Panasonic VIERA TH-P42A20M User manual

© Panasonic Corporation 2010.
Unauthorized copying and distribution is a violation
of law.
ORDER NO.PSG1003029CE
Plasma Television
Model No. TH-P42A20M
TH-P42A20P
GPH13DA Chassis
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TABLE OF CONTENTS
PAGE PAGE
1 Safety Precautions -----------------------------------------------3
1.1. General Guidelines ----------------------------------------3
1.2. Touch-Current Check--------------------------------------3
2Warning--------------------------------------------------------------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. PCB Layout --------------------------------------------------6
3.2. Applicable signals------------------------------------------7
4 Specifications ------------------------------------------------------8
5 Service Mode ----------------------------------------------------- 10
5.1. How to enter into Service Mode ---------------------- 10
5.2. Option - Mirror--------------------------------------------- 12
5.3. Service tool mode---------------------------------------- 12
5.4. Hotel mode------------------------------------------------- 13
5.5. Data Copy by SD Card --------------------------------- 14
6 Troubleshooting Guide---------------------------------------- 17
6.1. Check of the IIC bus lines------------------------------ 17
6.2. Power LED Blinking timing chart --------------------- 18
6.3. No Power--------------------------------------------------- 19
6.4. No Picture-------------------------------------------------- 20
6.5. Local screen failure-------------------------------------- 21
7 Disassembly and Assembly Instructions --------------- 22
7.1. Remove the Rear cover -------------------------------- 22
7.2. Remove the AC inlet ------------------------------------ 22
7.3. Remove the P-Board------------------------------------ 22
7.4. Remove the Side terminal cover and the Side
shield metal ------------------------------------------------ 22
7.5. Remove the Tuner unit --------------------------------- 23
7.6. Remove the A-Board------------------------------------ 23
7.7. Remove the Speakers ---------------------------------- 23
7.8. Remove the SN-Board---------------------------------- 23
7.9. Remove the SS-Board---------------------------------- 24
7.10. Remove the Hanger metals and the Stand
brackets----------------------------------------------------- 24
7.11. Remove the C1-Board ---------------------------------- 24
7.12. Remove the C2-Board ---------------------------------- 24
7.13. Remove the Plasma panel section from the
Cabinet assy (glass)------------------------------------- 25
7.14. Remove the Glass holders ---------------------------- 25
7.15. Remove the K-Board------------------------------------ 25
7.16. Replace the plasma panel ----------------------------- 26
8 Measurements and Adjustments -------------------------- 27
8.1. Adjustment ------------------------------------------------- 27
9 Block Diagram --------------------------------------------------- 31
9.1. Main Block Diagram ------------------------------------- 31
9.2. Block (1/4) Diagram ------------------------------------- 32
9.3. Block (2/4) Diagram ------------------------------------- 33
9.4. Block (3/4) Diagram ------------------------------------- 34
9.5. Block (4/4) Diagram ------------------------------------- 35
10 Wiring Connection Diagram --------------------------------- 37
10.1. Caution statement.--------------------------------------- 37
10.2. Wiring (1) --------------------------------------------------- 37
10.3. Wiring (2) --------------------------------------------------- 38
10.4. Wiring (3) --------------------------------------------------- 38
10.5. Wiring (4) --------------------------------------------------- 39
11 Schematic Diagram--------------------------------------------- 41
11.1. Schematic Diagram Note ------------------------------ 41
11.2. P-Board (1/4) Schematic Diagram ------------------ 42
11.3. P-Board (2/4) Schematic Diagram ------------------ 43
11.4. P-Board (3/4) Schematic Diagram ------------------ 44
11.5. P-Board (4/4) Schematic Diagram ------------------ 45
11.6. A-Board (1/13) Schematic Diagram----------------- 46
11.7. A-Board (2/13) Schematic Diagram----------------- 47
11.8. A-Board (3/13) Schematic Diagram----------------- 48
11.9. A-Board (4/13) Schematic Diagram----------------- 49
11.10. A-Board (5/13) Schematic Diagram----------------- 50
11.11. A-Board (6/13) Schematic Diagram----------------- 51
11.12. A-Board (7/13) Schematic Diagram----------------- 52
11.13. A-Board (8/13) Schematic Diagram----------------- 53
11.14. A-Board (9/13) Schematic Diagram----------------- 54
11.15. A-Board (10/13) and K-Board Schematic
Diagram ---------------------------------------------------- 55
11.16. A-Board (11/13) Schematic Diagram --------------- 56
11.17. A-Board (12/13) Schematic Diagram --------------- 57
11.18. A-Board (13/13) Schematic Diagram --------------- 58
11.19. C1-Board Schematic Diagram ----------------------- 59
11.20. C2-Board Schematic Diagram ----------------------- 60
11.21. SN-Board (1/9) Schematic Diagram ---------------- 61
11.22. SN-Board (2/9) Schematic Diagram ---------------- 62
11.23. SN-Board (3/9) Schematic Diagram ---------------- 63
11.24. SN-Board (4/9) Schematic Diagram ---------------- 64
11.25. SN-Board (5/9) Schematic Diagram ---------------- 65
11.26. SN-Board (6/9) Schematic Diagram ---------------- 66
11.27. SN-Board (7/9) Schematic Diagram ---------------- 67
11.28. SN-Board (8/9) Schematic Diagram ---------------- 68
11.29. SN-Board (9/9) Schematic Diagram ---------------- 69
11.30. SS-Board (1/2) Schematic Diagram ---------------- 70
11.31. SS-Board (2/2) Schematic Diagram ---------------- 71
12 Printed Circuit Board------------------------------------------ 72
12.1. P-Board ---------------------------------------------------- 72
12.2. K-Board ---------------------------------------------------- 75
12.3. A-Board ---------------------------------------------------- 76
12.4. C1-Board--------------------------------------------------- 78
12.5. C2-Board--------------------------------------------------- 79
12.6. SN-Board -------------------------------------------------- 80
12.7. SS-Board -------------------------------------------------- 82
13 Exploded View and Replacement Parts List----------- 85
13.1. Exploded View and Mechanical Replacement
Parts List --------------------------------------------------- 85
13.2. Electrical Replacement Parts List ------------------- 92
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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 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 (TOUGH 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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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 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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