128(80)
B-O set_Normal l l 00(00) 128(80)
R-O set_Warm l m 00(00) 128(80)
G-O set_Warm l n 00(00) 128(80)
B-O set_Warm l o 00(00) 128(80)
R-O set_Cool l p 00(00) 128(80)
G-O set_Cool l q 00(00) 128(80)
B-O set_Cool l r 00(00) 128(80)
Internal Pattern Signal w b 00 W/B adjustment Start
Internal Pattern Signal w b 10 Internal Pattern use
Internal Pattern Signal w b W/B adjustment end

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15. Set information(Serial No & Model name)
(1) Setting up like bottom igure (A ter setting white balance,
this is set)
1) Press ADJ Key in the Adjust remocon.
2) Select “System Control 2” by using D/E(CH+/-) key,
and press A(ENTER).
3) Using Adjust remocon, RS-232 Host & Baud Rate &
Download value change (RS-232 Host:Gprobe, Baud
Rate:115200bps, Download:Cortez)
(2) Bar-code scanning
1) Push the menu button in DTV mode.
Select the STATION -> Diagnostics -> To set
2) Check the Serial Number.
16. Select method of Tool option
(1) Press ADJ Key in the Adjust remote control.
(2) Select “Tool option 1” and “Tool option2” by using D/E
(CH+/-) key, and press A(ENTER).
(3) TOOL OPTION1
1) Select “Maker” by using D/E(CH+/-) key, and change
the module maker and. applied module classi ication by
using F/G(VOL+/-).
2) Select “Inch” by using D/E(CH+/-) key, and change the
module according to the inch o model.
(4) TOOL OPTION2
1) Select “TOOL NUM” by using D/E(CH+/-) key, and
change the module maker and. applied module
classi ication by using F/G(VOL+/-).
2) Select “FAN” by using D/E(CH+/-) key, change the
module according to the inch o model.
3) Select “DIGITAL” by using D/E(CH+/-) key, and change
the tool name according to the model.
( Inch o model : “42,50” Applied module under the calassi icatoin : )
6) A ter changing the Tool option1,2, push the EXIT Key.
Tool option1 Maker Inch Tool
2048 LGX4 42 PT85
2052 LGX4 50 PT85
Tool option2 Su ix FAN DIGITAL AMP
1665 KE*L(Y)LMP 0 1
1921 KE*L(Y)LMP 1 1
1665 KE*FLMP 0 1

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TROUBLE SHOOTING GUIDE
1. Power Board
1-1. The full flowchart for the voltage output
Start check
Manu acture’s model
passage
1. Check the Power O
status.
Does the whole
screen appear?
Is it
identical to when the
power is o ?
No
Yes
No
Yes
Yes
Yes
Yes
2. Check the Inter ace
signal status.
Is the Inter ace
signal operating?
Yes
3. Check the St-by 5V
signal circuit.
Does the
low pressure output
appear?
Does the
St-by 5V signal
appear?
No
No
Yes
4. Check the 5V Monitor
signal circuit.
Does the
5V Monitor signal
appear?
No
7. Check the VSC Vs-ON
signal
Does the
high tension output
appear?
Does the
VSC signal Vs-ON
appear?
No
No
Does the
high tension
output voltage
occur?
When
removing the Y B/D
Module input connector,
does output voltage
drop?
When the
Y, Z B/D Module
input connector, does Power
Board high tension
output voltage drop?
No No No
9. Check the Power
Board Output high
tension circuit
Yes
10. Check the Z B/D
Module output circuit
Yes
When
removing the Z B/D
Module input connector,
does output voltage
drop?
11. Check the Y B/D
Module output circuit
Yes
Yes
8. Check the Vs, Va
voltage output circuit.
Does the
Vs, Va voltage output
appear?
No
Yes
Yes
5. Check the VSC RL-ON
signal.
Does the
VSC signal RL-ON
appear?
No
6. Check the VSC low
pressure output
Does the
VSC low pressure
output appear?
No

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1-2. 50” Power Board Structure(EAY32927901)
(1) Pin Layout
(2) Pin Spec
SC101 P800 P802 P803 P811 P812
AC INLET ANALOG & DIGITAL BOARD PDP MODULE
AC
NC
AC
YH396-03V
AC Det
RL-ON
STBY 5V
GND
Vs-ON
5V Det
M5V-ON
STBY 5V
GND
NC
6V
GND
3.4V-ON
SMW250-13P
19V
19V
GND
GND
6V
GND
3.4V
GND
12V
GND
SMW250-10P
3.4V
3.4V
GND
GND
6V
6V
GND
GND
12V
12V
GND
GND
SMW250-12P
5V
5V
GND
GND
YH396-04V
Va
Va
GND
GND
GND
GND
NC
Vs
Vs
Vs
YH396-10V
1
2
3
4
5
6
7
8
9
10
11
12
13
Description
NO

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2. No Power
(1) Symptom
1) Does not minute discharge at module.
2) Non does not come into the ront LED.
(2) Procedure check
Is the power cord plugged in? Plug in the power cord.
Yes
No
Is the Line Filter and Power
Board Cable connected? Connect the Cable.
Yes
No
Is the appropriate Fuse(F101) on
the Power Board? Replace the Fuse.
Yes
No
Is the Power Board and 13P o
VSC Board Cable connected? Connect the Cable.
Yes
No
A ter removing the cables, connect them to the Power Board(except the
SC101 connection cable), and change the AC voltage marking to manual.
When ST-BY 5V does not operate, replace the Power Board.

- 16 - LGE Internal Use OnlyCopyright © 2007 LG Electronics. Inc. All right reserved.
Only or training and service purposes
3. Protect Mode
(1) Symptom
1) A ter lighting up once, it does not discharge
minutely rom module.
2) The rely alls.(there is an audible “click”)
3) The color o the ront LED turns rom green to red.
(2) Procedure check
Is the Power Board
normal ? Replace the Power Board.
Is the output Low/High voltage normal
except or Stand-by 5V?
Yes
No No
Is the each connector
normal? Replace the connector.
Replace the
Y-Board.
A ter connecting each connector do
they operate normally?
Yes
No Yes
Is the Ctrl Board
normal?
Replace the
X-Board.
Is the output voltage normal a ter
removing P1, 2, 4, 9, 10 connectors o
the Ctrl-B/D?
Yes
No Yes
Is the Y-Board
normal?
Is the output voltage
normal a ter removing
P103 connector o
Y-B/D?
Is the appropriate Fuse(FS101,FS102)
on the Y-B/D normal?(Replace i open)
Yes
No Yes Yes
Replace the
Z-Board.
Is the Z-Board
normal?
Is the output voltage
normal a ter removing
P1 connector o
Z-B/D?
Is the appropriate Fuse (FS1, FS2) on
Z-B/D? (replace i open)
Yes
No Yes
Is the X- Board
normal?
Is the output voltage normal a ter
removing P1, 2, 3, 4, 5 connectors o
the X-B/D?
I the output voltage is normal a ter removing
the P1, P2, P3 : Replace the right X-B/D
I the output voltage is normal a ter removing
the P4, P5 : Replace the le t X-B/D
Yes
No Yes
Is the
VSC Board normal?
Is the output voltage normal a ter
removing P900, P901 o VSC Board?
A ter a COF crisis or each board, check the normal operation. For normal operation,
corresponding COF ailure means the module should be relaced.
I it operates normally a ter removing the
P900, P901 : Replace the VSC Board
Yes
No
Is the COF o X, Y, Z
normal ?
No
Yes
Yes

- 17 - LGE Internal Use OnlyCopyright © 2007 LG Electronics. Inc. All right reserved.
Only or training and service purposes
Does minute discharge
At Module?
Is the LVDC cable
normal?
Is the VAVS on?
Check the PDP Module
Yes
No
YES
Yes
Reconnect the LVDS
cable in P1901
No
Is the IC700(FLI8548)
Output normal? Replace the VSC.
No
NO Replace the Power
board
Is the Low/High output
voltage normal except or
stand-by 5V?
NO
4. No Raster
(1) Symptom
1) No OSD and image occur at screen.
2) It maintains the condition where the ront LED is green.
(2) Procedure check

- 18 - LGE Internal Use OnlyCopyright © 2007 LG Electronics. Inc. All right reserved.
Only or training and service purposes
5. In case of strange screen display in specific modes
5-1. In case of no OSD display
(1) Symptom
1) LED is green.
2) The minute discharge is continuously accomplished rom the module.
(2) Procedure check
Is the LVDS cable
normal ?
Is the VSC Board
normal?
Is the LVDS cable
connected?
Re-insert the Cable.
Yes
No
No
Yes
Does the FIL8548
IC(IC700) operate?
Replace the FIL8548
IC(IC700)
No
Is the Ctrl Board o
Module normal? Replace the Ctrl B/D.
No
No
Yes
Replace the VSC B/D
Replace the cable.
Yes

- 19 -
5-2. In case there is no display on the screen in specific modes
(1) Symptom
1) There is no screen display rom a speci ic input mode
(RF, AV, Component, RGB, DVI).
(2) Procedure check
1) Check the all input modes have normal display .
Is the Tuner normal?
Is the CXA2069Q normal?
Is the Tuner Cable connected?
Re-insert the cable
Yes
No
No
Yes
Is the FIL8548 normal?
Replace the Tuner.
No
Are the Input voltage, IIC Communication
and CVBS output normal?
Yes
Are the Input voltage, IIC
Communication and HV sync normal?
No Replace the IC.
No
Are the input voltage, IIC
Communication and HV sync normal?
No
Block A
Replace the IC.
No
Is the Video input o the AV
Jack(P1400) normal?
Yes
Is the CXA2069Q normal?
Check the input source
No
Are the Input voltage, IIC
Communication and HV sync normal?
No
Replace the IC.
No
Yes
Same as Block A
(3) In case of an unusual display in RF mode
(4) In case of an unusual display in side S-video/ AV mode

- 20 - LGE Internal Use OnlyCopyright © 2007 LG Electronics. Inc. All right reserved.
Only or training and service purposes
Are the R,G,B input and H,V
Sync o the P1100 normal? Check the input source
No
Is the HDMI002(IC1004)
normal?
Yes
Same as Block A
Are Input voltage, IIC Communication
and HV sync normal?
No
Is the Video input o the
A/V Jack(J1200) normal?
Yes
Same as Block A
Check the input source
No
Replace the IC.
No
Is the Video input o the
A/V Jack(J1201) normal?
Yes
Same as Block A
Check the input source
No
Yes
Same as Block A
(5) In case of an unusual display in Component, RGB mode
(6) In case of an unusual display in HDMI mode
(7) In case of an unusual display in SCART1 mode
(8) In case of an unusual display in SCART2 mode