LG 42PC56 User manual

PLASMA TV
SERVICE MANUAL
CAUTION
BEFORE SERVICING THE CHASSIS,
READ THE SAFETY PRECAUTIONS IN THIS MANUAL.
CHASSIS : PD73A
MODEL : 42PC56 42PC56-ZD
website:htt ://biz.LGservice.com

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CONTENTS
SAFETY PRECAUTIONS ....................................................................................3
SPECIFICATIONS ................................................................................................4
ADJUSTMENT INSTRUCTIONS .........................................................................6
TROUBLE SHOOTING GUIDE..........................................................................19
BLOCK DIAGRAM.............................................................................................29
EXPLODED VIE ..............................................................................................30
EXPLODED VIE PARTS LIST ........................................................................31
REPLACEMENT PARTS LIST...........................................................................32
SCHEMATIC DIAGRAM.........................................................................................
PRINTED CIRCUIT DIAGRAM ..............................................................................

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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 sh uld be replaced with the same c mp nents as rec mmended in this manual t prevent
X-RADIATION, Sh ck, Fire, r ther Hazards.
D n t m dify the riginal design with ut permissi n f manufacturer.
General Guidance
An isolation Transformer should always be used during the
servicing f a receiver wh se chassis is n t is lated fr m the AC
p wer line. Use a transf rmer f adequate p wer rating as this
pr tects the technician fr m accidents resulting in pers nal injury
fr m electrical sh cks.
It will als pr tect the receiver and it's c mp nents fr m being
damaged by accidental sh rts f the circuitry that may be
inadvertently intr duced during the service perati n.
If any fuse ( r Fusible Resist r) in this m nit r is bl wn, replace it
with the specified.
When replacing a high wattage resist r (Oxide Metal Film Resist r,
ver 1W), keep the resist r 10mm away fr m PCB.
Keep wires away fr m high v ltage r high temperature parts.
Due t high vacuum and large surface area f picture tube,
extreme care sh uld be used in handling the Picture Tube.
D n t lift the Picture tube by it's Neck.
Leakage Current Cold Check(Antenna Cold Check)
With the instrument AC plug rem ved fr m AC s urce, c nnect an
electrical jumper acr ss the tw AC plug pr ngs. Place the AC
switch in the n p siti n, c nnect ne lead f hm-meter t the AC
plug pr ngs tied t gether and t uch ther hm-meter lead in turn t
each exp sed metallic parts such as antenna terminals, ph ne
jacks, etc.
If the exp sed metallic part has a return path t the chassis, the
measured resistance sh uld be between 1MΩ and 5.2MΩ.
When the exp sed metal has n return path t the chassis the
reading must be infinite.
An ther abn rmality exists that must be c rrected bef re the
receiver is returned t the cust mer.
Leakage Current Hot Check (See below Figure)
Plug the AC c rd directly int the AC utlet.
Do not use a line Isolation Transformer during this check.
C nnect 1.5K/10watt resist r in parallel with a 0.15uF capacit r
between a kn wn g d earth gr und (Water Pipe, C nduit, etc.)
and the exp sed metallic parts.
Measure the AC v ltage acr ss the resist r using AC v ltmeter
with 1000 hms/v lt r m re sensitivity.
Reverse plug the AC c rd int the AC utlet and repeat AC v ltage
measurements f r each exp sed metallic part. Any v ltage
measured must n t exceed 0.75 v lt RMS which is c rresp nds t
0.5mA.
In case any measurement is ut f the limits specified, there is
p ssibility f sh ck hazard and the set must be checked and
repaired bef re it is returned t the cust mer.
Leakage Current Hot Check circuit
1.5 K hm/10W
T Instrument's
exp sed 
METALLIC PARTS
G d Earth Gr und
such as WATER PIPE,
CONDUIT etc.
AC V lt-meter
IMPORTANT SAFETY NOTICE
0.15uF

SPECIFICATIONS
NOTE : Specifications and others are subject to change without notice for improvement .
VApplication Range
This spec is applied to the 42” PL SM TV used PD73 Chassis.
V Specification
Each part is tested as below without special appointment.
1) Temperature : 25±5°C (77±9°F), CST : 40±5
2) Relative Humidity: 65±10%
3) Power Voltage: Standard Input voltage (100-240V~, 50/60Hz)
* Standard Voltage of each product is marked by models.
4) Specification and performance of each parts are followed each drawing and specification by part number in accordance with SBOM.
5) The receiver must be operated for about 20 minutes prior to the adjustment.
VTest Method
1) Performance : LGE TV test method followed.
2) Demanded other specification
Safety : CE, IEC specification
EMC : CE, IEC
VGeneral Specification
1. Mod le Specification ( 42” XGA MODULE )
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Display Screen Device
spect Ratio
PDP Module
Operating Environment
Storage Environment
Input Voltage
1
2
3
4
5
6
No Item Specification Remark
42” Wide Color Display Module
16:9
PDP42X4,
RGB Closed Type, Film Filter
1)Temp. : 0~40deg
2)Humidity : 20~80%
3)Temp. : -20~60deg
4)Humidity : 10~90%
100-240V~, 50/60Hz
Plasma Display Panel
LGE SPEC.
Maker LG
Chassis
PD73 42PC56-ZD UK, German, Italy, France, Sweden, Finland, Spain LG
Model Name Market Brand Remark
42PC56-ZD
Safety : IEC/EN60065
EMI : EN55013
EMS : EN55020
UK, German, Italy, France, Sweden, Finland, Spain TEST
Model pplianceMarket Remark

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2. Model General Specification
Market
Br adcasting system
Receiving system
Scart Jack (2EA)
Vide Input (1EA)
S-Vide Input (1EA)
C mp nent Input (1EA)
RGB Input(1EA)
HDMI Input(2EA)
Audi Input (3EA)
1
2
3
4
5
6
7
8
9
10
N Item Specificati n Remark
UK, German, Italy, France, Sweden, Finland, Spain
1) PAL-BG
2) PAL-DK
3) PAL-I,I’
4) DVB-T(ID TV)
5) SECAM-L/L’
Anal g : Upper Heter dyne
Digital : COFDM
PAL, SECAM
PAL, SECAM, NTSC
PAL, SECAM, NTSC
Y/Cb/Cr, Y/Pb/Pr
RGB-PC
HDMI-DTV & SOUND
PC Audi , C mp nent, AV
4 System : PAL, SECAM, NTSC, PAL60
4 System : PAL, SECAM, NTSC, PAL60
L/R Input