Panasonic TH-L42S25S User manual

© Panasonic Corporation 2010. Unauthorized
copying and distribution is a violation of law.
ORDER NO. MTV1002004CE
LCD TV
Model No. TH-L42S25S
Chassis: LA02
Destination: INDONESIA
TABLE OF CONTENTS
PAGE PAGE
1 Safety Precautions----------------------------------------------- 3
1.1. General Guidelines---------------------------------------- 3
1.1.1. Leakage Current Cold Check---------------------- 3
1.1.2. Leakage Current Hot Check (See Figure
1.) --------------------------------------------------------- 3
2 Warning -------------------------------------------------------------- 4
2.1. Prevention of Electrostatic Discharge (ESD)
to Electrostatically Sensitive (ES) Devices---------- 4
2.2. About lead free solder (PbF)---------------------------- 5
3 Service Navigation ----------------------------------------------- 6
3.1. Service Hint ------------------------------------------------- 6
4 Specifications ----------------------------------------------------- 7
5 Service Mode ------------------------------------------------------ 9
5.1. How to enter into Service Mode ----------------------- 9
5.1.1. Contents of adjustment mode --------------------- 9
5.1.2. How to exit---------------------------------------------- 9
5.2. SRV-TOOL -------------------------------------------------10
5.2.1. How to access ----------------------------------------10
5.2.2. Display of SOS History -----------------------------10
5.2.3. POWER ON TIME/COUNT----------------------- 10
5.2.4. Exit ------------------------------------------------------ 10
5.3. Service Mode Adjustment------------------------------ 11
5.3.1. Self Check Mode ------------------------------------ 11
5.3.2. Hotel Mode Adjustment---------------------------- 11
5.3.3. Hotel Mode-------------------------------------------- 11
6 Troubleshooting Guide --------------------------------------- 12
6.1. Check of the IIC bus lines------------------------------ 12
6.1.1. How to access --------------------------------------- 12
6.1.2. Exit ------------------------------------------------------ 12
6.1.3. Screen display --------------------------------------- 12
6.1.4. Check Point ------------------------------------------- 12
6.2. Power LED Blinking timing chart --------------------- 13
6.3. No Power--------------------------------------------------- 13
7 Disassembly and Assembly Instructions--------------- 14
7.1. AC Cord Dressing---------------------------------------- 14
7.2. AC Cord Installation ------------------------------------- 15
7.3. Control Panel Fitting------------------------------------- 16
7.4. Side AV Bracket Preparation-------------------------- 17

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7.5. Speaker Preparation and Installation---------------- 18
7.6. LCD Panel Fixing & Handling Method -------------- 19
7.7. LED Panel Installation ---------------------------------- 20
7.8. Mask Bracket Installation------------------------------- 21
7.9. Top and Bottom MTG Installation -------------------- 22
7.10. Metal Bracket Left Installation------------------------- 23
7.11. Vertical Metal Bracket Install -------------------------- 24
7.12. Barrier Fitting ---------------------------------------------- 25
7.13. LVDS Metal Installation --------------------------------- 26
7.14. Chassis Frame Installation----------------------------- 27
7.15. Screw PCB and Clamper Fitting --------------------- 28
7.16. Wire Install ------------------------------------------------- 29
7.17. Rubber Heat Sticking------------------------------------ 30
7.18. Pet AL+Tape Install -------------------------------------- 31
7.19. Pedestal Assembly -------------------------------------- 32
8 Measurements and Adjustments -------------------------- 34
8.1. Power Supply to Check A-Board--------------------- 34
8.2. Target of WB adjustment value ----------------------- 34
9 Block Diagram --------------------------------------------------- 35
9.1. Main Block Diagram ------------------------------------- 35
9.2. Detailed Block Diagram (1/3)-------------------------- 36
9.3. Detailed Block Diagram (2/3)-------------------------- 37
9.4. Detailed Block Diagram (3/3)-------------------------- 38
10 Wiring Connection Diagram --------------------------------- 39
10.1. Wire Dressing --------------------------------------------- 39
11 Schematic Diagram--------------------------------------------- 40
11.1. Schematic Diagram Notes ----------------------------- 40
11.2. A-Board (1/19) Schematic Diagram ----------------- 41
11.3. A-Board (2/19) Schematic Diagram ----------------- 42
11.4. A-Board (3/19) Schematic Diagram ----------------- 43
11.5. A-Board (4/19) Schematic Diagram ----------------- 44
11.6. A-Board (5/19) Schematic Diagram ----------------- 45
11.7. A-Board (6/19) Schematic Diagram ----------------- 46
11.8. A-Board (7/19) Schematic Diagram ----------------- 47
11.9. A-Board (8/19) Schematic Diagram ----------------- 48
11.10. A-Board (9/19) Schematic Diagram ----------------- 49
11.11. A-Board (10/19) Schematic Diagram --------------- 50
11.12. A-Board (11/19) Schematic Diagram---------------- 51
11.13. A-Board (12/19) Schematic Diagram --------------- 52
11.14. A-Board (13/19) Schematic Diagram --------------- 53
11.15. A-Board (14/19) Schematic Diagram --------------- 54
11.16. A-Board (15/19) Schematic Diagram --------------- 55
11.17. A-Board (16/19) Schematic Diagram --------------- 56
11.18. A-Board (17/19) Schematic Diagram --------------- 57
11.19. A-Board (18/19) Schematic Diagram --------------- 58
11.20. A-Board (19/19) Schematic Diagram --------------- 59
11.21. K-Board Schematic Diagram -------------------------- 60
11.22. P-Board Schematic Diagram -------------------------- 61
11.23. TC-Board (1/6) Schematic Diagram----------------- 62
11.24. TC-Board (2/6) Schematic Diagram----------------- 63
11.25. TC-Board (3/6) Schematic Diagram----------------- 64
11.26. TC-Board (4/6) Schematic Diagram----------------- 65
11.27. TC-Board (5/6) Schematic Diagram----------------- 66
11.28. TC-Board (6/6) Schematic Diagram----------------- 67
11.29. V-Board Schematic Diagram -------------------------- 68
12 Printed Circuit Board ------------------------------------------ 69
12.1. A-Board ----------------------------------------------------- 69
12.2. A-Board ----------------------------------------------------- 71
12.3. P-Board ----------------------------------------------------- 72
12.4. P-Board ----------------------------------------------------- 73
12.5. K-Board ----------------------------------------------------- 74
12.6. K-Board ---------------------------------------------------- 74
12.7. V-Board----------------------------------------------------- 74
12.8. V-Board----------------------------------------------------- 74
12.9. TC-Board -------------------------------------------------- 75
12.10. TC-Board -------------------------------------------------- 75
13 Exploded View and Replacement Parts List----------- 76
13.1. Exploded View and Mechanical Replacement
Parts List --------------------------------------------------- 76
13.2. Electrical Replacement Parts List ------------------- 76
13.2.1. Replacement Parts List Notes ------------------- 76
13.2.2. Electrical Replacement Parts List--------------- 77

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1 Safety Precautions
1.1. General Guidelines
1. When servicing, observe the original lead dress. If a short circuit is found, replace all parts which have been overheated or
damaged by the short circuit.
2. After servicing, see to it that all the protective devices such as insulation barriers, insulation papers shields are properly
installed.
3. After servicing, make the following leakage current checks to prevent the customer from being exposed to shock hazards.
4. When conducting repairs and servicing, do not attempt to modify the equipment, its parts or its materials.
5. When wiring units (with cables, flexible cables or lead wires) are supplied as repair parts and only one wire or some of the
wires have been broken or disconnected, do not attempt to repair or re-wire the units. Replace the entire wiring unit instead.
6. When conducting repairs and servicing, do not twist the Faston connectors but plug them straight in or unplug them straight
out.
1.1.1. Leakage Current Cold Check
1. Unplug the AC cord and connect a jumper between the
two prongs on the plug.
2. Measure the resistance value, with an ohmmeter,
between the jumpered AC plug and each exposed
metallic cabinet part on the equipment such as
screwheads, connectors, control shafts, etc. When the
exposed metallic part has a return path to the chassis, the
reading should be 100 Mohm and over.
When the exposed metal does not have a return path to
the chassis, the reading must be .
1.1.2. Leakage Current Hot Check (See
Figure 1.)
1. Plug the AC cord directly into the AC outlet. Do not use
an isolation transformer for this check.
2. Connect a 1.5kohm, 10 watts resistor, in parallel with a
0.15μF capacitors, between each exposed metallic part
on the set and a good earth ground such as a water pipe,
as shown in Figure 1.
3. Use an AC voltmeter, with 1000 ohms/volt or more
sensitivity, to measure the potential across the resistor.
4. Check each exposed metallic part, and measure the
voltage at each point.
5. Reverse the AC plug in the AC outlet and repeat each of
the above measurements.
6. The potential at any point should not exceed 0.75 volts
RMS. A leakage current tester (Simpson Model 229 or
equivalent) may be used to make the hot checks, leakage
current must not exceed 1/2 milliamp. In case a
measurement is outside of the limits specified, there is a
possibility of a shock hazard, and the equipment should
be repaired and rechecked before it is returned to the
customer.
Figure 1

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2Warning
2.1. Prevention of Electrostatic Discharge (ESD) to Electrostatically
Sensitive (ES) Devices
Some semiconductor (solid state) devices can be damaged easily by static electricity. Such components commonly are called
Electrostatically Sensitive (ES) Devices. Examples of typical ES devices are integrated circuits and some field-effect transistors and
semiconductor [chip] components. The following techniques should be used to help reduce the incidence of component damage
caused by electrostatic discharge (ESD).
1. Immediately before handling any semiconductor component or semiconductor-equipped assembly, drain off any ESD on your
body by touching a known earth ground. Alternatively, obtain and wear a commercially available discharging ESD wrist strap,
which should be removed for potential shock reasons prior to applying power to the unit under test.
2. After removing an electrical assembly equipped with ES devices, place the assembly on a conductive surface such as
aluminum foil, to prevent electrostatic charge buildup or exposure of the assembly.
3. Use only a grounded-tip soldering iron to solder or unsolder ES devices.
4. Use only an anti-static solder removal device. Some solder removal devices not classified as [anti-static (ESD protected)] can
generate electrical charge sufficient to damage ES devices.
5. Do not use freon-propelled chemicals. These can generate electrical charges sufficient to damage ES devices.
6. Do not remove a replacement ES device from its protective package until immediately before you are ready to install it. (Most
replacement ES devices are packaged with leads electrically shorted together by conductive foam, aluminum foil or
comparable conductive material).
7. Immediately before removing the protective material from the leads of a replacement ES device, touch the protective material
to the chassis or circuit assembly into which the device will be installed.
Caution
Be sure no power is applied to the chassis or circuit, and observe all other safety precautions.
8. Minimize bodily motions when handling unpackaged replacement ES devices. (Otherwise ham less motion such as the
brushing together of your clothes fabric or the lifting of your foot from a carpeted floor can generate static electricity (ESD)
sufficient to damage an ES device).

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2.2. About lead free solder (PbF)
Note: Lead is listed as (Pb) in the periodic table of elements.
In the information below, Pb will refer to Lead solder, and PbF will refer to Lead Free Solder.
The Lead Free Solder used in our manufacturing process and discussed below is (Sn+Ag+Cu).
That is Tin (Sn), Silver (Ag) and Copper (Cu) although other types are available.
This model uses Pb Free solder in it’s manufacture due to environmental conservation issues. For service and repair work, we’d
suggest the use of Pb free solder as well, although Pb solder may be used.
PCBs manufactured using lead free solder will have the PbF within a leaf Symbol PbF stamped on the back of PCB.
Caution
• Pb free solder has a higher melting point than standard solder. Typically the melting point is 50 ~ 70 °F (30~40 °C) higher. Please
use a high temperature soldering iron and set it to 700 ± 20 °F (370 ± 10 °C).
• Pb free solder will tend to splash when heated too high (about 1100 °F or 600 °C).
If you must use Pb solder, please completely remove all of the Pb free solder on the pins or solder area before applying Pb
solder. If this is not practical, be sure to heat the Pb free solder until it melts, before applying Pb solder.
• After applying PbF solder to double layered boards, please check the component side for excess solder which may flow onto the
opposite side. (see figure below)
Suggested Pb free solder
There are several kinds of Pb free solder available for purchase. This product uses Sn+Ag+Cu (tin, silver, copper) solder.
However, Sn+Cu (tin, copper), Sn+Zn+Bi (tin, zinc, bismuth) solder can also be used.

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3 Service Navigation
3.1. Service Hint
Board Name Function
A BOARD AVSW, TUN, OFDM, ADV, P-AVC, GENX, EEP, TEMP
V BOARD Remote, LED, Luminunce Sensor
K BOARD CONTROL BUTTON, POWER BUTTON
P BOARD Power Supply
T CON BOARD T-CON for LG 100Hz panel

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4 Specifications
Power Source AC 110 V, 50 / 60 Hz
Power Consumption
Average use 200 W
Standby condition 0.4 W
Display panel
Aspect Ratio 16:9
Visible screen size 106 cm (diagonal)
930 mm (W) ×523 mm (H)
Number of pixels 2,073,600 (1,920 (W) ×1,080 (H)) [5,760 ×1,080 dots]
Sound
Speaker 160 mm ×42 mm ×2 pcs, 8 Ω
Audio Output 20 W (10 W + 10 W), 10% THD
Headphones M3 (3.5 mm) stereo mini Jack ×1
PC signals VGA, SVGA, WVGA, XGA
SXGA, WXGA ...... (compressed)
Horizontal scanning frequency 31 - 69 kHz
Vertical scanning frequency 59 - 86 Hz
Receiving Systems / Band name 17 SYSTEMS FUNCTIONS
1PAL B, G, H
Reception of broadcast transmission and
playback from video cassette tape recorders.
2PAL I
3PAL D, K
4SECAM B, G
5SECAM D, K
6SECAM K1
7NTSC M (NTSC 3.58 / 4.5MHZ)
8NTSC 4.43 / 5.5 MHz
Playback from special VCR’s or DVD.
9NTSC 4.43 / 6.0 MHz
10 NTSC 4.43 / 6.5 MHz
11 NTSC 3.58 / 5.5 MHz
12 NTSC 3.58 / 6.0 MHz
13 NTSC 3.58 / 6.5 MHz
14 SECAM I
15 PAL 60 Hz / 5.5 MHz Playback from Special Disc Players and
Special VCR’s or DVD.
16 PAL 60 Hz / 6.0 MHz
17 PAL 60 Hz / 6.5 MHz
Receiving Channels (Analogue TV)
VHF BAND 2 - 12 (PAL / SECAM B, K1)
0 - 12 (PAL B AUST.)
1 - 9 (PAL B N.Z.)
1 - 12 (PAL / SECAM D)
1 - 12 (NTSC M JAPAN)
2 - 13 (NTSC M USA)
UHF BAND 21 - 69 (PAL G, H, I / SECAM G, K, K1)
28 - 69 (PAL B AUST.)
13 - 57 (PAL D, K)
13 - 62 (NTSC M JAPAN)
14 - 69 (NTSC M USA)
CATV S1 - S20 (OSCAR)
1 - 125 (USA CATV)
C13 - C49 (JAPAN)
S21 - S41 (HYPER)
Z1 - Z37 (CHINA)
5A, 9A (AUST.)
Aerial - Rear VHF / UHF
Operating Conditions Temperature : 0°C - 40°C
Humidity : 20 % - 80 % RH (non-condensing)
Connection Terminals
AV1 Input AUDIO L-R RCA PIN Type ×2 0.5 V [rms]
VIDEO RCA PIN Type ×1 1.0 V [p-p] (75 Ω)
COMPONENT Y 1.0 V [p-p] (including synchronization)
PB/CB, PR/CR± 0.35 V [p-p]
AV2 Input AUDIO L-R RCA PIN Type ×2 0.5 V [rms]
VIDEO RCA PIN Type ×1 1.0 V [p-p] (75 Ω)
AV3 Input AUDIO L-R RCA PIN Type ×2 0.5 V [rms]
VIDEO RCA PIN Type ×1 1.0 V [p-p] (75 Ω)

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Note
• Design and Specifications are subject to change without notice. Mass and Dimensions shown are approximate.
Monitor Output AUDIO L-R RCA PIN Type ×2 0.5 V [rms] (high impedance)
VIDEO RCA PIN Type ×1 1.0 V [p-p] (75 Ω)
Others HDMI 1 - 3 Input TYPE A Connectors • This TV supports ‘HDAVI Control 5’ function.
PC Input HIGH-DENSITY D-SUB 15 PIN R / G / B: 0.7 V [p-p] (75 Ω)
HD / VD: TTL LEVEL 2.0-5.0 V [p-p] (high impedance)
DIGITAL AUDIO OUT PCM / Dolby Digital, Fiber optic
Card Slot SD Card slot ×1
USB 1/2 USB 2.0 Type A connector DC 5V, Max 500mA
ETHERNET 10BASE-T / 100BASE-TX
Dimension (W x H x D) 1,021 mm ×680 mm ×310 mm (With Pedestal)
1,021 mm ×637 mm ×105 mm (TV only)
Mass 21.0 kg Net (With Pedestal)
18.0 kg Net (TV only)

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5 Service Mode
5.1. How to enter into Service Mode
While pressing [VOLUME ( - )] button of the main unit, press [INFO] button of the remote control three times within 2 seconds.
5.1.1. Contents of adjustment mode
• Value is shown as a hexadecimal number.
• Preset value differs depending on models.
• After entering the adjustment mode, take note of the value in each item before starting adjustment.
5.1.2. How to exit
Switch off the power with the [POWER] button on the main unit or the [POWER] button on the remote control.
Main item Sub item Sample Data Remark
ADJUST CONTRAST 000
COLOR 4C
TINT 00
SUB-BRT 808
BACKLGT 22E
B-Y-G 34
R-Y-A 00
WB-ADJ R-GAIN F7
G-GAIN FB
B-GAIN DB
R-CENT 82
G-CENT 80
B-CENT 86
OPTION Boot ROM Factory Preset.
STBY-SET 00
EMERGENCY ON
CLK MODE 00
CLOCK 0E4
RM-SET 00 Fixed.
SRV-TOOL 00 See next.

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5.2. SRV-TOOL
5.2.1. How to access
1. Select [SRV-TOOL] in Service Mode.
2. Press [OK] button on the remote control.
5.2.2. Display of SOS History
SOS History (Number of LED blinking ) indication.
From left side; Last SOS, before Last, three occurrence before, 2nd occurrence after shipment, 1st occurrence after shipment.
This indication except 2nd and 1st occurrence after shipment will be cleared by [Self-check indication and forced to factory
shipment setting].
5.2.3. POWER ON TIME/COUNT
Note : To display TIME/COUNT menu, highlight position, then press MUTE for 3sec.
Time : Cumulative power on time, indicated hour : minute by decimal
Count : Number of ON times by decimal
Note : This indication will not be cleared by either of the self-checks or any other command.
5.2.4. Exit
1. Disconnect the AC cord from wall outlet.

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5.3. Service Mode Adjustment
1. Press the ‘RECALL’ button on the remote control and press ‘-’ vol button on the LCD panel.
2. Press button number 1 on the remote control to select for Adjustment.
3. Self Check to Exit.
5.3.1. Self Check Mode
1. Press the ‘MENU’ button (on the remote control) and the ‘DOWN’ button on the LCD panel.
2. Press ON/OFF button on the panel to Exit.
5.3.2. Hotel Mode Adjustment
1. Press the ‘VOLUME DOWN’ button on the TV panel and simultaneously press the AV button on the remote control 3 times to
enter Hotel Mode.
2. Set Hotel mode ‘on’, then press ‘EXIT’ to come out.
5.3.3. Hotel Mode
Item Function
Hotel Mode Select hotel mode ON/OFF
Initial INPUT Select input signal modes.
Set the input, when each time power is switched
on.
Selection :
OFF/Analogue TV/Digital TV/AV1/AV2/AV3/PC/
HDMI1/HDMI2/HDMI3
• Off: give priority to a last memory.
• Selectable input is depend on the model.
Initial POS Select programme number.
Selection :
Off/0 to 100
• Off: give priority to a last memory.
Initial VOL level Adjust the volume when each time power is
switched on.
Selection/Range :
Off/0 to 100
• Off: give priority to a last memory.
Maximum VOL
level
Adjust maximum volume.
Range :
0 to 100
Button lock Select local key conditions.
Selection :
Off/SETUP/MENU/All
• Off: altogether valid.
• SETUP: only F-key is invalid.
(Tuning guide (menu) can not be selected.)
• MENU: only F-key is invalid.
(only Volume/Mute can be selected.)
• ALL: altogether invalid.
Remote lock Select remote control key conditions.
Selection :
Off/SETUP/MENU
• Off: altogether valid.
• SETUP: only Setup menu is invalid.
• MENU: Picture/Sound/Setup menu are invalid.

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6 Troubleshooting Guide
Use the self-check function to test the unit.
1. Checking the IIC bus lines
2. Power LED Blinking timing
6.1. Check of the IIC bus lines
6.1.1. How to access
Self-check indication only:
Produce TV reception screen, and while pressing [VOLUME ( - )] button on the main unit, press [OK] button on the remote control
for more than 3 seconds.
Self-check indication and forced to factory shipment setting:
Produce TV reception screen, and while pressing [VOLUME ( - )] button on the main unit, press [MENU] button on the remote
control for more than 3 seconds.
6.1.2. Exit
Disconnect the AC cord from wall outlet.
6.1.3. Screen display
6.1.4. Check Point
Confirm the following parts if NG was displayed.

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6.2. Power LED Blinking timing chart
1. Subject
Information of LED Flashing timing chart.
2. Contents
When an abnormality occurs, the protection circuit will operate and reset the unit to stand by mode. During this time, the
defective block can be identified by the number of blinking times of the Power LED on the front panel of the unit as follow:
6.3. No Power
First check point
There are following 2 states of No Power indication by power LED.
1. No lit
2. Red is lit then turns red blinking a few seconds later. (See 6.2.)
Blinking times Contents
1 Inverter_SOS
2FAN_SOS
3SOS
4 SUB 12V_SENSE_SOS
7 Sub_ 3.3V_SENSE_SOS
9 SOUND_SOS
12 BE)Sld)_SOS
13 Emergency SOS

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7 Disassembly and Assembly Instructions
7.1. AC Cord Dressing
1. Clamp plug with clamper.
2. Insert beads 3pcs. And slide down to lower hole.

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7.2. AC Cord Installation
1. Put on the AC CORD BRACKET on the CABINET.
2. Fix the AC CORD BRACKET with SCREW.
3. Insert AC CORD connector into P-PCB connector.
4. Clamp the AC CORD.
5. Insert AC CORD bushing into the AC CORD BRACKET.
6. AC CORD is pushed into the bottom of the bracket.

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7.3. Control Panel Fitting
1. Put control panel Assy on the cabinet.
2. Fix the control panel with screws.

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7.4. Side AV Bracket Preparation
1. Stick the side av indi. Sheet on the side av bracket.
2. Insert the SIDE AV BRACKET from the side position of the A-PCB.
3. Fix the SCREW with A-PB-MTG METAL.

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7.5. Speaker Preparation and Installation
1. SP bracket put on cabinet.
2. Fix them with screws.
3. Insert the SP rubber bush into the SP unit.
4. Insert the SP unit to SP bracket.

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7.6. LCD Panel Fixing & Handling Method
1. Place down the cabinet as shown below.
2. Fix LCD panel into the cabinet by taking below precautions.
Other general precautions
1. Do not press panel surface to avoid blue spot on the panel display.
2. Do not use hard cloth or rub the surface too hard. This may cause scratches on the surface.
3. Take care not to subject the TV’s surface to water or detergent. Any liquid (including pets urine) if enters the product could
lead to TV failure.
4. Take care not to subject the surface to insect repellent, solvent, thiner or other voiltile substances. This may degrade surface
quality or cause peeling of the paint.
5. The surface of the display panel is specially treated and may be easily damaged. Take care not to tap or scratch with your
fingernail or other hard objects.

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7.7. LED Panel Installation
1. Fix LED PANEL on CABINET.
2. Wire connecting. (V10)
3. Put V-PCB on CABINET.
4. Fix them with SCREW.
5. Insert the CALMPER.