SERVICE MANUAL
CHASSIS  LD21B
READ THE SAFETY PRECAUTIONS IN THIS MANUAL
http//aic.lgservice.com
 SAFETY PRECAUTIONS
CONTENTS
SERVICING PRECAUTIONS
SPECIFICATION
 IMPORTANT SAFETY NOTICE
SAFETY PRECAUTIONS
 Electrostatically Sensitive ES Devices
SERVICING PRECAUTIONS
 Replacement
IC Remove/Replacement
Small-Signal Discrete Transistor Removal/Replacement
Removal
 4. Model General Specification
SPECIFICATION
1. Application range
3. Test method
 symbolrate
Symbolrate  4.0Msymbols/s to 7.2Msymbols/s
DVB-S2 8PSK / QPSK  2 ~ 45Msymbol/s
DVB-S QPSK  2 ~ 45Msymbol/s
 5. Video resolutions 2D
5.1. Component Input Y, CB/PB, CR/PR
5.2. RGB Input PC
 PCDVI
5.3. HDMI InputPC/DTV
 Boot file Download
ADJUSTMENT INSTRUCTION
1. Application Range
2. Designation
 3.3. EDID data
3.1. ADC Process
3.2. EDID Download
7. ADC Calibration
 4. Total Assembly line process
4.1. Adjustment Preparation
3.4 Function Check
 6.1. Signal Table
4.3. Outgoing condition Configuration
5. HI-POT Test
6. Model name & Serial number D/L
 6.3. Method & notice
7. MAC Address & CI+ key download
7.1 MAC Address
GP4LOW
 7.3. LAN PORT INSPECTIONPING TEST
7.2 LAN Inspection
 Screw specification and application situation
SCREW ASSEMBLY WORKING GUIDE
ח ͷͲͳͤͤͤͪͥͣ͢͡ ͙;ͤ͛ͽͥͦ͑͟͝ͳͼ͑͝;ΒΔΙΚΟΖ͚ ח ͣ͢ͶͲ
ח ͷͲͳͤͨͩͩͣ͑͢͡͡ ͙;ͧ͛ͽ͑͢͡͝ͳͼ͑͝;ΒΔΙΚΟΖ͚
 Rear
BLOCK DIAGRAM
Side
LG2111 A
 EXPLODED VIEW
 Copyright  2012 LG Electronics. Inc. All rights reserved
GP4LS7LR22011.12.01
to delete CI or gate for
for SYSTEM EEPROM
 VDDC
Normal Power
Normal
DDR3
 PowerDET
FROM LIPS & POWER B/D
+3.3VNormal
+1.5VDDR
 IR/LED and control for normal models
 USB SIDE
USB1DIODES
USB2DIODES
 HDMI
 THE  SYMBOL MARK OF THIS SCHEMETIC DIAGRAM INCORPORATES
RGB-PC / SPDIF
SPECIAL FEATURES IMPORTANT FOR PROTECTION FROM X-RADIATION
FILRE AND ELECTRICAL SHOCK HAZARDS, WHEN SERVICING IF IS
 RS-232C
COMMERCIAL/NonOS MODEL OPTION COMMERCIAL MODEL OPTION
For Comsumer model, use 4PIN Wafer
 LVDS for large inch
 GP4LS7LR22011/06/03 DDR25612
S7LR2DIVXMS10
IC1201
H5TQ1G63DFR-H9C
 Serial Flash for SPI boot
SFLASHMAINMACRONIX
SFLASHMAINWINBOND IC1401-*1 W25Q80BVSSIG
 Headphone *Option  HEADPHONE
PHONE
HEAD
 CI Region
Option name of this page CISLOT because of Hong Kong
10067972-0500LF
 H/W option  ETHERNET
GP4LS7LR22011/06/14 ETHERNET21
ETHERNET
 TU2602TU2603 TDSS-G101D TDSN-G301D
GP4RGLOBALTUNERBLOCK
TU2601
TDSQ-G001D
 OptionLNB
DVB-S2 LNB Part Allegro
GP4LS7LR22011/11/02 DVBS27
DCDCGND and AGND are connected
 FULL SCART / COMPONENT1
SCART / COMPONENT&COMPSIT
JK2801
PSC008-01
 AUDIO AMPSTA380BWE
Page
 Contents of LCD TV Standard Repair Process
 Continue to the next page
Contents of LCD TV Standard Repair Process Detail Technical Manual
Error symptom
Content
 LCD TV
A. Video error
Main B/D↔ Power B/D, LVDS Cable,Speaker Cable,IR B/D Cable
A2 Check Power Board 24v output
 Check various
voltages of Power
Board  3.5V,12V,20V
or 24V…
 By using Digital signal level meter By using Diagnostics menu on OSD
Menu→ Set up→ Support → Signal Test Signal strength Normal  over 50%
Signal Quality Normal over 50%
 → Set-Top-Box, Different maker TV etc
 Check color by input -External Input COMPONENT -RGB
A8/ A9
※ Check
Link Cable
 Vertical/Horizontal bar, residual image, light spot
External device screen error-Color error
Connect other external device and cable
Check color condition by input -External Input -Component RGB
 Check Power LED
B. Power error
Check Power On ‘”High”
Measure voltage of each output of Power B/D
 If Power Off mode is not displayed Check Power B/D voltage
Check Power Off Mode
POWEROFFABNORMAL1
POWEROFFCPUABNORMAL
 24V of Power
C. Audio error
Check user menu  Speaker off
Check audio B+
 Check audio B+ Voltage
In case of External Input signal error Check and fix external device
 D. Function error
1. Remote controlR/C operating error
Check & Repair
 Y Check technical Signal information input? - Fix information
Check input signal
Recognition error
Replace Main B/D
 Identify nose type
E. Noise
 F. Exterior defect