Transcript
PDP One Point Repair Guide 1. 1. General General 2. 40 ~ 50 50 Inch Inc Inch Practice Pra Pract ctic ice e 3. 3. 60 60 Inch Inch Practice Pra Prac ctice
Symptom
Cause
Countermeasure
(Bad X-Board PCB)
Change X board
PCB Pattern Short
Red Bar at left lower
CHECK Point
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
*FPC : Flat Pin Connector
2/88
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Symptom
Cause
Countermeasure
(Bad X-Board PCB)
Change X board
PCB Pattern Short
Red Bar at left lower
CHECK Point
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
*FPC : Flat Pin Connector
2/88
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Symptom
Cause
PCB
G
Countermeasure
R
Red
& Green pin of left lower 4th FPC short Change X-Board Defect Point Point : Short on the PCB just above above connector
1. Cause : Short by solder bridge - Can not not observe with with naked eye eye - When connector connector open, open, pattern is is OK
Check 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, connectors, IC output stage and PCB pattern. 4. If no problem, check the connector lead board.
3/88
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Symptom
Cause
Pattern Short by connector miss insert
Countermeasure
Re-insert the Connector
Bottom Right 6th FPC R/B Short
Check 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 connectors,, IC output output stage stag e and PCB pattern. 4. If no problem, check the connector lead board.
4/88
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Symptom
Countermeasure
Cause
SHORT Foreign Material(Iron powder) in the Connector
X-Board Tape Rework
Gap
Insulation tape
ADD
Electrode short at R,G,B Raster or White Screen(Different color display)
Apply silicon on the Connector lead
Pay attention to a capillary symptom
Check Point
1. Trace defected line 2. Check the condition of FPC and connector on the X-Board, IC Output stage and Electrode line.
5/88
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Symptom
Countermeasure
Cause
Keep horizontal, or can be defected
FPC connector Rework
OPEN
Interfere with mechanical structure when Module assembling Cold soldering at Connector 1. Outbreak during heat run 2. ADD Electrode open at one color Raster or White screen(No discharge)
Use Connector fixing iron plate
Keep the contact point horizontal when interfere with mechanical parts
Check Point
1. Trace defected line and check the condition of FPC and connector on X-Board, IC Output stage and Electrode line.
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Symptom
Countermeasure
Cause
Replace the Panel
ADD Pattern
Connected minutely and open slowly as time passes
ADD open
Check Point
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
7/88
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Symptom & Cause
Countermeasure
~ ADD Electrode open
at Green
Panel Electrode
Raster
Replace the Panel
Open Electrode(16) 1. ADD pattern of P AD siden open 2. Width : 10 um
~
Resistance A
Resistance
16pin
1.2
6.0
1,3,15,17,19pin
1.0 ~1.2
2.2~2.4
B
Resistance
ACF
B
FPC Electrode Resistance A
Check Point
1. Check the connection condition - Press the connector and reconnect 2. Check the soldering condition of Connector lead 3. 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
8/88
* The difference of ADD open and Short ? ADD open : Black vertical bar at Raster ADD short : Different color vertical bar at Raster
LG Electronics / DND / QA Gr.
Symptom
Countermeasure
Cause Control board
Con 1
Con 2
Change Control Board
X-board
< Raster >
< White > Solder bridge
ADD short at raster screen and ADD open at white screen appear at some area after 20 minute HeatRun.
Check Point
1. Check the 5V(Logic voltage) input to DC-DC If it is lower than 5V, it makes similar problem 2. 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
9/88
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Symptom
Countermeasure
Cause
Change X-BOARD X-DRV IC CLK LE
PCB pattern short
Short
R264 R258 U1
SN74 ACT541
Check Point
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
10/88
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Symptom
Countermeasure
Cause
connector Chip Resistors
4X16 = 64 data
Electrode Pattern
1
X driver chip (SN755851PJ)
M o d u l e
Change X Board
64 16 clock line1 line2
PCB pattern is connected minutely
Foreign material when photo resisting
line3 line4
Check Point
1. Check the connection condition of the Connector. 2. Check the cold soldering.
11/88
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Symptom
Countermeasure
Cause
Resistance
between 186 pin of U3 and 7 pin of U300 is 62 Normal condition : 2 Change Control Board
Because of foreign material in Via hole at U300 side Via hole U3 ALTERA
Vertical bar in every 20mm
Chip
186pin PIN
U300 DRAM
7pin PIN
Control board
Check Point
1. Measure the resistance of Via holes between that of normal.(Normal : 2~3 ) 2. Resistance increases as temperature rises.
U3
and
U300
at Control Board and compare with
12/88
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Symptom
Cause
Countermeasure
- Open circuit between pin 7 of U200 and pin 7 of U7 Replace Control Board - Resistance between two pins varies from 19 ohm ~ 45Kohm
Check Point
1. Observe the symptom during Heat- Run at 45 degree. 2. Check the resistance of VI A holes of suspect ICs
13/88
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Symptom
Cause
- When Power On, Fan operates but No OSD displays - LED(D3) of Control Board doesn¶t operate D1
D3
D4
PROM(U40)
1. Because Control data on P ROM(U40) doesn¶t download to FPG A, it can¶t generate control signal to X,Y and Z Board. 2. Defected ALTERA.
Countermeasure
Replace Control Board Replace PROM
FPG A * For normal operation, PROM program should be downloaded to FPG A, and each P ROM has correspondent FPG A. See left picture.
CONTROL BOARD
Check Point
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
14/88
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Symptom
Cause
Countermeasure
Control Board
Replace Controller board
Touch point(M arked)
No signal or at PC mode, dark red raster displays. This is darker than normal Red signal.
Neighboring Pins of U1(FPG A)
touch
Check Point
- TV VSC board - Board connector(50 pin) contact point - Control board of Module
15/88
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Symptoms
Countermeasure
Cause 1. CN1 on Vs Board cold soldering 2. Spark marks between CN1 and Vs Board -> It m akes them open
Replace DC-DC 2 board Soldering Direction Soldering point
CN1 Vs board
1. No Raster(ST-BY LED On) 2. Spark noise(Tik-Tik) 3. No Vs, Vsetup & Vsc
Solder land
Solder Soldering Direction
Check Point
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, T R, Diode and Resistor(especially Cement Resistor) 4. Observe PCB Pattern and soldering condition with naked eyes
16/88
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40 ~ 42 Inch 42´ PDP Flicker and
42 Inch
No Raster Troubleshooting Guide cause : bad connection between Y-Board # 1, 2 drive board Connector pin
P6 Rework should be done P4 Y-Driver Board
Y-Board
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P4
P6
amplified
amplified : outside Leg : inside Leg 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.
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Be sure not to misconnect the line. See the picture precisely and then connect jump wire at the exact point
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Intermittent no-image/image error X CANVAS
while watching
X CANVAS
The screen is intermittently disappeared . LED is green
screen is distorted weiderly (happened 2 a day)
X CANVAS 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) normal 20/88
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No Power X CANVAS
X CANVAS
No Power ( in ST-BY mode , but no LED)
normal
Check the power supply & main power S/W on Check EMI board fuse (check the rated capacity )
Be sure to use rated fuse. Fuse 15 A
21/88
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No Raster X CANVAS
X CANVAS
when Power¶s on, after 2 ~ 3 sec, it¶s off ( LED changing green into red )
normal
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.
22/88
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No Picture X CANVAS
X CANVAS
no picture (LED¶s green)
normal
Core checkpoint : remove STB and operate monitor individually. (check whether STB¶s a defect or monitor ¶s one) With monitor defect , check VSC and then Controller Board. Troubleshooting : replace VSC Board
23/88
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Address Bar ( Horizontal Bar ) X CANVAS
X CANVAS
no image (LED¶s green)
normal
Cause : Y-Drive ( Bottom ) defect Troubleshooting : Y-Drive (lower part) replacement This problem is shown in the bottom of screen , So it is caused by Y-Drive
Y-Drive Board ( Bottom ) 24/88
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Address Bar ( Horizontal Bar ) X CANVAS
X CANVAS
no image (LED¶s green)
normal
Y-Drive Board ( Top ) Cause : Y-Drive Board (upper part) defect Troubleshooting : Y-Drive Board replacement
25/88
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No Picture X CANVAS
X CANVAS
no image (LED¶s green)
normal PD501 Connector
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)
26/88
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High frequency noise ( ³Bee´ sound) X CANVAS
X CANVAS
normal
normal picture with high frequency noise (³bee´) SMPS is supposed to operate with high frequency so small noise is not considered as a defect. Power (SMPS) Board 1. C8178 0.22/50V add 2. Open C8139 right lead,
and then connect it to R8164 right lead. Improved since Nov,2001
C8178 0.22uF electrolytic capacitor insertion
Open C8139 right lead and then wire R8164 right lead
#. Slight noise is not a defect and write down explanation 27/88
LG Electronics / DND / QA Gr.
No picture in right- 2/5 area X CANVAS
No picture in the right- 2/5
X CANVAS
normal
area
X-Board ( Left ) power supply check X-Board ( Left )Connector check X-Board ( Left ) replacement
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Address Bar (Vertical ) X CANVAS
X CANVAS
normal
stripe in right-2/ 5 area X-Board ( Left ) power supply check X-Board ( Left ) Connector check X-Board ( Left ) replacement
29/88
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No picture in left 3/5 of the screen X CANVAS
X CANVAS
normal
left 3/5 of screen with vertical stripes
X-Board ( Right ) power supply check X-Board ( Right )Connector check X-Board ( Right ) replacement
30/88
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Address Bar (Vertical ) X CANVAS
X CANVAS
normal
left 3/5 of screen with vertical stripes.
X-Board ( Right ) power supply check X-Board ( Right )Connector check X-Board ( Right ) replacement
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No Red X CANVAS
X CANVAS
no Red ( B or G )
normal
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
Be sure not to bend it by force or internal Insulated conductor can be down.
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1) X - Board COF Connector separation Lift up the right and left of X-BO ARD CONNECTOR.
42 Inch Lift up X-BO ARD CONNECTOR and separate COP CONNECTOR by pulling up.
When you handle COF CONNECTO R, don¶t pressure. First release LOCK and separate. If COF CONNECTOR is damaged, you should replace MOD ULE ASS¶Y. So, be aware of this!!
COF Connector
Warning 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.
33/88
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2) X - Board Connector separation
Lift up each edge of left/right.
Lifted condition Be careful to handle LOCK or it can be broken. When LOCK is broken, replace a new X-BO ARD.
Warning
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-BO ARD
34/88
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3) Y - Board COF Connector separation
Pull the white LOCK as shown in arrow
Pull the white LOCK as shown in arrow.
Separate COF CONNECTO R by pulling in the left.
Warning
Be careful to handle LOCK and COF Connector. When LOCK part is damaged, you should replace a new Y-Board. In case of COF Connector, Module Assembly.
35/88
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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
Warning
Be careful not to tear COF Connector. If COF Connector is torn, replace a new Module Assembly
36/88
Pull COF Connector as shown in arrow.
It¶s easy to separate COF on condition that Z-Board Screw is separated. COF Connector In case Z-Board is assembled, it¶s really hard to separate.
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5) Connector separation Guide Push LOCK and pull out
PUSH
PUSH
PUSH
PUSH
PUSH
37/88
PULL
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6) Control Board & VSC Board Connector
38/88
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7)
Gas injection (Sealing up) condition
Be sealed up after gas injection
Be sealed up after gas injection
Warning
Be careful to handle the sealed-up part after gas injection. If it is broken, the gas escapes. So, replace the Module.
39/88
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8) Power off in 2 ~ 3 minutes(Protection) Power is On and off 2~3 2~3 minutes. (Protection) P301 01 Connector Connector Open Open Check. Check.
OK
X - Board Board Top op Right Righ Right Change. Chang Change. e. OK
P302 02 Connector Connector Open Open Ch C Check heck
X - Board Board Top op Left Le Left ft Change. Chang Ch C hange. e.
OK
P303 Connector Open Check
P304 Connector Open Check
X - Board Bottom Right Change. Change.
OK
P102 Connector Open Check
X - Board Bottom Left Change. Change. OK
P3, P2 Connector Open Check
Z - Board Change. Change. OK
P005, P003 P003 Connector Open Check PROTECT operation;
P006 Connector Open Check
When the load voltage voltage is short. When each voltage doesn¶t work (in general) general)
Y - Board Change. Change.
OK
VSC- Board Change. Change.
OK
VSC - Board Change. Change. Sound Output IC Short Check
Power Board Change
40/88
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9)
Power off in 2 ~ 3 minutes(Protection)
L813 Cold Solder
Symptom : As soon as the power on, it¶s off in 2 - 3minutes. (PROTECT operation) Cause : No VS voltage L813 Coil cold soldering.
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.
41/88
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10) ADD BAR inspection and repair
Press the ADJ KEY and check the position of add bar by changing WHITE or RED or BLUE or GREEN
HEATRUN : WHITE
Top Right
Bottom Right
Top Left
Bottom Left
MP-40P A10 uses 4 board such as left,right, top and bottom. Divide the screen in 4 and once you see ADD B AR check COF CONNECTOR between MODULE and X-BO ARD. If there is no defect in COF CONNECTO R replace X-BO ARD. But the problem still remains and check the connector between X-BO ARD and CONTROL BO ARD. And if you can¶t find defect, check CONT ROL.
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11) One Point Service Guide
Symptom : B color 1 Address line Open Cause : Dented COF
COF is dented
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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
44/88
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Symptom
Causes
If 15V line voltage reduces below 14V, Mis-discharge occurs and power off because of protection circuit.
Countermeasure
Replace PSU (Power Supply Unit) and defective X-Board.
Defective X-Board
The blue spreads on the screen (Mis-discharge) and power off in 2 ~ 3 seconds. If you turn on again, it w ill be same problem.
Check If when Power on, screen shows like above and turn off in 2 seconds, check if turning off or not by disconnecting all X & Y boards.
45/88
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Symptom
Cause
No 5V supply to Top right X-Board.
Countermeasure
Connect 5V line
The top left part of screen is broken (Top Right X-BOARD)
Check Check Top right X-BOARD 5V.(If 0V, it happens) Check 5V line from SMPS to X-BOARD.
46/88
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Cause
Symptom
No Va(70V) supply to Top right X-Board.
Countermeasure
Connect 70V line
Pinkish screen in the top left. (Top right X-BOARD)
Check Check Top right X-BOARD Va(70V).(If 0V, it happens) Check 70V(Va) line from SMPS to X-BOARD.
47/88
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Symptom
Cause
Countermeasure
No 12V supply to Top right X-Board.
Connect 12V line
No Va(70V) supply to Top right X-Board.
Connect 70V line
The 3 /5 top left in t he screen is blank (Top Right X-BOARD) Check 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.
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Cause
Symptom
Countermeasure
No 12V supply to Top left X-Board.
Connect 12V line
No Va(70V) supply to Top left X-Board.
Connect 70V line
The 3 /5 top right of t he screen is blank. (Top left X-BOARD)
Check 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.
49/88
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Cause
Countermeasure
P1 COF connector on Top left X-Board is open.
Reassemble it
Symptom
Pinkish screen in the 1/5 top right (Top left X-BOARD)
Check Check the contact point and Locking of P1 on Top left X-BOARD.
50/88
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Symptom
Cause
No 5V supply to bottom right X-Board.
Countermeasure
Connect 5V line
The 3 /5 bottom left of screen is br oken. (BOTTOM RIGHT X-BOARD)
Check Check Bottom right X-BOARD 5V.( If 0V, it happens ) Check 5V line from SMPS to X-BOARD.
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Cause
Symptom
No 12V supply to bottom right X-Board.
Countermeasure
Connect 12V line
No Va(70V) supply to bottom right X-Board.
The 3 /5 bottom left of the screen i s Blank. (Bottom Right X-BOARD)
Check Check Bottom right X-BOARD 12V.( If 0V, it happens ) Check 12V line from SMPS to X-BOARD.
52/88
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Symptom
Cause
No 5V supply to bottom left X-Board.
Countermeasure
Connect 5V line
The 2/5 right of the screen is broken. (Bottom left X-BOARD)
Check Check Bottom left X-BOARD 5V.( If 0V, it happens ) Check 5V line from SMPS to X-BOARD.
53/88
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Cause
Countermeasure
No 12V supply to bottom left X-Board.
Connect 12V line
Symptom
The 2/5 right part of the screen is blank. (Bottom left X-BOARD )
Check Check Bottom left X-BOARD 12V.( If 0V, it happens ) Check 12V line from SMPS to X-BOARD.
54/88
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Cause
Countermeasure
The connecting of X-Board bottom left connector is bad.
Reassemble it.
Symptom
ADDRESS bar appears in the right bottom of the screen. (X-BOARD BOTTOM LEFT)
Check Check connecting of the connector of bottom left X-BOARD. Reassemble it. X-BOARD BOTTOM LEFT CONNECTOR OPEN.
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Examples
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Symptom
Cause
Connector(P13) is OPEN or Connecting condition is bad
Countermeasure
Reassemble P13.
Screen is divided in top and bottom, and vertical bar appears.
Check
P13 CONNECTOR contact point inferior CHECK. P13 CONNECTOR SIGNAL CHEK.
P13 CONNECTOR
57/88
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Symptom
Cause
Countermeasure
VSC Board Connector is Open.
Reassemble VSC Board Connector
Screen is broken and has the vertical/horizontal bar.
Check Check the connector connecting Reassemble the Connector
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Symptom
Cause
Loose VSC Board Connector
Countermeasure
Reassemble VSC BOARD Connector
The screen is bluish(Mosaic screen)
Check Check the connection condition of the Connector. Reassemble the Connector.
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Symptom
Cause
Countermeasure
Bad IC203
Replace IC203(VPC3230D)
The mosaic appears in the screen when it connects to VI DEO Input. (The sensibility of Y-signal is low.) When connected to Component Input, it is O.K.
Check
Check if X201 on VSC board oscillates. Check Video In/Out of IC203 on VSC board. IC201 (VPC3230D) Decoder IC
60/88
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Examples
IC201(VPC3230D) Decoder is inferior 61/88
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Cause Countermeasure
Symptom
Bad Connector connecting Control Board and VSC B/D.
Change the Connector
Abnormal
Normal
Noise with division of colors
Check Contact point and signal condition of Connector Control Board and VSC Board.
Bad Connector
62/88
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Name
No signal Vertical Bar Symptom
Cause and Countermeasure 1.Cause : Bad IC2 (D A1) IC2 D A1(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)
2. Countermeasure :
Replace
IC2
< Waveform of normal pin>
heated
< Waveform of abnormal
pin > heated
8cm
Realization
DA1
DA1
Buffer
Buffer
When ASIC Chip(IC2 D A1 LGD4001) on Control Board gets high temperature, you can observe it (In normal temperature it¶s O.K. ) Buffer(74ACT541) waveform abnormally narrows. In this case, it is impossible for Flip Flop( 74AC574) on X B/D to read data.
63/88
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Name
Add
Open (Green 1 Line) Symptom
Cause and Countermeasure 1.cause: Add. COF Drive IC inferior
Add.
Normal Line Data waveform
COF Drive IC
Open Line Data output waveform
the output of inferior line less than that of the normal Line Add.
COF Drive IC inferior
COF inspection : 24V Open check (normal 50V)
64/88
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Name
Vertical bar when Power off/on(Mis-discharge) Symptom
Cause and Countermeasure 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
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 i s shown as above)
65/88
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50 Inch
X CANVAS
X CANVAS
Bottom Center No Picture
Normal
MODEL : MN-50PZ40S Check Point :
Cable & X-Board
Symptom : ADD Bar(No signal)
Action : Module Control Change
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X CANVAS
X CANVAS
Bottom Center X-Board
Normal
MODEL : MN-50PZ40S Check Point :
X-Board (Bottom)
Symptom : ADD Bar Action : X Board Change
67/88
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X CANVAS
X CANVAS
Horizontal Bar
Normal
Check Point : Y-Drive Board Symptom : Horizontal Bar Action : Y-Drive Board Change & Connector Clean
68/88
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60 Inch
Power PCB Voltage Adjustment TP5 GND
VA Adjust
When replacing PDP module & power board, Be sure to adjust Power Ass¶y voltage.
TP6 VA
VR8401
VS Adjust VR8501 TP3 GND
TP4 VS
DMM +
PFC +
1. PFC adjustment
PFC -
-. 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 ).
380V ± 1V VR801
2. Va adjustment -. Connect DMM + terminal with P814 #1 Pin. -. Turn V R8401 (Va Adj) to adjust the voltage on DMM to Va voltage value marked on panel bottom- right label. (allowable error : ±0.5V )
PFC PACK
3. Vs adjustment -. Connect DMM¶s + terminal with P803 # 9 Pin. -. Turn V R 8501 (Vs Adj )to adjust the voltage on DMM to Vs voltage value marked on p anel bottom-right label. 69/88
LG Electronics / DND / QA Gr.
Power Supply Section
Power & no Raster
AC input check (220V)
Connection Plug with set
When Main S/W ON, ST-BY LED ON check (RED)
AC Line Fuse check
When SUB S/W on, LED GREEN check
PFC Board R8301,R8302 R8303 OPEN check
R8301,R8302,R8303 replacement
R8538, R8539,R8540 OPEN check
FAN function check
5V MONI, 5V CTL output check
VS, VA PACK Function check
Controller Board VS ON check
Controller Board replacement
each Connector & connection check
70/88
LG Electronics / DND / QA Gr.
Sound Section
Connector between SP & set check
Sound power (P806A,B) Cable connection check
IC601 (MSP3401) check
IC603 (LA4282) check
Sound terminal Voltage check (32V)
F8811 Fuse Open check
71/88
Input jack check (25Pin cable L,R input check)
Speaker connection line check
LG Electronics / DND / QA Gr.
Video Signal Section Abnormal screen
PC signal input
IC501 ( JAGASM check )
IC203 ( CXA2101 ) check
IC901 (SII 150 ) check)
IC406 ( ADV 7123 ) check
P901 ( 21 Pin cable ) check
IC404 ( FLI2220 ) check
IC403 ( FLI2220 )check
IC201 (VPC3230 ) check
Input jack & Connector check 72/88
LG Electronics / DND / QA Gr.
No power X CANVAS
X CANVAS
normal
No power ( LED is not on in ST-BY)
AC power voltage check
Main Power S/W check
F8301 Fuse (15A) check F8301 Fuse (15A) replacement F8302 Fuse check
73/88
LG Electronics / DND / QA Gr.
On-and-off Disappearing or error while watching X CANVAS
X CANVAS
normal
Intermittent image disappearing. LED ¶s green
Cause : Y-Board VR 301 waveform adjustment defect Troubleshooting : Y-Board VR301 Adjust
See the next instruction(improved since Dec,2001)
74/88
LG Electronics / DND / QA Gr.
Auto power off Automatic off as soon as power is on ( Protect ) X CANVAS
X CANVAS
normal
Automatic off after 2~3 seconds ( Protect )
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.
X - Board
75/88
LG Electronics / DND / QA Gr.
Auto power off Automatic off as soon as power is on ( Protect ) X CANVAS
X CANVAS
Automatic off after 2
Cause : Y
±
±
normal
3 seconds ( Protect )
Board 220V Line Short
Troubleshooting : Y
±
Board replacement
*. Remove Y ± Board power supply connector to check Whether power is off.
76/88
Y - Board LG Electronics / DND / QA Gr.
Address Bar(Horizontal) X CANVAS
X CANVAS
One horizontal line in the top part
normal
Y-Board & Y-Drive Board Connector check
Y-Drive Board ( Top ) Drive IC check
Y-Drive Board replacement
77/88
LG Electronics / DND / QA Gr.
Address Bar(Horizontal) X CANVAS
X CANVAS
normal
Single horizontal bar in the bottom
X CANVAS Y-Board & Y-Drive Board Connector check
Y-Drive Board ( Bottom ) Drive IC check
Y-Drive Board replacement
78/88
LG Electronics / DND / QA Gr.
Address Bar(Horizontal) X CANVAS
X CANVAS
normal
Image is on and off. LED¶s green
Y-Board & Y-Drive Board Connector check
Y-Drive Board ( Top ) Drive IC check
Y-Drive Board replacement
79/88
LG Electronics / DND / QA Gr.
Address Bar(Horizontal) X CANVAS
X CANVAS
normal
Green dot line on the screen
VSC Board & Controller Board Connector check
Controller Board check
Controller Board replacement
80/88
LG Electronics / DND / QA Gr.
Address Bar(Vertical) X CANVAS
X CANVAS
Address Bar. ( Red Pattern reception )
Address Bar. (Gray Pattern reception)
X CANVAS
X-Board COF Drive IC check
X-Board Connector check X-Board replacement
Module ( Panel )replacement
81/88
LG Electronics / DND / QA Gr.
Address Bar(Vertical) X CANVAS
X CANVAS
Intermittent image disappearing. LED is green
image distorted (occurring twice a day)
X CANVAS
X-Board COF Drive IC check
X-Board Connector check X-Board replacement
Module ( Panel )replacement
normal 82/88
LG Electronics / DND / QA Gr.
Address Bar(Vertical) Address Bar ( Vertical ) & partial no-picture X CANVAS
X CANVAS
Central top 4 /10 of the screen with vertical bar
Central top 4 /10 of screen with no-picture
X CANVAS
related X-Board power supply voltage check
related X-Board Connector check
related X-Board & Controller Board Connector check
related X-Board replacement
normal
Module (Panel ) check
83/88
LG Electronics / DND / QA Gr.
Address Bar(Vertical) Address Bar ( Vertical ) & partial no-picture X CANVAS
X CANVAS
Bottom left 3 /10 of the screen wit h vertical bar
Bottom left 3 /10 of the screen with no-picture
Related X-Board power supply volt age check
X CANVAS
Related X-Board Connector check
Related X-Board & Controller Board Connector check
Related X-Board replacement
Module (Panel ) check
normal 84/88
LG Electronics / DND / QA Gr.
Address Bar(Vertical) Address Bar ( Vertical ) & partial no-picture X CANVAS
X CANVAS
Bottom right 3 /10 of the screen with no-picture
Bottom right 3 /10 of the screen with vertical bar
X CANVAS
related X-Board power supply voltage check
Related X-Board Connector check
Related X-Board & Controller Board Connector check
Related X-Board replacement
normal
Module (Panel ) check
85/88
LG Electronics / DND / QA Gr.
Address Bar(Vertical) Address Bar ( Vertical ) & partial no-picture X CANVAS
X CANVAS
Central bottom 4 /10 of the screen wit h vertical bar
Central bottom 4 /10 of the screen with no-picture
X CANVAS
Related X-Board power supply voltage check Related X-Board Connector check
Related X-Board & Controller Board Connector check Related X-Board replacement
Module (Panel ) check
normal 86/88
LG Electronics / DND / QA Gr.
Address Bar(Vertical) Address Bar ( Vertical ) & partial no-picture X CANVAS
X CANVAS
Top right 3/10 of the screen with vertical bar
Top right 3/10 of the screen with no-picture
X CANVAS
Related X-Board power supply voltage check Related X-Board Connector check
Related X-Board & Controller Board Connector check Related X-Board replacement
normal
Module (Panel ) check 87/88
LG Electronics / DND / QA Gr.
