Panasonic TH-42LF20W User manual

© Panasonic Corporation 2010
Unauthorized copying and distribution is a violation
of law.
Order Number ITD1009084CE
FULL HD LCD Display
Model No. TH-42LF20W
Model No. TH-47LF20W
TABLE OF CONTENTS
PAGE PAGE
1 Safety Precautions----------------------------------------------- 3
1.1. General Guidelines---------------------------------------- 3
1.2. Touch-Current Check ------------------------------------- 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. Applicable signals ----------------------------------------- 6
4 Specifications ----------------------------------------------------- 8
5 Operating Instructions------------------------------------------ 9
6 Service Mode ----------------------------------------------------- 11
6.1. Service Menu Function (1) ----------------------------- 11
6.2. Service Menu Function (2) -----------------------------12
6.3. Service Mode Function (1) -----------------------------13
6.4. Service Mode Function (2) -----------------------------14
7 Troubleshooting Guide ----------------------------------------15
8 Disassembly and Assembly Instructions ---------------16
8.1. Flowchart for disassembly------------------------------16
8.2. Preparations----------------------------------------------- 17
8.3. Pedestal (option) removal------------------------------ 17
8.4. Rear cover removal-------------------------------------- 17
8.5. Replacement method for main board and jack
board -------------------------------------------------------- 18
8.6. Replacement method for Power board ------------- 19
8.7. Replacement method for AC cord bracket -------- 19
8.8. Cabinet back removal (42 type) ---------------------- 20
8.9. Cabinet back removal (47 type) ---------------------- 20
8.10. When removing the cabinet back with the
board connected ----------------------------------------- 20
8.11. Replacement method for speakers ------------------ 20
8.12. Key SW board replacement --------------------------- 20
8.13. Connector board removal ------------------------------ 21
8.14. LCD panel replacement -------------------------------- 21
8.15. Replacement method for RC+LED board---------- 22
8.16. Cabinet front replacement ----------------------------- 22
8.17. Cabinet back replacement ----------------------------- 23
9 Block Diagram --------------------------------------------------- 27

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9.1. Block (1 of 2) Diagram ---------------------------------- 27
9.2. Block (2 of 2) Diagram ---------------------------------- 28
10 Wiring Connection Diagram --------------------------------- 29
10.1. Wiring Connection Diagram (1)----------------------- 29
10.2. Wiring Connection Diagram (2)----------------------- 31
10.3. Wiring Connection Diagram (3)----------------------- 32
10.4. Wiring Connection Diagram (4)----------------------- 33
11 Exploded View and Replacement Parts List ----------- 34
11.1. Exploded View and Mechanical Replacement
Parts List --------------------------------------------------- 34
11.2. Mechanical Replacement Parts List (42 inch) ---- 51
11.3. Mechanical Replacement Parts List (47 inch) ---- 52
11.4. Electrical Replacement Boards list (42 inch)------ 53
11.5. Electrical Replacement Boards list (47 inch)------ 53
11.6. Boards Layout--------------------------------------------- 53

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1 Safety Precautions
1.1. 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 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.
3. When conducting repairs and servicing, do not twist the Fasten connectors but plug them straight in or unplug them straight
out.
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.
1.2. Touch-Current Check
1. Plug the AC cord directly into the AC outlet. Do not use an isolation transformer for this check.
2. Connect a measuring network for touch currents 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 Leakage Current Tester (Simpson 228 or equivalent) to measure the potential across the measuring network.
4. Check each exposed metallic part, and measure the voltage at each point.
5. Reserve the AC plug in the AC outlet and repeat each of the above measure.
6. The potential at any point (TOUCH CURRENT) expressed as voltage U1and U2, does not exceed the following values:
For a. c.: U1= 35 V (peak) and U2= 0.35 V (peak);
For d. c.: U1= 1.0 V,
Note:
The limit value of U2= 0.35 V (peak) for a. c. and U1= 1.0 V for d. c. correspond to the values 0.7 mA (peak) a. c. and 2.0
mA d. c.
The limit value U1= 35 V (peak) for a. c. correspond to the value 70 mA (peak) a. c. for frequencies greater than 100 kHz.
7. In case a measurement is out 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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TH-42LF20W / TH-47LF20W
2 Warning
2.1. Prevention of Electrostatic Discharge (ESD) to Electrostatically Sensi-
tive (ES) Devices
Some semiconductor (solid state) devices can be damaged easily by static electricity. Such components commonly are called Elec-
trostatically 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 alumi-
num 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 compara-
ble 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 brush-
ing 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 sol-
der. 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. How-
ever, Sn+Cu (tin, copper), Sn+Zn+Bi (tin, zinc, bismuth) solder can also be used.

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3 Service Navigation
3.1. Applicable signals

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TH-42LF20W / TH-47LF20W
4 Specifications
Power Source 220 - 240 V AC, 50/60Hz
Power Consumption
Power on 240 W (42 inch) 290 W (47 inch)
Stand-by condition 0.2 W (42 inch) 0.2 W (47 inch)
Power off condition 0.2 W (42 inch) 0.2 W (47 inch)
LCD Display panel 42-inch IPS panel, 16:9 aspect ratio (42 inch) 47-inch IPS panel, 16:9 aspect ratio (47 inch)
Screen size 930 mm (W) ×523 mm (H) ×1,067 mm (diagonal) (42 inch)
1,040 mm (W) ×585 mm (H) ×1,193 mm (diagonal) (47 inch)
(No.of pixels) 2,073,600 (1,920 (W) ×1,080 (H)) (42 inch) 2,073,600 (1,920 (W) ×1,080 (H)) (47 inch)
[5,760 ×1,080 dots] [5,760 ×1,080 dots]
Operating condition
Temperature 0 °C - 40 °C
Humidity 20 % - 80 %
Applicable signals
Colour System NTSC, PAL, PAL60, SECAM, NTSC 4.43, PAL M, PAL N
Scanning format 525 (480) / 60i 60p, 625 (575) / 50i 50p, 750 (720) / 60p 50p, 1125 (1080) /
60i 60p 50i 50p 24p 25p 30p 24sF, 1250 (1080) / 50i
PC signals VGA, SVGA, XGA, SXGA
UXGA ..... (compressed)
Horizontal scanning frequency 30 - 110 kHz
Vertical scanning frequency 48 - 120 Hz
Connection terminals
AV IN VIDEO BNC 1.0 Vp-p (75-ohm)
S-VIDEO Mini DIN 4PIN Y: 1.0 Vp-p (75-ohm), C: 0.286 Vp-p (75-ohm)
AUDIO L-R RCA Pin jack ×2 0.5 Vrms
HDMI 1/2 TYPE A Connector
COMPONENT / RGB IN
G/Y BNC with sync 1.0 Vp-p (75-ohm)
B/PB/CBBNC 0.7 Vp-p (75-ohm)
R/PR/CRBNC 0.7 Vp-p (75-ohm)
AUDIO L-R RCA Pin jack ×2 0.5 Vrms
DVI-D IN DVI-D 24 Pin Compliance with DVI Revision 1.0
Content Protection Compatible with HDCP 1.1
AUDIO Stereo mini jack (M3) ×1 0.5 Vrms, Shared with PC IN
PC IN High-Density Mini D-sub 15 Pin G with sync 1.0 Vp-p (75-ohm)
G without sync 0.7 Vp-p (75-ohm)
B:0.7 Vp-p (75-ohm)
R:0.7 Vp-p (75-ohm)
HD / VD:1.0 - 5.0 Vp-p (high impedance)
AUDIO Stereo mini jack (M3) ×1 0.5 Vrms, Shared with DVI-D IN
SERIAL External Control Terminal
D-sub 9 Pin RS-232C compatible
Sound
Speakers 50 mm ×90 mm ×2 pcs
Audio Output 10 W [5 W + 5 W] (10 % THD)
Accessories Supplied
Remote Control Transmitter N2QAYB000535
Batteries R6 Size ×2
Clamper TMME289 ×3
Dimensions (W ×H ×D) 968 mm ×561 mm ×101 mm (42 inch) 1,079 mm ×624 mm ×101 mm (47 inch)
Mass (weight) approx. 18.0 kg (42 inch) approx. 23.0 kg (47 inch)
Note:
• Design and specifications are subject to change without notice. Mass and dimensions shown are approximate.

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5 Operating Instructions

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