LG 42PC3DD-UE (CHASSIS:PA73E) Service Manual ▷ View online
PLASMA TV
SERVICE MANUAL
SERVICE MANUAL
July, 2007
P/NO : MFL36737208
CHASSIS : PA73E
NS-PDP42
CAUTION
BEFORE SERVICING THE CHASSIS, READ THE SAFETY PRECAUTIONS IN THIS MANUAL.
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SAFETY PRECAUTIONS
Many electrical and mechanical parts in this chassis have special safety-related characteristics. These parts are identified by in
the Schematic Diagram and Replacement Parts List.
It is essential that these special safety parts should be replaced with the same components as recommended in this manual to
prevent X-RADIATION, Shock, Fire, or other Hazards.
Do not modify the original design without permission of manufacturer.
the Schematic Diagram and Replacement Parts List.
It is essential that these special safety parts should be replaced with the same components as recommended in this manual to
prevent X-RADIATION, Shock, Fire, or other Hazards.
Do not modify the original design without permission of manufacturer.
General Guidance
An lsolation Transformer should always be used during
the servicing of a receiver whose chassis is not isolated from
the AC power line. Use a transformer of adequate power rating
as this protects the technician from accidents resulting in
personal injury from electrical shocks.
the servicing of a receiver whose chassis is not isolated from
the AC power line. Use a transformer of adequate power rating
as this protects the technician from accidents resulting in
personal injury from electrical shocks.
It will also protect the receiver and it's components from being
damaged by accidental shorts of the circuitary that may be
inadvertently introduced during the service operation.
damaged by accidental shorts of the circuitary that may be
inadvertently introduced during the service operation.
If any fuse (or Fusible Resistor) in this monitor is blown, replace
it with the same specified type.
it with the same specified type.
When replacing a high wattage resistor (Oxide Metal Film
Resistor, over 1W), keep the resistor 10mm away from PCB.
Resistor, over 1W), keep the resistor 10mm away from PCB.
Keep wires away from high voltage or high temperature parts.
Leakage Current Cold Check(Antenna Cold Check)
With the instrument AC plug removed from AC source,
connect an electrical jumper across the two AC plug prongs.
Place the AC switch in the on positioin, connect one lead of
ohm-meter to the AC plug prongs tied together and touch other
ohm-meter lead in turn to each exposed metallic parts such as
antenna terminals, phone jacks, etc.
If the exposed metallic part has a return path to the chassis, the
measured resistance should be between 1MΩ and 5.2MΩ.
When the exposed metal has no return path to the chassis the
reading must be infinite.
An other abnormality exists that must be corrected before the
receiver is returned to the customer.
connect an electrical jumper across the two AC plug prongs.
Place the AC switch in the on positioin, connect one lead of
ohm-meter to the AC plug prongs tied together and touch other
ohm-meter lead in turn to each exposed metallic parts such as
antenna terminals, phone jacks, etc.
If the exposed metallic part has a return path to the chassis, the
measured resistance should be between 1MΩ and 5.2MΩ.
When the exposed metal has no return path to the chassis the
reading must be infinite.
An other abnormality exists that must be corrected before the
receiver is returned to the customer.
Leakage Current Hot Check
(See below Figure)
Plug the AC cord directly into the AC outlet.
Do not use a line Isolation Transformer during this check.
Connect 1.5K/10watt resistor in parallel with a 0.15uF capacitor
between a known good earth ground (Water Pipe, Conduit, etc.)
and the exposed metallic parts.
Measure the AC voltage across the resistor using AC
voltmeter with 1000 ohms/volt or more sensitivity.
Reverse plug the AC cord into the AC outlet and repeat AC
voltage measurements for each esposed metallic part. Any
voltage measured must not exceed 0.75 volt RMS which is
corresponds to 0.5mA.
In case any measurement is out of the limits sepcified, there is
possibility of shock hazard and the set must be checked and
repaired before it is returned to the customer.
Do not use a line Isolation Transformer during this check.
Connect 1.5K/10watt resistor in parallel with a 0.15uF capacitor
between a known good earth ground (Water Pipe, Conduit, etc.)
and the exposed metallic parts.
Measure the AC voltage across the resistor using AC
voltmeter with 1000 ohms/volt or more sensitivity.
Reverse plug the AC cord into the AC outlet and repeat AC
voltage measurements for each esposed metallic part. Any
voltage measured must not exceed 0.75 volt RMS which is
corresponds to 0.5mA.
In case any measurement is out of the limits sepcified, there is
possibility of shock hazard and the set must be checked and
repaired before it is returned to the customer.
Leakage Current Hot Check circuit
1.5 Kohm/10W
To Instrument's
exposed
METALLIC PARTS
exposed
METALLIC PARTS
Good Earth Ground
such as WATER PIPE,
CONDUIT etc.
such as WATER PIPE,
CONDUIT etc.
AC Volt-meter
IMPORTANT SAFETY NOTICE
0.15uF
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ADJUSTMENT INSTRUCTIONS ..........................................4
TROUBLESHOOTING GUIDE ............................................14
BLOCK DIAGRAM...............................................................19
EXPLODED VIEW...............................................................24
EXPLODED VIEW PARTS LIST .........................................25
REPLACEMENT PARTS LIST ............................................26
SCHEMATIC DIAGRAM..........................................................
PRINTED CIRCUIT BOARDS .................................................
TABLE OF CONTENTS
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ADJUSTMENT INSTRUCTIONS
1. Application Object
These instructions are applied to all of the PDP TV, PA73E.
2. Notes
(1) Because this is not a hot chassis, it is not necessary to use
an isolation transformer. However, the use of isolation
transformer will help protect test equipment.
transformer will help protect test equipment.
(2) Adjustments must be done in the correct order.
(3) The adjustments must be performed in the circumstance of
(3) The adjustments must be performed in the circumstance of
25±5°C of temperature and 65±10% of relative humidity if
there is no specific designation.
there is no specific designation.
(4) The input voltage of the receiver be must kept 110V, 60Hz
when adjusting.
(5) The receiver must be operational for about 15 minutes
prior to the adjustments.
O
Preliminary action is applied to the test for afterimage
discharge detection, and 100% FULL WHITE PATTERN
must be operated automatically.
must be operated automatically.
1) Pressing Power On key
2) Full Test Pattern(2 min 30sec)
3) Full Black Pattern(30sec)
4)Full White Pattern
2) Full Test Pattern(2 min 30sec)
3) Full Black Pattern(30sec)
4)Full White Pattern
O
Pattern Mode is deselected by pressing CH +/-, Exit Key.
[
Set is activated HEAT-RUN without signal generator in this
mode.
3. MICOM Download(Option)
3-1. Required Test Equipment
(1) JIG-LEVER TYPE for adjusting: 1EA
(2) PC & MONITOR: 2EA
(3) BOARD for INTERFACE: IIC & ISP BOARD: 2EA
(4) 15P D-SUB CABLE: 2EA
(5) Using the 12/15 line of D-SUB 15P
(2) PC & MONITOR: 2EA
(3) BOARD for INTERFACE: IIC & ISP BOARD: 2EA
(4) 15P D-SUB CABLE: 2EA
(5) Using the 12/15 line of D-SUB 15P
12-SDA/15-SCL
3-2. JIG Connection
3-3. Establishment Program
(1) Establish LGE Monitor Tools v1.1
(2) The program work and it is opened program window as
(2) The program work and it is opened program window as
seen below.
Test Pattern 2min 30sec
Test Pattern 30sec
If you turn on a still screen more than 20 minutes (Especially
Digital pattern(13 CH), Cross Hatch Pattern), an afterimage
may occur in the black level part of the screen.
Digital pattern(13 CH), Cross Hatch Pattern), an afterimage
may occur in the black level part of the screen.
connection
to PC
connection
to PC