LG 20lc1r Service Manual

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9. Preset CH information
PIF[MHz] SYSTEM VideoSound
TXT NAME
System Mode
LGE KUMI PR 0 45.25  PAL-BG PHILIPS MONO C 01
PR 1 575.25  SECAM-DK DIGITAL DUAL C 34
PR 2 175.25  PAL-BG PHILIPS STEREO FLOF C 05
PR 3 231.25  PAL-I FUBK MONO S 11
PR 4 675.25  NTSC-M DIGITAL MONO C 48
PR 5 62.25  SECAM-BG PHILIPS DUAL C 04
PR 6 189.25  PAL-BG Crosshatch NICAM DUAL FLOF C 07
PR 7 703.25  PAL-BG RGB, WHITE MONO C 50
PR 8 719.25  PAL-BG MATRIX C/B NICAM STEREO C 52
PR 9 631.25  PAL-I PHILIPS NICAM STEREO C 41...

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1. Application
This document is applied to 20.1 LCD TV which is
manufactured in Monitor Factory or is produced on the basis
of this data. 
2.  Designation
2.1 The adjustment is according to the order which is
designated and which must be followed, according to the
plan  which can be changed only on agreeing.
2.2. Power Adjustment : Free Voltage
2.3. Magnetic Field Condition: Nil.
2.4. Input signal Unit : Product Specification Standard 
2.5. Reserve after operation : Above 30 Minutes 
2.6....

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3.2 Total Assembly line process
3.2.1 Adjustment Preparation
IIC_SW should set to 0
Above 30 minutes H/run in RF no signal
3.2.2 Confirmation of Luminance
Set Statement
Input : AV2
PSM : Dynamic
CSM : Normal
Signal equipment displays
Output Voltage  :  700  mVp-p
Output Mode    :  Full White pattern
Confirm whether luminance is over  350 cd/m2  or not
3.2.3 Confirmation of Color Coordinate
Input Full White Pattern (AV2-CVBS)
Set CSM : Normal (9300K)
Confirm whether x=0.283±0.03, y=0.298±0.03 or...

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SVC REMOCON
NO. KEY FUNTION REMARK
1 POWER To turn the TV on or off
2 MUTE To activate the mute function.
3 P-CHECK To check TV screen image easily. Shortcut keys
4 S-CHECK To check TV screen sound easily Shortcut keys
5 ARC(23inch) To select size of the main screen  Shortcut keys
(Auto, 4:3, 16:9, 14:3, Zoom, Cinema Zoom)
6 CAPTION Switch to closed caption broadcasting
7 TXT To toggle on/off the teletext mode
8 TV/AV External input
9 IN-START To enter adjustment mode when manufacturing the TV...

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TROUBLESHOOTING
No power 
(LED indicator off)
Check short of main B/D 
or Change Lips
Change U406
Change LED Assy
Check 15V or 5V 
of Lips
Check Output of 
U406
Check LED Assy
Check J103, J125, J126
Connector 
Fail
Fail
Change Q402Check Output of 
Q402
Fail
Pass
Fail
Pass
Pass
Pass
:[A]Process
 

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No Raster
Check LED Status 
on display unit
Check the input/
Output of U301
Check 
U401~U405, U407, U409
Check inverter
Connector or inverter
Check input source cable and jack 
Repeat A PROCESSFail
Change U401~U405,
U407, U409
Fail
Change U301Fail
Change inverter
connector or inverter
Fail
Change panel link
cable or module
Fail Check panel link 
Cable or module
Pass
Pass
Pass
Pass
Pass
:[B]Process
 

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No Raster on AV Signal
(SCART, CVBS, S-VHS)No Raster on TV(RF) signal
Change L108, L109, 
L110, L112, R194, R198,
R184Check the signal of 
L108, L109, L110, L112
R194, R198, R184
Repeat
[A] Process Check the output of 
TU701
Check the
input/output  of U301
Check the 
input/output of U101
Check input source cable and  jack 
Fail
FailFail
Fail
Re-soldering or
Change the defect part
Check X301
Fail
Re-soldering or
Change the defect part
Check 5V, 33V of TU701
Re-soldering or 
Change the defect part...

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No Sound
Check the speaker wire
Change source inputCheck the 
input source
Fail
Pass
Re-soldering or 
Change the defect part
Check X301Check the input/output 
of U301
Fail
Pass
Re-soldering or 
Change the defect partCheck the input/output 
of U201
Fail
Pass
Change speakerCheck the speakerFail
Pass
 

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BLOCK DIAGRAM
 
 

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BLOCK DIAGRAM DESCRIPTION
Power Supply Block (LIPS)
This Block Generates DC Voltage (5V,15V) to Main
Control system from AC Power (100-240 V, 50/60 Hz,
1.0A)
Also it has the inverter function that converts input
voltage to AC Rms value for the LCD lamp.
DC/DC Converter block 
DC/DC Converter convert the input 5V,15V to proper
3.3V, 5V, 8V, 12V for Main control system.
For shooting heat trouble, we use the DC/DC
converting IC
Audio Amplifier
This block is composed of TPA3005D2 and peripheral...