Panasonic TC-26LX70L, TC-32LX70L Service manual

TC-26LX70L

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TC-32LX70L

LH58A Chassis

ORDER NO.MTNC070521CE

B05 Canada: B07

LCD Television

Specifications

Power Source
Power Consumption

Average use 105 W (TC-26LX70L)

Maximum Current 1.3 A (TC-26LX70L)

Standby condition 0.6 W
Aspect Ratio 16 : 9
Visible screen size

(W × H × Diagonal)

(No. of pixels) 1,049,088 (1,366 (W) × 768(H)) [4,098 × 768 dots]

Sound

Speaker 60 mm × 120 mm Gama completa × 2 pcs
Audio Output 20 W [ 10 W + 10 W ] ( 10 % THD )

Headphones M3 (3.5mm) Jack × 1
Channel Capability VHF/UHF: 2 - 69, CATV: 1 - 125
Operating Conditions Temperature: 32 °F - 95 °F (0 °C - 35 °C)
Connection Terminals

INPUT 1-2 VIDEO: RCA PIN Type × 1 1.0 V [p-p] (75 ohm)

INPUT 3 VIDEO: RCA PIN Type × 1 1.0 V [p-p] (75 ohm)

COMPONENT

VIDEO INPUT

C 110-220 V, 50/60 Hz

118 W (TC-32LX70L)

1.5 A (TC-32LX70L)

26.0 " DIAGONAL (66.1 cm DIAGONAL) (TC-26LX70L)

31.5 " DIAGONAL (80.0 cm DIAGONAL) (TC-32LX70L)
576 mm × 324 mm × 661 mm (TC-26LX70L)
698 mm × 392 mm × 800 mm (TC-32LX70L)

S-VIDEO: Mini DIN 4-pin Y: 1.0 V [p-p] (75 ohm) C: 0.286 V [p-p] (75 ohm)

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

UDIO L-R: RCA PIN Type × 2 0.5 V [rms]
Y: 1.0 V [p-p] (including synchronization)
PB,PR: ± 0.35 V [p-p]

© 2007 Matsushita Electric Industrial Co., Ltd. All
rights reserved. Unauthorized copying and
distribution is a violation of law.

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TC-26LX70L / TC-32LX70L

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

HDMI TYPE A Connector × 1
AUDIO IN
OUTPUT VIDEO: RCA PIN Type × 1 1.0 V [p-p] (75 ohm)

FEATURES 3D Y/C Digital Comb Filter, CLOSED CAPTION, V-Chip

Dimensions (W × H × D)

Including TV stand 657 mm × 525 mm × 239 mm (TC-26LX70L)

TV Set only 657 mm × 473 mm × 117 mm (TC-26LX70L)

Mass 14.0 kg NET (TC-26LX70L)

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

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

HDMI
Vesa compatible

791 mm × 615 mm × 239 mm (TC-32LX70L)

791 mm × 563 mm × 117 mm (TC-32LX70L)

17.0 kg NET (TC-32LX70L)

Note:

Design and Specifications are subject change without notice. Weight and Dimensions shown are approximate.

CONTENTS

Page Page

1 Applicable signals 4
2 Safety Precautions

2.1. General Guidelines

3 Prevention of Electrostatic Discharge (ESD) to

Electrostatically Sensitive (ES) Devices
4 About lead free solder (PbF)
5 Chassis Board Layout
6 Disassembly for Service

6.1. Pedestal assy

6.2. Rear cover

6.3. AC cord

6.4. Tuner cover

6.5. Power button bracket

6.6. Control panel assy

6.7. G-Board

6.8. Side AV bracket and Inverter shield

6.9. Rear fixing MTG

6.10. AP-Board

6.11. P-Board

6.12. A-Board

6.13. Chassis assy

6.14. LCD MTG and LCD panel

6.15. Speaker

6.16. V-Board

7 Caution statement

7.1. Caution statement.

8 Location of Lead Wiring

8.1. Wire dressing (32 inch)

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8.2. Wire dressing (26 inch)

9 EMI Processing

9.1. EMI (32 inch)

9.2. EMI (26 inch)

10 Self-c heck Function

10.1. Check of the IIC bus lines

10.2. Power LED Blinking timing chart

10.3. No Power

11 Service Mode

11.1. How to enter into Service Mode

12 Adjustment

12.1. Voltage chart of AP-board

12.2. White balance adjustment

12.3. MTS input level adjustment

12.4. MTS stereo separation adjustment

13 Hotel mode
14 Conductor Views

14.1. AP-Board

14.2. A-Board

14.3. G and V-Board

15 Sche matic and Block Diagr am

15.1. Schematic Diagram Notes

15.2. Block Diagram (1 of 2)

15.3. Block Diagram (2 of 2)

15.4. Interconnection Schematic Diagram

15.5. AP-Board (1 of 2) Schematic Diagram

15.6. AP-Board (2 of 2) Schematic Diagram

15.7. A-Board (1 of 5) Schematic Diagram

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15.8. A-Board (2 of 5) Schematic Diagram 40

15.9. A-Board (3 of 5) Schematic Diagram

15.10. A-Board (4 of 5) Schematic Diagram

15.11. A-Board (5 of 5) Schematic Diagram

15.12. G and V-Board Schematic Diagram

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16 Explo ded View and Replacement Parts List

16.1. Exploded View

16.2. Replacement Parts List Notes

16.3. Mechanical Replacement Parts List

16.4. Electrical Replacement Parts List

TC-26LX70L / TC-32LX70L

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TC-26LX70L / TC-32LX70L

1 Applicable signals

* Mark: Applicable input signal for Component (Y, PB,PR) and HDMI

horizontal frequency (kHz) vertical frequency (kHz) COMPONENT HDMI
525 (480) / 60i 15.73 59.94 * *
525 (480) /60p 31.47 59.94 * *
750 (720) /60p 45.00 59.94 * *
1,125 (1,080) /60i 33.75 59.94 * *

Note:

· Signals other than those shown above may not be displayed properly.

· The above signals are reformatted for optimal viewing on your display.

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TC-26LX70L / TC-32LX70L

2 Safety Precautions

2.1. General Guidelines

1. When conducting repairs and servicing, do not attempt to modify the equipment, its parts or its materials.

2. When wiring units (with cables, flexible cables or lead wires)are supplied as repair parts and only one wireor 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.

3. When conducting repairs and servicing, do not twist the Faston connectors but plugthem straight in orunplug them straightout.

4. 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.

5. After servicing, see to it that all the protective devices such as insulation barriers, insulation papers shields are properly
installed.

6. After servicing, make the following leakage current checks to prevent the customer from being exposed to shock hazards.

2.1.1. 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 100Mohm
and over.

When the exposed metal does not have a return path to

the chassis, the reading must be

Figure 1

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2.1.2. 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 ACplugintheACoutlet and repeat eachof 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.

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TC-26LX70L / TC-32LX70L

3 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 ESdevices.(Otherwiseham less motion suchasthebrushing
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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TC-26LX70L / TC-32LX70L

4 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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TC-26LX70L / TC-32LX70L

5 Chassis Board Layout

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6 Disassembly for Service

6.1. Pedestal assy

1. Lay down the unit so that the rear cover faces upward.

2. Remove the 4 screws.

3. Remove the pedestal assy.

TC-26LX70L / TC-32LX70L

6.3. AC cord

6.2. Rear cover

1. Remove the 16 (32”) / 14 (26”) screws.

2. Remove the rear cover.

1. Remove the bushing of the AC cord from the tuner cover.

2. Disconnect the connector (CN1) of AC cord.

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TC-26LX70L / TC-32LX70L

6.4. Tuner cover

1. Remove the 2 screws.

2. Remove the tuner cover.

6.6. Control panel assy

1. Remove the power button bracket. (See section 6.5.)

2. Disconnect the connector (AP6).

3. Remove the control panel assy.

6.7. G-Board

1. Remove the 2 screws.

2. Disconnect the connector (G4).

3. Remove the G-Board.

6.5. Power button bracket

1. Remove the 2 screws.

2. Remove the power button bracket.

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TC-26LX70L / TC-32LX70L

3. Remove the 2 screws (C).

4. Remove the side AV bracket and the inverter shield.

6.8. Side AV bracket and Inverter
shield

1. Remove the screw (A).

2. Remove the screw (B).

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TC-26LX70L / TC-32LX70L

6.9. Rear fixing MTG

1. Remove the 4 screws.

2. Remove the rear fixing MTG.

6.11. P-Board

1. Remove the 2 screws.

2. Remove the Barrier.

3. Disconnect the connectors (P301/P302).

4. Remove the 5 screws.

5. Remove the P-Board.

6.10. AP-Board

1. Remove the 6 screws.

2. Disconnect the connectors (A3/A4/AP5/AP7/P301/P302).

3. Remove the AP-Board.

6.12. A-Board

1. Remove the 7 screws (D).

2. Remove the A-Board shield case.

3. Remove the 4 screws (E).

4. Disconnect the connectors (A1/A2/A3/A4/A5/A6/A7).

5. Remove the A-Board.

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6.13. Chassis assy

1. Remove the 3 screws.

2. Remove the chassis assy.

TC-26LX70L / TC-32LX70L

6.14. LCD MTG and LCD panel

1. Remove the 10 (32”) / 6 (26”) screws (F).

2. Remove the 4 (32”) / 4 (26”) screws (G)

3. Remove the LCD MTG.

4. Remove the LCD panel.

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TC-26LX70L / TC-32LX70L

6.15. Speaker

1. Remove the 2 screws.

2. Remove the speaker.

6.16. V-Board

1. Remove the 2 screws.

2. Disconnect the connector (V1).

3. Remove the V-Board.

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7 Caution statement

7.1. Caution statement.

Caution:

Please confirm that all flexible cables are assembled correctly.
Also make sure that they are locked in the connectors.
Verify by giving the flexible cables a very slight pull.

TC-26LX70L / TC-32LX70L

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TC-26LX70L / TC-32LX70L

8 Location of Lead Wiring

8.1. Wire dressing (32 inch)

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8.2. Wire dressing (26 inch)

TC-26LX70L / TC-32LX70L

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