Text preview for : LG_50PX4D_DF-054B_[SM].pdf part of LG LG 50PX4D DF-054B [SM] LG Monitor LG_50PX4D_DF-054B_[SM].pdf



Back to : LG_50PX4D_DF-054B_[SM].pd | Home

website:http://biz.LGservice.com
e-mail:http://www.LGEservice.com/techsup.html




PLASMA TV
SERVICE MANUAL
CHASSIS : DF-054B

MODEL : 50PX4D
50PX4D-EB

CAUTION
BEFORE SERVICING THE CHASSIS,
READ THE SAFETY PRECAUTIONS IN THIS MANUAL.
CONTENTS




SAFETY PRECAUTIONS ....................................................................................3

DESCRIPTION OF CONTROLS ..........................................................................4

SPECIFICATIONS ................................................................................................8

ADJUSTMENT INSTRUCTIONS .......................................................................10

TROUBLE SHOOTING GUIDE ..........................................................................15

PRINTED CIRCUIT DIAGRAM ..........................................................................24

BLOCK DIAGRAM .............................................................................................28

EXPLODED VIEW ..............................................................................................30

EXPLODED VIEW PARTS LIST ........................................................................31

REPLACEMENT PARTS LIST...........................................................................32

SCHEMATIC DIAGRAM.........................................................................................

PRINTED CIRCUIT BOARD ..................................................................................




- 2 -
SAFETY PRECAUTIONS

IMPORTANT SAFETY NOTICE
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.



General Guidance Leakage Current Hot Check (See below Figure)
Plug the AC cord directly into the AC outlet.
An isolation Transformer should always be used during Do not use a line Isolation Transformer during this check.
the servicing of a receiver whose chassis is not isolated from Connect 1.5K/10watt resistor in parallel with a 0.15uF capacitor
the AC power line. Use a transformer of adequate power rating between a known good earth ground (Water Pipe, Conduit, etc.)
as this protects the technician from accidents resulting in and the exposed metallic parts.
personal injury from electrical shocks. Measure the AC voltage across the resistor using AC
voltmeter with 1000 ohms/volt or more sensitivity.
It will also protect the receiver and it's components from being Reverse plug the AC cord into the AC outlet and repeat AC
damaged by accidental shorts of the circuitry that may be voltage measurements for each exposed metallic part. Any
inadvertently introduced during the service operation. voltage measured must not exceed 0.75 volt RMS which is
corresponds to 0.5mA.
If any fuse (or Fusible Resistor) in this monitor is blown, replace In case any measurement is out of the limits specified, there is
it with the specified. possibility of shock hazard and the set must be checked and
repaired before it is returned to the customer.
When replacing a high wattage resistor (Oxide Metal Film
Resistor, over 1W), keep the resistor 10mm away from PCB.

Keep wires away from high voltage or high temperature parts. Leakage Current Hot Check circuit

Due to high vacuum and large surface area of picture tube,
AC Volt-meter
extreme care should be used in handling the Picture Tube.
Do not lift the Picture tube by it's Neck.

Good Earth Ground
such as WATER PIPE,
Leakage Current Cold Check(Antenna Cold Check) To Instrument's CONDUIT etc.
With the instrument AC plug removed from AC source, 0.15uF
exposed
connect an electrical jumper across the two AC plug prongs. METALLIC PARTS
Place the AC switch in the on position, 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 1.5 Kohm/10W
antenna terminals, phone jacks, etc.
If the exposed metallic part has a return path to the chassis, the
measured resistance should be between 1M and 5.2M.
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.




- 3 -
DESCRIPTION OF CONTROLS



D/A TV POWER
selects analogue or digital mode. switches the set on from standby or off to
standby.
MODE
Selects another device. INPUT
D/A TV INPUT
Selects the TV, AV, Component, RGB or
GUIDE POWER HDMI modes.
shows a programme schedule. switches the set on from standby.
(In Digital mode only) TV
DVD
VCR
MODE

VCR BUTTONS GUIDE
ARC
Brings up the menu to select the Photo or
Controls a video cassette recorder. Music mode of Xstudio for memory cards.
These buttons are used for X-Studio.
For further details, see the `X-Studio' section.
ARC
INFO INFO i MARK Changes the picture format.
displays information on top of the screen TEXT
U EXIT
whilst watching the TV. MEN MARK
(In Digital mode only) Selects the wanted functions.
MENU
Displays on screen menus one by one. EXIT
OK
Exits the current menu. Clears all on-screen displays and returns
Memorizes menu changes. to TV viewing from any menu.

TEXT OK
These buttons are used for teletext. accepts your selection or displays the
For further details, see the `Teletext' section. current mode.
COLOURED BUTTONS : These buttons are
used for teletext (only TELETEXT models) D / E or F / G
or programme edit. VOL MUTE FAV PR
Adjusts menu settings.
Selects menu item.
VOL D / E (Volume Up/Down)
Increases/decreases sound level. FAV
PR D / E (Programme Up/Down) selects a favourite programme.
Selects a programme.

MUTE NUMBER buttons
Switches the sound on or off.
Q.VIEW
LIST Returns to the previously viewed
Displays the programme table. LIST Q.VIEW
programme.
PIP SIZE UPDATE INDEX STILL
Switches the sub picture on or off. I/II
Selects PIP or DW modes. TIME REVEAL MIX I/II
selects the sound output or the audio
PIP PR + /- ? M mode.
Selects a programme for the sub picture. PIP PR- PIP PR+ SWAP PIP INPUT

SWAP SLEEP
Alternates between main and sub picture. PIP M/C EJECT SLEEP APM
Sets the sleep timer.
PIP INPUT
Selects the input mode for the sub picture.
APM (Adaptive Picture Mode)
Concurrently, compare with the Dynamic,
M/C EJECT Standard, Mild and User on the screen.
Remove the Memory Card.




LIGHT
Illuminates the remote control
buttons of selected
mode.




- 4 -





9




7

8




INPUT MENU OK VOL PR




1 2 3 4 5 6




1. Power Button 6. D / E (Programme Up/Down)
Switches the set on from standby or off to standby. Selects a programme or a menu item.
Switches the set on from standby.
2. Remote Control Sensor
F / G (Volume Up/Down)
3. INPUT Button Adjusts the volume.
Selects the TV, AV, Component, RGB or HDMI modes. Adjusts menu settings.
Switches the set on from standby.
7. Power Indicator
4. MENU Illuminates red in standby mode, Illuminates green when the
Displays on screen menus one by one. set is turned on
Exits the current menu.
8. Intelligent Eye
Memorizes menu changes.
Adjusts picture according to the surrounding conditions.
5. OK
9. Memory Card Slots 1, 2
Accepts your selection or displays the current mode.




- 5 -





AV5
S-VIDEO




VIDEO
11




L/MONO AUDIO
R
AC INPUT




1 2 3 4 5 6 7 8 9 10



1. PCMCIA (Personal Computer Memory Card 8. COMPONENT INPUT
International Association) Card Slot Connect DVD video outputs to Y, PB, PR of COMPONENT
INPUT and audio outputs to Audio sockets of AUDIO
2. ANTENNA INPUT/OUTPUT INPUT.
3. HDMI(DVI VIDEO) / AUDIO INPUT / RGB INPUT 9. EURO SCART SOCKET
Connect the monitor output socket of the PERSONAL Connect the euro scart socket of the VCR to these sockets.
COMPUTER to this socket.
Note:
Note: If you want to use RGB/DVI audio, we strongly a. If you want to use the EURO scart cable, you have to
recommend that you use the cable that has a core, or the use the signal shielded Euro scart cable.
EMI Filter core along with separate cable. b. If the S-VIDEO(Y/C) signal is received through the Euro
4. REMOTE CONTROL scart socket 2 (AV2), you must change to the SAV2 mode.
5. VARIABLE AUDIO OUT SOCKETS 10. POWER CORD SOCKET
This set operates on AC power. The voltage is indicated on
6. RS-232C INPUT (CONTROL/SERVICE) PORT the Specifications page. Never attempt to operate the
Connect to the RS-232C port on a PC. Monitor on DC power.
7. AUDIO/VIDEO IN SOCKETS (AV4) 11. AUDIO/VIDEO IN SOCKETS (AV5)
Connect the audio/video out sockets of external equipment S-VIDEO/AUDIO IN SOCKETS
to these sockets.
S-VIDEO/AUDIO IN SOCKETS
Connect the S-VIDEO out socket of an VCR to the S-VIDEO
socket.
Connect the audio out sockets of the VCR to the audio
sockets as in AV4.


- 6 -
Accessories
D/A TV INPUT

POWER

DVD
TV VCR
MODE
ARC
GUIDE




INFO i MARK



U TEXT EXIT
MEN




OK




VOL MUTE FAV PR




LG TV
LIST Q.VIEW


SIZE UPDATE INDEX STILL
AS mark
TIME REVEAL MIX I/II
? M

PIP PR- PIP PR+ SWAP PIP INPUT



PIP M/C EJECT SLEEP APM




Owner's Manual Remote Control handset 2-Eye Bolts




1.5V
1.5V


Alkaline batteries Power Cord 2-Wall brackets




Joining the set assembly to the wall to prevent the set tumbling
- Secure the set assembly by fixing it to a wall by using the Eye Bolts/Wall brackets.