Panasonic TC-L42E5X Schematic

© Panasonic Corporation 2012. Unauthorized
copying and distribution is a violation of law.

ORDER NO. MTV1204025CE

LCD HDTV

Model No. TC-L42E5X

Chassis: LA35

Destination: USA

TABLE OF CONTENTS

PAG E PAG E

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 ------------------------------------------------------ 8

5.1. How to enter into Service Mode ----------------------- 8

5.1.1. Contents of adjustment mode --------------------- 8

5.1.2. How to exit---------------------------------------------- 8

5.2. SRV-TOOL -------------------------------------------------- 9

5.2.1. How to access ----------------------------------------- 9

5.2.2. Display of SOS History ------------------------------ 9

5.2.3. POWER ON TIME/COUNT ------------------------ 9

5.2.4. Exit -------------------------------------------------------- 9

5.2.5. Self Check Mode ------------------------------------ 10

5.2.6. Hotel Mode Adjustment ---------------------------- 10

5.2.7. Hotel Mode-------------------------------------------- 10

6 Troubleshooting Guide --------------------------------------- 11

6.1. Check of the IIC bus lines------------------------------ 11

6.1.1. How to access --------------------------------------- 11

6.1.2. Exit ------------------------------------------------------ 11

6.1.3. Screen display --------------------------------------- 11

6.2. Power LED Blinking timing chart --------------------- 12

6.3. No Power--------------------------------------------------- 12

7 Disassembly and Assembly Instructions--------------- 13

7.1. Control Panel Preparation ----------------------------- 13

7.2. Control Panel Assembly-------------------------------- 14

7.3. Speaker Assembly--------------------------------------- 15

7.4. Panel Assembly ------------------------------------------ 16

7.5. LCD Panel Fixing & Handling Method -------------- 17

7.6. Placing Black Tape -------------------------------------- 18

7.7. LED Panel Assembly------------------------------------ 19

7.8. Screwing up Brackets----------------------------------- 20

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7.9. Plate Metal Part Assembly-----------------------------21

7.10. LVDS Cable Assembly---------------------------------- 22

7.11. Fitting the Barrier ----------------------------------------- 23

7.12. Plate A Assembly ---------------------------------------- 24

7.13. Plate P Assembly ---------------------------------------- 25

7.14. Assembling the Metal AV Bracket Side------------- 26

7.15. Assembling the Metal AV Bracket BTM ------------27

7.16. Bottom Cover Assembly--------------------------------28

7.17. Screwing up the Back Cover -------------------------- 29

8 Measurements and Adjustments -------------------------- 30

8.1. Voltage chart of A-board-------------------------------- 30

8.2. Voltage chart of P-board-------------------------------- 30

9 Block Diagram --------------------------------------------------- 31

9.1. Main Block Diagram ------------------------------------- 31

9.2. Detailed Block Diagram (1/2)-------------------------- 32

9.3. Detailed Block Diagram (2/2)-------------------------- 33

10 Wiring Connection Diagram --------------------------------- 34

10.1. Cable Alignment ------------------------------------------ 34

11 Schematic Diagram--------------------------------------------- 36

11.1. Schematic Diagram Notes ----------------------------- 36

11.2. A-Board (1/17) Schematic Diagram ----------------- 37

11.3. A-Board (2/17) Schematic Diagram ----------------- 38

11.4. A-Board (3/17) Schematic Diagram ----------------- 39

11.5. A-Board (4/17) Schematic Diagram ----------------- 40

11.6. A-Board (5/17) Schematic Diagram ----------------- 41

11.7. A-Board (6/17) Schematic Diagram ----------------- 42

11.8. A-Board (7/17) Schematic Diagram ----------------- 43

11.9. A-Board (8/17) Schematic Diagram ----------------- 44

11.10. A-Board (9/17) Schematic Diagram ----------------- 45

11.11. A-Board (10/17) Schematic Diagram --------------- 46

11.12. A-Board (11/17) Schematic Diagram---------------- 47

11.13. A-Board (12/17) Schematic Diagram --------------- 48

11.14. A-Board (13/17) Schematic Diagram --------------- 49

11.15. A-Board (14/17) Schematic Diagram --------------- 50

11.16. A-Board (15/17) Schematic Diagram --------------- 51

11.17. A-Board (16/17) Schematic Diagram --------------- 52

11.18. A-Board (17/17) Schematic Diagram --------------- 53

11.19. GK-Board Schematic Diagram ----------------------- 54

11.20. K-Board Schematic Diagram -------------------------- 55

11.21. P-Board Schematic Diagram -------------------------- 56

12 Printed Circuit Board ------------------------------------------ 57

12.1. A-BOARD -------------------------------------------------- 57

12.2. K-BOARD -------------------------------------------------- 59

12.3. P-BOARD -------------------------------------------------- 60

13 Exploded View and Replacement Parts List -----------62

13.1. Exploded View and Mechanical Replacement
Parts List --------------------------------------------------- 62

13.2. Electrical Replacement Parts List -------------------- 62

13.2.1. Replacement Parts List Notes ------------------- 62

13.2.2. Electrical Replacement Parts List ---------------63

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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)

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3 Service Navigation

3.1. Service Hint

Board Name Main Device Remarks

A BOARD TUN, OFDM, ADV, LD4, STBY EEP Repairable

P BOARD Power Supply Repairable

GK BOARD Function SW for LGD panel Repairable

K BOARD LED/RM/CATS Repairable

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4 Specifications

Note

• Design and Specifications are subject to change without notice. Mass and Dimensions shown are approximate.

Power Source AC 110-127 V, 60 Hz
Power Consumption

Rated Power Consumption 85 W
Standby condition 0.1 W

Display panel

Aspect Ratio 16:9
Visible screen size 42” class (42 inches measured diagonally)
Number of pixels 2,073,600 (1,920 (W) × 1,080 (H)) [5,760 × 1,080 dots]

Sound

Speaker 1-way 2 bottom SP System
Audio Output 20 W [10 W + 10 W], (10% THD)

PC signals VGA, WVGA, SVGA, XGA, WXGA, SXGA

Horizontal scanning frequency 31 - 64 kHz
Vertical scanning frequency 59 - 61 Hz

Channel Capability-ATSC/NTSC (Digital/Analog) VHF/ UHF: 2 - 69, CATV: 1 - 135
Operating Conditions Temperature : 32°F - 95°F (0°C - 35°C)

Humidity : 20 % - 80 % RH (non-condensing)

Connection Terminals

VIDEO IN VIDEO: RCA PIN Type × 1 1.0V [p-p] (75 Ω)

AUDIO L - R RCA PIN Type × 2 0.5V [rms]

COMPONENT IN Y: 1.0 V [p-p] (including synchronization)

P

B

, PR: ± 0.35 V [p-p]

AUDIO L - R: RCA PIN Type × 2 0.5 V [rms]

HDMI 1-4 TYPE A Connector × 4

• This TV supports ‘HDAVI Control 5’ function.

USB USB 2.0 Type A connector × 2 (DC5V MAX500mA)
LAN (for IPTV) RJ45 (10BASE-T/100BASE-TX)
PC D-SUB 15 PIN: R, G, B / 0.7 V [p-p] (75 Ω)

HD, VD / 1.0-5.0 V [p-p] (high impedance)

Card slot SD CARD slot × 1
DIGITAL AUDIO OUT PCM / Dolby Digital, Fiber Optic

FEATURES 3D Y/C FILTER CLOSED CAPTION

V-Chip EASY IPTV Vesa compatible
VIERA IMAGE VIEWER Media player HDAVI Control 5

Dimensions (W x H x D)

Including TV Stand 39.3” × 25.6” × 9.8”

(997 mm × 650 mm × 247 mm)

TV Set only 39.3” × 23.8” × 2.1”

(997 mm × 604 mm × 52 mm)

Mass

Including TV stand 37.5 lb. (17 kg) NET
TV Set only 30.9 lb. (14 kg) NET

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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

ADJUST CONTRAST 000

COLOR 59

TINT FE

SUB-BRT 800

BACKLGT 20D

B-Y-G 40

R-Y-A 0

VCOM 189

WB-ADJ R-GAIN 75

G-GAIN 80

B-GAIN 65

R-CENT 80

G-CENT 80

B-CENT 9B

OPTION Boot ROM

STBY-SET 00

EMERGENCY ON

CLK MODE 00

CLOCK FC7

EDID-CLK HIGH

SRV-TOOL 00

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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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5.2.5. Self Check Mode

1. Press the ‘MENU’ button (on the remote control) and the ‘VOL DOWN’ button on the LCD panel.

2. Press ON/OFF button on the panel to Exit.

5.2.6. Hotel Mode Adjustment

1. Press the ‘VOLUME DOWN’ button on the TV panel and simultaneously press the INPUT button on the remote control 3
times to enter Hotel Mode.

2. Set Hotel mode ‘on/off’, then press ‘EXIT’ to come out.

5.2.7. Hotel Mode

1. Purpose
Restrict a function for hotels.

2. Access command to the Hotel mode setup menu.
In order to display the Hotel mode setup menu, please
enter the following command (within 2 second).
[TV] : Vol [Down] + [REMOTE] : INPUT (3 times).

Then, the Hotel mode setup menu is displayed.

3. To exit the Hotel mode setup menu
Disconnect AC power cord from wall outlet.

4. Explain the Hotel mode setup menu

Item Function

Mode Select hotel mode off/on

Input Select input signal modes.

Set the input, when each time power is switched
on.
Selection :

-/RF/HDMI1/HDMI2/HDMI3/Component/
Video/PC

• Off: give priority to a last memory.

Channel Select channel when input signal is RF.

Set the channel, each time power is switched
on.
Selection :
Any channel number or [-].
[-] means the channel when turns off.

Volume Adjust the volume when each time power is

switched on.
Range :
0 to 100

Vol. Max Adjust maximum volume.

Range :
0 to 100

OSD Ctrl Restrict the OSD.

Selection :
OFF/PATTERN1

• OFF: No restriction

• PATTERN1: restriction

FP Ctrl Select front key conditions.

Selection :
OFF/PATTERN1/ALL

• OFF: altogether valid.

• PATTERN1: only input key is valid.

• ALL: altogether invalid.

Pow Ctrl Select POWER-ON/OFF condition when AC

power cord is disconnected and then connected.
OFF: The same condition when AC power
cord is disconnected.
ON: Forced power ON condition.

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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

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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.)

Priority Name Factor R_LED Blink

1 BL_SOS SOS from PANEL inverter 1

2 POWER_SOS SOS from POWER Curcuit 3

3 SOUND_SOS SOS from audio AMP 9

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7 Disassembly and Assembly Instructions

7.1. Control Panel Preparation

1. Fit the GK plate on the key button guide pins indicated by the pointed arrows.

2. Screw in the positions indicated using the corresponding torque.

3. Connect the cable to the GK plate connector.

No. Part Num. Quant. Description

1 TBX5ZA00601 1 KEY_BUTTON

2 TXNGK1SLUU 1 GK PANEL COMPLETE FROM KATOLEC

3 TXJ/P4SLUU 1 CABLE ASSY (P4-LD/GK4)

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7.2. Control Panel Assembly

1. Place the control panel preparation on the cabinet guide pins, as indicated by the pointed arrows.

2. Screw in the positions indicated using the corresponding torque.

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7.3. Speaker Assembly

1. Fit the speaker brackets, inserting the bracket pins into the holes in the panel.

2. Screw in the positions indicated using the corresponding torque.

3. Insert the speaker in the speaker brackets.

No. Part Num. Quant. Description

1 TKX5ZA02501 4 SPEAKER BRACKET

2 L0EYAA000007 1 SPEAKER UNIT R

3 L0EYAA000006 1 SPEAKER UNIT L

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7.4. Panel Assembly

1. Fit the panel to the cabinet, handling it extremely carefully. Fig A

2. Once the panel has been fitted to the cabinet, pull the panel towards the cabinet until it meets the stops.

3. Take extreme care not to knock the cabinet with the corners of the panel.

4. Stick the tape on top of the plate K cable, as indicated in. Fig B

No. Part Num. Quant. Description

1 L5EDDYY00359 1 LCD PANEL

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7.5. 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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7.6. Placing Black Tape

1. Place the black tape in the position indicated. See detail 1

2. Place the aluminium tape in the position indicated. See detail 2

3. Place the gasket in the position indicated, see dotted circles.

No. Part Num. Quant. Description

1 TEWF097 4 ALUMI TAPE 15*40(PANEL LR)

2 TEWB763 2 GASKET (T12*W10*L20)

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7.7. LED Panel Assembly

1. Prepare the LED panel as indicated, Fig A.

2. Assemble the prepared LED as shown in Fig B.

No. Part Num. Quant. Description

1 TXFKK5Z0004 1 ASSY, LED PANEL

2 TXFKK5Z0006 1 ASSY, LED BRACKET

3 TXN/K1SKUUS 1 ASSY, K PANEL COMPLETE PAVCAP

4 TXJA10TCUU 1 WIRE (A10-K10)

5 TXFKY5Z0311 1 ASSY, CABINET

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7.8. Screwing up Brackets

1. Place the metal Vesas in the positions indicated. Fig A

2. Place the bottom metal part in the position indicated. Fig B

3. Screw in the positions indicated using the corresponding torque.

4. Insert the clampers in the position indicated. Fig B

Note: Use metal part without (-1) for PP2, the next production will be received with (-1)

No. Part Num. Quant. Description

1 TKZ5ZX5011 1 BOTTOM_METAL

2 TKZ5ZX5006-1 2 VESA METAL

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7.9. Plate Metal Part Assembly

1. Place the gasket at the bottom of the metal parts, see figure 1.

2.

Place the metal parts in the positions indicated, insert the metal part guide pins into the holes on the panel, as shown in detail A.

3. Place the gasket on one side of metal part L, then cover it with 2 strips of 35 mm tape. See figure 2.

4. Screw in the positions indicated using the corresponding torque.

No. Part Num. Quant. Description

1 TUA5ZA03201 1 METAL_CH_FRAME_L

2 TUA5ZA04301 1 METAL_CH_FRAME_R

3 TEWB809 1 GASKET(T15 × W15 × L25)

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7.10. LVDS Cable Assembly

1. Connect the LVDS cables as indicated.

2. Place the tape in the position indicated, starting with letter A.

No. Part Num. Quant. Description

1 TSCFF0030012 1 LVDS CABLE