LG 42LB4D, Training Manual

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Directview LCD Training
3
Contents
TAblE OF CONTENTS
OVERVIEW ....................................................................................................5
INTRODUCTION .................................................................................................... 5
COMPUTER CONNECTION ........................................................................................ 5
MODEL NUMBER STRUCTURE ................................................................................... 5
SERIAL NUMBER STRUCTURE .................................................................................. 6
SERVICE MENU ..................................................................................................... 6
SERVICE REMOTE .................................................................................................. 7
THEORy .......................................................................................................9
LIqUID CRySTAL DISPLAy ...................................................................................... 9
LIqUID CRySTAL PANEL ........................................................................................10
TROUBLESHOOTING - POWER ......................................................................... 11
POWER SUPPLy ...................................................................................................11
PSU CONNECTORS ................................................................................................11
PSU BALLAST CONNECTORS ...................................................................................12
PSU CONNECTORS - FULL LIST ................................................................................13
IC DISTRIBUTION CHART ......................................................................................14
I
2
C BUS DATA CONTROL LINES ................................................................................15
POWER SUPPLy FLOWCHART ..................................................................................16
TROUBLESHOOTING - VIDEO .......................................................................... 17
VIDEO BLOCk DIAGRAM ........................................................................................17
NO VIDEO FLOWCHART .........................................................................................18
LCD CONTROL BOARD ...........................................................................................19
NO RF - VIDEO FLOWCHART ...................................................................................21
NO RF - NTSC ......................................................................................................22
NO RF - ATSC ......................................................................................................23
AV1/AV2 AUDIO ..................................................................................................24
COMPOSITE VIDEO INPUT......................................................................................25
COMPONENT VIDEO INPUT ....................................................................................26
COMPONENT INPUT FLOWCHART .............................................................................27
RGB VIDEO INPUT ...............................................................................................28
HDMI SIGNAL PATH .............................................................................................29
COMPONENT/RGB FLOWCHART ...............................................................................30
DEFECTIVE VIDEO FLOWCHART ...............................................................................31
TROUBLESHOOTING - AUDIO .......................................................................... 32
AUDIO SIGNAL PATH ............................................................................................32
NO AUDIO OUT FLOWCHART ..................................................................................33
NO RF SOUND .....................................................................................................34
NO RF SOUND FLOWCHART ....................................................................................35
NO DTV SOUND ...................................................................................................36
NO SOUND FROM INPUTS ......................................................................................37
NO HDMI SOUND .................................................................................................38
USB MEDIA DEVICE FLOWCHART .............................................................................39
DISASSEMBLy.............................................................................................. 40
ExPLODED VIEW ..................................................................................................40
ExPLODED VIEW PARTS .........................................................................................41