PDP One Point Repair GuidePDP One Point Repair Guide
1.1. GeneralGeneral2.2. 40 ~ 50 Inch Practice40 ~ 50 Inch Practice3.3. 60 Inch Practice60 Inch Practice
PCB Pattern Short
1. Check after X-Board change
2. Do shortage check neighboring pins of FPC* connector
3. Check soldering condition of defect pin
4. Scan the pattern connected to defect pin with Microscpoe
Change X board
Symptom Cause Countermeasure
CHECK PointCHECK Point
*FPC : Flat Pin Connector
Red Bar at left lower
(Bad X-Board PCB)
2/88 LG Electronics / DND / QA Gr.
Red & Green pin of left lower 4th FPCshort
Defect Point : Short on the PCB just above connector
PCB
1. Cause : Short by solder bridge - Can not observe with naked eye - When connector open, pattern is OK
G R
Change X-Board
1. Check the contact status with connector(foreign material, soldering condition)
2. Replace X Board and check again.(If OK, X-Board is defected)
3. By tracing defected line, check the contact condition of FPC and other connectors, IC output stage and PCB pattern.
4. If no problem, check the connector lead board.
Symptom Cause Countermeasure
Check PointCheck Point
3/88 LG Electronics / DND / QA Gr.
Bottom Right 6th FPC R/B Short
Pattern Short by connector miss insert Re-insert the Connector
Symptom Cause Countermeasure
Check PointCheck Point
1. Check the contact status with connector(foreign material, soldering condition)
2. Replace X Board and check again.(If OK, X-Board is defected)
3. By tracing defected line, check the contact condition of FPC and other connectors, IC output stage and PCB pattern.
4. If no problem, check the connector lead board.
4/88 LG Electronics / DND / QA Gr.
SHORT
ADD Electrode short at R,G,B Rasteror White Screen(Different color display)
Foreign Material(Iron powder)in the Connector
Insulation tape
Gap
Apply silicon on the Connector lead ←Pay attention to a capillary symptom
↓
X-Board Tape Rework
1. Trace defected line
2. Check the condition of FPC and connector on the X-Board, IC Output stage and Electrode line.
Check PointCheck Point
Symptom Cause Countermeasure
5/88 LG Electronics / DND / QA Gr.
OPEN
1. Outbreak during heat run2. ADD Electrode open at one color Raster or White screen(No discharge)
Interfere with mechanicalstructure when Moduleassembling
Keep horizontal, orcan be defected
Cold soldering atConnector
Use Connector fixing iron plate ⇒ Keep the contact point horizontal when interfere with mechanical parts
1. Trace defected line and check the condition of FPC and connector on X-Board, IC Output stage and
Electrode line.
FPC connector Rework
Symptom Cause Countermeasure
Check PointCheck Point
6/88 LG Electronics / DND / QA Gr.
ADD Pattern
Connected minutely and open slowly as time passes
1. Replace X Board and check again(Still problem, change the Panel)2. Check the connection status of Panel side.3. Check the connection condition of connector of Panel side and the FPC at upper ACF. → If it is OK, check Panel pad
ADD open
Replace the Panel
Symptom Cause Countermeasure
Check PointCheck Point
7/88 LG Electronics / DND / QA Gr.
Panel Electrode
ACFFPC
Electrode
Open Electrode(16)
Resistance A
Resistance B
ADD Electrode openat Green Raster
~
~
1. ADD pattern of PAD siden open2. Width : 10 um
Resistance A Resistance B
16pin
1,3,15,17,19pin
1.2Ω 6.0Ω
1.0 ~1.2Ω 2.2~2.4Ω
1. Check the connection condition - Press the connector and reconnect2. Check the soldering condition of Connector lead3. Replace X Board and check again; Panel connector side or Circuit connector side → Board defect, in case of one line, check the output stage of Drive IC(Cold soldering/Pattern) If problems in input stage, several lines display
Replace the Panel
* The difference of ADD open and Short ? ADD open : Black vertical bar at Raster ADD short : Different color vertical bar at Raster
CountermeasureSymptom & Cause
Check PointCheck Point
8/88 LG Electronics / DND / QA Gr.
< Raster > < White >
ADD short at raster screen and ADD open atwhite screen appear at some area after 20minute HeatRun.
Con 1 Con 2
Control board
X-board
Solder bridge
1. Check the 5V(Logic voltage) input to DC-DC → If it is lower than 5V, it makes similar problem2. Check X Board(Open or Short circuit)3. Check the connection condition(conncetion status, foreign material at connector, etc)4. Check the drive IC at X Board(If defected, change the Board)5. Confirm the connection of the connector
Change Control Board
Symptom Cause Countermeasure
Check PointCheck Point
9/88 LG Electronics / DND / QA Gr.
Driver clock line at X Driver Board is designed to operate in A and B group
Short circuit at clock line of Drive IC
If problem at input stage, several lines are defected at one point
Replace the X Board of defected point
PCB pattern shortShort
CLK LE
X-DRV IC
SN74ACT541
U1
R264R258
Change X-BOARD
Check PointCheck Point
Symptom Cause Countermeasure
10/88 LG Electronics / DND / QA Gr.
<X-board>
1. Check the connection condition of the Connector.
2. Check the cold soldering.
X driverchip
(SN755851PJ)
1
64
Module
ChipResistors
4X16 = 64 data
16 clock
line1line2
line3line4
connector
Check PointCheck Point
Symptom Cause Countermeasure
ChangeX Board
ElectrodePattern
PCB pattern is connected minutely → Foreign material when photo resisting
11/88 LG Electronics / DND / QA Gr.
Vertical bar in every 20mm
Resistance between 186 pin of U3 and 7 pin of U300 is 62 Ω Normal condition : 2Ω
Because of foreign material in Via hole at U300 side
U3ALTERA Chip
U300DRAM
Via hole
186pin PIN 7pin PIN
Control board
1. Measure the resistance of Via holes between U3 and U300 at Control Board and compare with that of normal.(Normal : 2~3 Ω)2. Resistance increases as temperature rises.
Change Control Board
Check PointCheck Point
Symptom Cause Countermeasure
12/88 LG Electronics / DND / QA Gr.
- Open circuit between pin 7 of U200 and pin 7 of U7- Resistance between two pins varies from 19 ohm ~ 45Kohm
1. Observe the symptom during Heat-Run at 45 degree.
2. Check the resistance of VIA holes of suspect ICs
Replace Control Board
Check PointCheck Point
Symptom Cause Countermeasure
13/88 LG Electronics / DND / QA Gr.
D1 D3 D4 PROM(U40)
FPGA
D1 D3 D4 PROM(U40)
FPGA
CONTROL BOARD
* For normal operation, PROM program should be downloaded to FPGA, and each PROM has corr- espondent FPGA. See left picture.
1. Because Control data on PROM(U40) doesn’t download to FPGA, it can’t generate control signal to X,Y and Z Board.2. Defected ALTERA.
1. Check D1, D3 & D4 on Control Board - D1 : ON with 5V - D3 : ON when PROM finishes program download from ALTERA chip - D4 : ON when signal is applied
•Replace Control Board•Replace PROM
- When Power On, Fan operates but No OSD displays- LED(D3) of Control Board doesn’t operate
Check PointCheck Point
Symptom Cause Countermeasure
14/88 LG Electronics / DND / QA Gr.
Touch point(Marked)
No signal or at PC mode, dark red raster displays.This is darker than normal Red signal.
- TV VSC board - Board connector(50 pin) contact point - Control board of Module
Neighboring Pins of U1(FPGA) touch
Control Board
Replace Controller board
Check PointCheck Point
Symptom Cause Countermeasure
15/88 LG Electronics / DND / QA Gr.
1. No Raster(ST-BY LED On)2. Spark noise(Tik-Tik)3. No Vs, Vsetup & Vsc
1. CN1 on Vs Board cold soldering2. Spark marks between CN1 and Vs Board -> It makes them open
Solder land
Soldering Direction
Solder
Soldering Direction
Soldering point
Vs board
CN1
1. Check Vs, Va with multimeter(No Vs output)
2. Separate SMPS Board and VSC Board and check all voltage output stage
3. Check FET, TR, Diode and Resistor(especially Cement Resistor)
4. Observe PCB Pattern and soldering condition with naked eyes
Replace DC-DC 2 board
Check PointCheck Point
Symptoms Cause Countermeasure
16/88 LG Electronics / DND / QA Gr.
17/88
P6
P4
Rework should be done
Y-Driver Board
Y-Board
42” PDP Flicker and 42” PDP Flicker and No Raster TroubleshootingNo Raster Troubleshooting Guide Guide
cause : bad connection between Y-Board # 1, 2 drive board Connector pin
42 Inch40 ~ 42 Inch
LG Electronics / DND / QA Gr.
18/88
amplified amplified
① : outside Leg : inside Leg②
•P 6, P 4 both are the first pin, when wiring, it should be done as picture shown. (bend the wire to Y-Driver B/D not to Y-B/D . If not there can be noise)
•Don’t be confused with Pin number
•Improved since Dec,2001.
P 4 ①
②
②
①
①
②①
②
①②
②①
P 6
LG Electronics / DND / QA Gr.
19/88
②
①②
②①
①
②
①
Be sure not to misconnect the line.See the picture precisely and then connect jump wire at the exact point
LG Electronics / DND / QA Gr.
20/88
X CANVAS X CANVAS
Intermittent no-image/image error while watching
The screen is intermittently disappeared . LED is green screen is distorted weiderly (happened 2 a day)
normal
cause : bad connection between Y-Board and #1, 2 pin of Y-Drive Board Connector
troubleshooting : connect bad linking between Y-Board & Y-Drive with jump wire (all 4 parts)
see working instruction(revised since Dec,2001. 1)
CANVASX
LG Electronics / DND / QA Gr.
21/88
X CANVAS
normal
CANVASX
No Power ( in ST-BY mode, but no LED)
Check the power supply & main power S/W on
Check EMI board fuse (check the rated capacity )
No Power
Fuse 15 A
Be sure to use rated fuse.
LG Electronics / DND / QA Gr.
22/88
X CANVAS
normal
CANVASX
when Power’s on, after 2 ~ 3 sec, it’s off ( LED changing green into red )
CHECK : remove STB and operate monitor individually. (check STB defect or Monitor defect )
When using ANALOG STB, check STB only MN-42PZ10 only STB : RN-BA11
Remove each Board’s power supply connector and check the power is off.When the power is not off,replace the related board.
No Raster
LG Electronics / DND / QA Gr.
23/88
X CANVAS
normal
CANVASX
no picture (LED’s green)
Core checkpoint : remove STB and operate monitor individually. (check whether STB’s a defect or monitor’s one)
No Picture
With monitor defect, check VSC and then Controller Board.
Troubleshooting : replace VSC Board
LG Electronics / DND / QA Gr.
24/88
X CANVAS
normal
CANVASX
no image (LED’s green)
Cause : Y-Drive ( Bottom ) defect
Troubleshooting : Y-Drive (lower part) replacement
Address Bar ( Horizontal Bar )
Y-Drive Board ( Bottom )
This problem is shown in the bottom of screen,So it is caused by Y-Drive
LG Electronics / DND / QA Gr.
25/88
X CANVAS
normal
CANVASX
no image (LED’s green)
Address Bar ( Horizontal Bar )
Y-Drive Board ( Top )
Cause : Y-Drive Board (upper part) defect
Troubleshooting : Y-Drive Board replacement
LG Electronics / DND / QA Gr.
26/88
X CANVAS
normal
CANVASX
no image (LED’s green)
PD501 Connector
No Picture
cause : PD-501 Connector contact point defect
troubleshooting : PD-501 Connector replacement
(with PD-501 Connector contact point defect,Various defect symptoms can be seen)
LG Electronics / DND / QA Gr.
27/88
X CANVAS
normal
CANVASX
normal picture with high frequency noise (“bee”)
High frequency noise (“Bee” sound)
C8178 0.22uF electrolytic capacitor insertion
Open C8139 right lead and then wire R8164 right lead
Power (SMPS) Board
1. C8178 0.22 /50V add2. Open C8139 right lead, and then connect it to R8164 right lead.
Improved since Nov,2001
SMPS is supposed to operatewith high frequency sosmall noise is not considered as a defect.
#. Slight noise is not a defect and write down explanation
LG Electronics / DND / QA Gr.
28/88
X CANVAS
normal
CANVASX
No picture in right- 2/5 area
No picture in the right- 2/5 area
X-Board ( Left ) power supply check
X-Board ( Left )Connector check
X-Board ( Left ) replacement
LG Electronics / DND / QA Gr.
29/88
X CANVAS
normal
CANVASX
Address Bar (Vertical )
stripe in right-2/5 area
X-Board ( Left ) power supply check
X-Board ( Left ) Connector check
X-Board ( Left ) replacement
LG Electronics / DND / QA Gr.
30/88
X CANVAS
normal
CANVASX
X-Board ( Right ) power supply check
X-Board ( Right )Connector check
X-Board ( Right ) replacement
left 3/5 of screen with vertical stripes
No picture in left 3/5 of the screen
LG Electronics / DND / QA Gr.
31/88
X CANVAS
normal
CANVASX
X-Board ( Right ) power supply check
X-Board ( Right )Connector check
X-Board ( Right ) replacement
Address Bar (Vertical )
left 3/5 of screen with vertical stripes.
LG Electronics / DND / QA Gr.
32/88
X CANVAS
normal
CANVASX
no Red ( B or G )
Be sure not to bend it by force or internal Insulated conductor can be down.
Test Monitor individually.If detect a problem with monitor, check VSC Board.
If it has a problem with STB connecting, focus on 25 Pin.
Be sure not to connect 5 Pin (AP-EA10) by force
25 Pin Cable P/No : GVZ AP-EA10
No Red
LG Electronics / DND / QA Gr.
33/88
Lift up the right and left of X-BOARD CONNECTOR. Lift up X-BOARD CONNECTOR and separate COP CONNECTOR by pulling up.
When you handle COF CONNECTOR, don’t pressure. First release LOCK and separate.If COF CONNECTOR is damaged, you should replace MODULE ASS’Y. So, be aware of this!!
1) X - Board COF Connector separation
When you exchange X-Board, first you should separate COF Connector. Be careful to handle it.COF Connector is attached to Module. When COF Connector is broken, Module ASS’Y must be replaced a new one.
When you exchange X-Board, first you should separate COF Connector. Be careful to handle it.COF Connector is attached to Module. When COF Connector is broken, Module ASS’Y must be replaced a new one.
WarningWarning
COF Connector
42 Inch
LG Electronics / DND / QA Gr.
34/88
Lift up each edge of left/right. Lifted condition
2) X - Board Connector separation
It’s easy to separate it by releasing Connector Lock .
Do not pressure or it can be hurt. When LOCK is hurt, replace a new X-BOARD
WarningWarning
Be careful to handle LOCK or it can be broken. When LOCK is broken, replace a new X-BOARD.
LG Electronics / DND / QA Gr.
35/88
Pull the white LOCK as shown in arrow
Pull the white LOCK as shown in arrow.
Separate COF CONNECTOR by pulling in the left.
3) Y - Board COF Connector separation
WarningWarning
Be careful to handle LOCK and COF Connector. When LOCK part is damaged, you should replacea new Y-Board. In case of COF Connector, Module Assembly.
LG Electronics / DND / QA Gr.
36/88
4) Z - Board COF Connector separation
Separate the fixed Screw of Z-Board.Pull out Lock as shown in arrow.
Condition in Lock part is pulled Pull COF Connector as shown in arrow.
It’s easy to separate COF on conditionthat Z-Board Screw is separated. In case Z-Board is assembled, it’s reallyhard to separate.
Be careful not to tear COF Connector.If COF Connector is torn, replace a new Module Assembly
WarningWarning COF Connector
LG Electronics / DND / QA Gr.
37/88
Push LOCK and pull out
PUSH PUSH PUSH
5) Connector separation Guide
PUSH PUSH PULL
LG Electronics / DND / QA Gr.
38/88
6) Control Board & VSC Board Connector
LG Electronics / DND / QA Gr.
39/88
Be sealed up after gas injection
Be careful to handle the sealed-up part after gas injection. If it is broken, the gas escapes. So, replace the Module.
7) Gas injection (Sealing up) condition
WarningWarning
Be sealed up after gas injection
LG Electronics / DND / QA Gr.
40/88
Power is On and off 2~3 minutes.(Protection)
Power is On and off 2~3 minutes.(Protection)
P301 Connector Open Check.P301 Connector Open Check. X - Board Top Right Change.X - Board Top Right Change.
P302 Connector Open CheckP302 Connector Open Check X - Board Top Left Change.X - Board Top Left Change.
P303 Connector Open CheckP303 Connector Open Check
P304 Connector Open CheckP304 Connector Open Check
P102 Connector Open CheckP102 Connector Open Check
X - Board Bottom Right Change.X - Board Bottom Right Change.
X - Board Bottom Left Change.X - Board Bottom Left Change.
Z - Board Change.Z - Board Change.
P3, P2 Connector Open CheckP3, P2 Connector Open Check Y - Board Change.Y - Board Change.
P005, P003 Connector Open CheckP005, P003 Connector Open Check
P006 Connector Open CheckP006 Connector Open Check
VSC- Board Change.VSC- Board Change.
VSC - Board Change.Sound Output IC Short Check
VSC - Board Change.Sound Output IC Short Check
Power Board ChangePower Board Change
OK
OK
OK
OK
OK
OK
OK
OKPROTECT operation;
When the load voltage is short.
When each voltage doesn’t work (in general)
PROTECT operation;
When the load voltage is short.
When each voltage doesn’t work (in general)
8) Power off in 2 ~ 3 minutes(Protection)
LG Electronics / DND / QA Gr.
41/88
L813 Cold Solder
Check Check
Open the Connector connecting to each Board to check the power is off.if each Board is same, check the Power Board and voltage.
Symptom : As soon as the power on, it’s off in 2 - 3minutes. (PROTECT operation)Cause : No VS voltage L813 Coil cold soldering.
9) Power off in 2 ~ 3 minutes(Protection)
LG Electronics / DND / QA Gr.
42/88
MP-40PA10 uses 4 board such as left,right, top and bottom.Divide the screen in 4 and once you see ADD BAR check COF CONNECTORbetween MODULE and X-BOARD.If there is no defect in COF CONNECTOR replace X-BOARD.But the problem still remains and check the connector between X-BOARD andCONTROL BOARD. And if you can’t find defect, check CONTROL.
HEATRUN : WHITE
Press the ADJ KEY and check the position of add bar by changing WHITE orRED or BLUE or GREEN
Top Right Top Left
Bottom Right Bottom Left
10) ADD BAR inspection and repair
LG Electronics / DND / QA Gr.
43/88
Symptom : B color 1 Address line OpenCause : Dented COF
COF is dented
11) One Point Service Guide
LG Electronics / DND / QA Gr.
44/88
Symptom : Inferior R Address color Cause : Inferior DATA output by cold soldering 16 pin of IC14 in X-L-TOP ( Normal waveform after tearing off IC Pin)Countermeasure : Replace X-L-TOP board.
IC14
Cold Soldering
Abnormal waveform by cold soldering
Normal waveform after tearing off IC pin
LG Electronics / DND / QA Gr.
45/88
CheckCheck
The blue spreads on the screen (Mis-discharge) and power off in 2 ~ 3 seconds.If you turn on again, it will be same problem.
Symptom Causes Countermeasure
If 15V line voltage reduces below 14V,Mis-discharge occurs and power off because of protection circuit.
Replace PSU(Power Supply Unit)and defective X-Board.
If when Power on, screen shows like above and turn off in 2 seconds, check if turning off or not by disconnectingall X & Y boards.
Defective X-Board
LG Electronics / DND / QA Gr.
46/88
Check Check
The top left part of screen is broken(Top Right X-BOARD)
Symptom Cause Countermeasure
No 5V supply to Top rightX-Board.
Connect 5V line
Check Top right X-BOARD 5V.(If 0V, it happens)
Check 5V line from SMPS to X-BOARD.
LG Electronics / DND / QA Gr.
47/88
CheckCheck
Pinkish screen in the top left.(Top right X-BOARD)
Symptom Cause Countermeasure
No Va(70V) supply to Top right X-Board.
Connect 70V line
Check Top right X-BOARD Va(70V).(If 0V, it happens)
Check 70V(Va) line from SMPS to X-BOARD.
LG Electronics / DND / QA Gr.
48/88
CheckCheck
The 3/5 top left in the screen is blank(Top Right X-BOARD)
Symptom Cause Countermeasure
Check Top right X-BOARD 12V.( If 0V, it happens )
Check Top right X-BOARD Va(70V).(If 0V, it happens)
Check 12V & 70V(Va) line from SMPS to X-BOARD.
No 12V supply to Top rightX-Board.
No Va(70V) supply to Top right X-Board.
Connect 12V line
Connect 70V line
LG Electronics / DND / QA Gr.
49/88
CheckCheck
The 3/5 top right of the screen is blank. (Top left X-BOARD)
Symptom Cause Countermeasure
No 12V supply to Top leftX-Board.
No Va(70V) supply to Top left X-Board.
Connect 12V line
Connect 70V line
Check Top left X-BOARD 12V.( If 0V, it happens )
Check Top left X-BOARD Va(70V).(If 0V, it happens)
Check 12V & Va(70V) line from SMPS to X-BOARD.
LG Electronics / DND / QA Gr.
50/88
CheckCheck
Pinkish screen in the 1/5 top right (Top left X-BOARD)
P1 COF connector on Top leftX-Board is open.
Reassemble it
Check the contact point and Locking of P1 on Top left X-BOARD.
Symptom Cause Countermeasure
LG Electronics / DND / QA Gr.
51/88
CheckCheck
The 3/5 bottom left of screen is broken. (BOTTOM RIGHT X-BOARD)
Symptom Cause Countermeasure
No 5V supply to bottom rightX-Board.
Connect 5V line
Check Bottom right X-BOARD 5V.( If 0V, it happens )
Check 5V line from SMPS to X-BOARD.
LG Electronics / DND / QA Gr.
52/88
CheckCheck
The 3/5 bottom left of the screen is Blank. (Bottom Right X-BOARD)
Symptom Cause Countermeasure
Check Bottom right X-BOARD 12V.( If 0V, it happens )
Check 12V line from SMPS to X-BOARD.
No 12V supply to bottom rightX-Board.
No Va(70V) supply to bottom right X-Board.
Connect 12V line
LG Electronics / DND / QA Gr.
53/88
CheckCheck
The 2/5 right of the screen is broken. (Bottom left X-BOARD)
Symptom Cause Countermeasure
Check Bottom left X-BOARD 5V.( If 0V, it happens )
Check 5V line from SMPS to X-BOARD.
No 5V supply to bottom leftX-Board.
Connect 5V line
LG Electronics / DND / QA Gr.
54/88
CheckCheck
The 2/5 right part of the screen is blank. (Bottom left X-BOARD )
No 12V supply to bottom leftX-Board.
Connect 12V line
Check Bottom left X-BOARD 12V.( If 0V, it happens )
Check 12V line from SMPS to X-BOARD.
Symptom Cause Countermeasure
LG Electronics / DND / QA Gr.
55/88
CheckCheck
ADDRESS bar appears in the right bottom of the screen. (X-BOARD BOTTOM LEFT)
The connecting of X-Board bottomleft connector is bad.
Reassemble it.
Check connecting of the connector of bottom left X-BOARD.
Reassemble it.
X-BOARD BOTTOM LEFT CONNECTOROPEN.
Symptom Cause Countermeasure
LG Electronics / DND / QA Gr.
56/88
Examples
LG Electronics / DND / QA Gr.
57/88
CheckCheck
Screen is divided in top and bottom, and vertical barappears.
Connector(P13) is OPEN or Connecting condition is bad
Reassemble P13.
P13 CONNECTOR contact point inferior CHECK.
P13 CONNECTOR SIGNAL CHEK.
P13 CONNECTOR
Symptom Cause Countermeasure
LG Electronics / DND / QA Gr.
58/88
CheckCheck
Screen is broken and has the vertical/horizontal bar.
VSC Board Connector is Open. Reassemble VSC BoardConnector
Check the connector connecting
Reassemble the Connector
Symptom Cause Countermeasure
LG Electronics / DND / QA Gr.
59/88
CheckCheck
The screen is bluish(Mosaic screen)
Loose VSC Board Connector Reassemble VSC BOARDConnector
Check the connection condition of the Connector.
Reassemble the Connector.
Symptom Cause Countermeasure
LG Electronics / DND / QA Gr.
60/88
CheckCheck
The mosaic appears in the screen when it connects to VIDEO Input.(The sensibility of Y-signal is low.)When connected to Component Input, it is O.K.
Bad IC203 Replace IC203(VPC3230D)
Check if X201 on VSC board oscillates.Check Video In/Out of IC203 on VSC board.
IC201(VPC3230D)Decoder IC
Symptom Cause Countermeasure
LG Electronics / DND / QA Gr.
61/88
IC201(VPC3230D) Decoder is inferior
Examples
LG Electronics / DND / QA Gr.
62/88
CheckCheck
Noise with division of colors
Bad Connector connectingControl Board and VSC B/D.
Contact point and signal condition of Connector Control Board and VSC Board.
Abnormal Normal
Bad Connector
SymptomCause
Countermeasure
Change the Connector
LG Electronics / DND / QA Gr.
63/88
Name No signal Vertical Bar
Symptom Cause and Countermeasure
Realization
1.Cause : Bad IC2 (DA1)
8cm
When ASIC Chip(IC2 DA1 LGD4001) on Control Board getshigh temperature, you can observe it(In normal temperature it’s O.K. )
IC2 DA1(Data Arrange) No.162 Pin output is changing depending on the temperature. abnormal X-B’d Buffer IC ⇒* Room temperature : 2.5V Output (Normal Pin = over 2.8V)* Heated : 1.5V Output(Normal Pin = 2.7V )
⇒ Bad IC2 (DA1)
< Waveform of normal pin>
heated
< Waveform of abnormal pin >
heated
DA1
Buffer
DA1
Buffer
Buffer(74ACT541) waveform abnormally narrows. →In this case, it is impossible for Flip Flop(74AC574) on X B/D to read data.
2. Countermeasure : Replace IC2
LG Electronics / DND / QA Gr.
64/88
Name Add Open (Green 1 Line)
Symptom Cause and Countermeasure
1.cause: Add. COF Drive IC inferior
Normal Line Data waveform Open Line Data output waveform
the output of inferior line less than that of the normal LineAdd. COF Drive IC inferior
COF inspection 검사기 : 24V Open check (normal 50V)
Add. COF Drive IC
LG Electronics / DND / QA Gr.
65/88
Name Vertical bar when Power off/on(Mis-discharge)
Symptom Cause and Countermeasure
Realization
1.PDP Power on Mode external input (regardless of wire/wireless signal but it’s easy to reenact in wireless signal)2. Remove Power Cord (Power’s off)3.after about 20minutes, insert Power cord (automatically the Power’s on and the vertical bar is shown as above)
1.Cause : Control board malfunctions when Power off/on.
2.Countermeasure: Change some parts on Control board.
3.Changing parts : A32_CTRL_03 B/D (Marked on PCB) -.R14,17,18,21 : 330 ==> 4.7K (Chip Resistor) -.R15,16,19,20 : 22K ==> 4.7K (Chip Resistor) -.C504, 505 : 0.1uF / 50V add (Chip Capacitor)
Control board
LG Electronics / DND / QA Gr.
66/88
X CANVAS X CANVAS
Normal
MODEL : MN-50PZ40S
Check Point : Cable & X-Board
Symptom : ADD Bar(No signal)
Action : Module Control Change
Bottom Center No Picture
50 Inch
LG Electronics / DND / QA Gr.
67/88
X CANVAS X CANVAS
Normal Bottom Center X-Board
MODEL : MN-50PZ40S
Check Point : X-Board (Bottom)
Symptom : ADD Bar
Action : X Board Change
LG Electronics / DND / QA Gr.
68/88
X CANVAS X CANVAS
Normal Horizontal Bar
Check Point : Y-Drive Board
Symptom : Horizontal Bar
Action : Y-Drive Board Change & Connector Clean
LG Electronics / DND / QA Gr.
69/88
++
DMM
TP5 GND
TP6 VA
VR8401
VA Adjust
VS AdjustVR8501 TP3
GNDTP4VS
PFC + PFC -
PFC PACK
VR801
1. PFC adjustment
-. Select 100% White Pattern signal and warm it up enough. -. Connect DMM with TP PFC+ and TP PFC – (GND). -. adjust VR801 to 380V (within ±1V ).
2. Va adjustment
When replacing PDP module & power board,Be sure to adjust Power Ass’y voltage.
380V ± 1V
-. Connect DMM + terminal with P814 #1 Pin.-. Turn VR8401 (Va Adj) to adjust the voltage on DMM to Va voltage value marked on panel bottom- right label. (allowable error : ±0.5V )
3. Vs adjustment-. Connect DMM’s + terminal with P803 # 9 Pin.-. Turn VR 8501 (Vs Adj )to adjust the voltage on DMM to Vs voltage value marked on panel bottom-right label.
Power PCB Voltage Adjustment
<SMPS Board>
60 Inch
LG Electronics / DND / QA Gr.
70/88
Power & no RasterPower & no Raster
AC input check (220V)AC input check (220V)
When Main S/W ON,ST-BY LED ON check (RED)
When Main S/W ON,ST-BY LED ON check (RED)
When SUB S/W on, LED GREEN checkWhen SUB S/W on, LED GREEN check
R8538, R8539,R8540OPEN check
R8538, R8539,R8540OPEN check
VS, VA PACK Function checkVS, VA PACK
Function check
each Connector & connection check
each Connector & connection check
Connection Plug with setConnection Plug with set
AC Line Fuse checkAC Line Fuse check
PFC Board R8301,R8302R8303 OPEN check
PFC Board R8301,R8302R8303 OPEN check
FAN function checkFAN function check
Controller BoardVS ON check
Controller BoardVS ON check
R8301,R8302,R8303 replacementR8301,R8302,R8303 replacement
5V MONI, 5V CTL output check5V MONI, 5V CTL output check
Controller Board replacementController Board replacement
Power Supply Section
LG Electronics / DND / QA Gr.
71/88
Connector between SP & set check
Connector between SP & set check IC601 (MSP3401) checkIC601 (MSP3401) check IC603 (LA4282) checkIC603 (LA4282) check Input jack check
(25Pin cable L,R input check)Input jack check
(25Pin cable L,R input check)
Sound power (P806A,B)Cable connection checkSound power (P806A,B)Cable connection check
Sound terminal Voltage check
(32V)
Sound terminal Voltage check
(32V)
F8811 Fuse Opencheck
F8811 Fuse Opencheck
Speaker connection line check
Speaker connection line check
Sound Section
LG Electronics / DND / QA Gr.
72/88
Abnormal screenAbnormal screen
PC signal inputPC signal input
IC406 ( ADV 7123 ) checkIC406 ( ADV 7123 ) check
IC404 ( FLI2220 ) checkIC404 ( FLI2220 ) check
IC403 ( FLI2220 )check IC403 ( FLI2220 )check
IC201 (VPC3230 ) checkIC201 (VPC3230 ) check
Input jack& Connector check
Input jack& Connector check
IC203 ( CXA2101 ) checkIC203 ( CXA2101 ) check
IC501 ( JAGASM check )IC501 ( JAGASM check )
IC901 (SII 150 ) check)IC901 (SII 150 ) check)
P901 ( 21 Pin cable ) checkP901 ( 21 Pin cable ) check
Video Signal Section
LG Electronics / DND / QA Gr.
73/88
X CANVAS
No power ( LED is not on in ST-BY) normal
CANVASX
AC power voltage checkAC power voltage check
Main Power S/W checkMain Power S/W check
F8301 Fuse (15A) checkF8301 Fuse (15A) check
F8302 Fuse checkF8302 Fuse check
F8301 Fuse (15A) replacementF8301 Fuse (15A) replacement
No power
LG Electronics / DND / QA Gr.
74/88
X CANVAS
Disappearing or error while watching
Intermittent image disappearing. LED’s greennormal
Cause : Y-Board VR301 waveform adjustment defect
Troubleshooting : Y-Board VR301 Adjust
See the next instruction(improved since Dec,2001)
Cause : Y-Board VR301 waveform adjustment defect
Troubleshooting : Y-Board VR301 Adjust
See the next instruction(improved since Dec,2001)
CANVASX
On-and-off
LG Electronics / DND / QA Gr.
75/88
X CANVAS
Automatic off as soon as power is on ( Protect )
Automatic off after 2~3 seconds ( Protect )normal
Cause : X-Board internal IC Short
Troubleshooting: replace the defective X-Board & DC-DC Board
*. Remove X – Board power supply connector to check whether power is off.
CANVASX
X - Board
Auto power off
LG Electronics / DND / QA Gr.
76/88
X CANVAS
Automatic off after 2 – 3 seconds ( Protect )normal
Cause : Y – Board 220V Line Short
Troubleshooting : Y – Board replacement
*. Remove Y – Board power supply connector to check Whether power is off.
CANVASX
Y - Board
Auto power off
Automatic off as soon as power is on ( Protect )
LG Electronics / DND / QA Gr.
77/88
X CANVAS X CANVAS
One horizontal line in the top part normal
Y-Board & Y-Drive Board Connector check Y-Board & Y-Drive Board Connector check
Y-Drive Board ( Top ) Drive IC checkY-Drive Board ( Top ) Drive IC check
Y-Drive Board replacementY-Drive Board replacement
Address Bar(Horizontal)
LG Electronics / DND / QA Gr.
78/88
X CANVAS X CANVAS
Single horizontal bar in the bottom
CANVASX
normal
Y-Board & Y-Drive Board Connector check Y-Board & Y-Drive Board Connector check
Y-Drive Board ( Bottom ) Drive IC checkY-Drive Board ( Bottom ) Drive IC check
Y-Drive Board replacementY-Drive Board replacement
Address Bar(Horizontal)
LG Electronics / DND / QA Gr.
79/88
X CANVAS X CANVAS
Image is on and off. LED’s green normal
Y-Board & Y-Drive Board Connector check Y-Board & Y-Drive Board Connector check
Y-Drive Board ( Top ) Drive IC checkY-Drive Board ( Top ) Drive IC check
Y-Drive Board replacementY-Drive Board replacement
Address Bar(Horizontal)
LG Electronics / DND / QA Gr.
80/88
X CANVAS X CANVAS
Green dot line on the screen normal
VSC Board & Controller Board Connector checkVSC Board & Controller Board Connector check
Controller Board checkController Board check
Controller Board replacementController Board replacement
Address Bar(Horizontal)
LG Electronics / DND / QA Gr.
81/88
X CANVAS X CANVAS
Address Bar. (Gray Pattern reception)
CANVASX
Address Bar. ( Red Pattern reception )
X-Board COF Drive IC checkX-Board COF Drive IC check
X-Board replacementX-Board replacement
X-Board Connector checkX-Board Connector check
Module ( Panel )replacementModule ( Panel )replacement
Address Bar(Vertical)
LG Electronics / DND / QA Gr.
82/88
X CANVAS X CANVAS
Intermittent image disappearing. LED is green image distorted (occurring twice a day)
normal
CANVASXX-Board COF Drive IC checkX-Board COF Drive IC check
X-Board replacementX-Board replacement
X-Board Connector checkX-Board Connector check
Module ( Panel )replacementModule ( Panel )replacement
Address Bar(Vertical)
LG Electronics / DND / QA Gr.
83/88
X CANVAS X CANVAS
X CANVAS
normal
Central top 4/10 of the screen with vertical bar Central top 4/10 of screen with no-picture
related X-Board power supply voltage checkrelated X-Board power supply voltage check
related X-Board Connector checkrelated X-Board Connector check
related X-Board & Controller Board Connector checkrelated X-Board & Controller Board Connector check
related X-Board replacementrelated X-Board replacement
Module (Panel ) checkModule (Panel ) check
Address Bar ( Vertical ) & partial no-picture
Address Bar(Vertical)
LG Electronics / DND / QA Gr.
84/88
X CANVAS X CANVAS
X CANVAS
normal
Bottom left 3/10 of the screen with no-pictureBottom left 3/10 of the screen with vertical bar
Address Bar ( Vertical ) & partial no-picture
Related X-Board power supply voltage checkRelated X-Board power supply voltage check
Related X-Board Connector checkRelated X-Board Connector check
Related X-Board & Controller Board Connector checkRelated X-Board & Controller Board Connector check
Related X-Board replacementRelated X-Board replacement
Module (Panel ) checkModule (Panel ) check
Address Bar(Vertical)
LG Electronics / DND / QA Gr.
85/88
X CANVAS X CANVAS
X CANVAS
normal
Bottom right 3/10 of the screen with vertical bar Bottom right 3/10 of the screen with no-picture
related X-Board power supply voltage checkrelated X-Board power supply voltage check
Related X-Board Connector checkRelated X-Board Connector check
Related X-Board & Controller Board Connector checkRelated X-Board & Controller Board Connector check
Related X-Board replacementRelated X-Board replacement
Module (Panel ) checkModule (Panel ) check
Address Bar ( Vertical ) & partial no-picture
Address Bar(Vertical)
LG Electronics / DND / QA Gr.
86/88
X CANVAS X CANVAS
X CANVAS
normal
Central bottom 4/10 of the screen with vertical bar Central bottom 4/10 of the screen with no-picture
Related X-Board power supply voltage checkRelated X-Board power supply voltage check
Related X-Board Connector checkRelated X-Board Connector check
Related X-Board & Controller Board Connector checkRelated X-Board & Controller Board Connector check
Related X-Board replacementRelated X-Board replacement
Module (Panel ) checkModule (Panel ) check
Address Bar ( Vertical ) & partial no-picture
Address Bar(Vertical)
LG Electronics / DND / QA Gr.
87/88
X CANVAS CANVASX
normal
CANVASX
Top right 3/10 of the screen with vertical bar Top right 3/10 of the screen with no-picture
Related X-Board power supply voltage checkRelated X-Board power supply voltage check
Related X-Board Connector checkRelated X-Board Connector check
Related X-Board & Controller Board Connector checkRelated X-Board & Controller Board Connector check
Related X-Board replacementRelated X-Board replacement
Module (Panel ) checkModule (Panel ) check
Address Bar ( Vertical ) & partial no-picture
Address Bar(Vertical)
LG Electronics / DND / QA Gr.
88/88
X CANVAS
Top left 3/10 of the screen with vertical bar
CANVASX
normal
CANVASX
Top left 3/10 of the screen with no-picture
Related X-Board power supply voltage checkRelated X-Board power supply voltage check
Related X-Board Connector checkRelated X-Board Connector check
Related X-Board & Controller Board Connector checkRelated X-Board & Controller Board Connector check
Related X-Board replacementRelated X-Board replacement
Module (Panel ) checkModule (Panel ) check
Address Bar ( Vertical ) & partial no-picture
Address Bar(Vertical)
LG Electronics / DND / QA Gr.