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LG Electronics L1933TR, L1733TR service manual Troubleshooting Guide, No Power, Waveforms

Models: L1733TR L1933TR

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TROUBLESHOOTING GUIDE

1. NO POWER

NO POWER

(POWER INDICATOR OFF)

Check J403 Voltage		NO


Pin5, Pin6 (5V)?

	YES


Check		NO
U301 Pin2 Voltage		NO


(3.3V) ?

	YES


Check Key Control
Connector Routine

Check Power Board,

And Find Out a Short Point

as Opening

Each Power Line

Check 3.3V Line

(Open Check)

No Problem

Is U201

Pin75 (3.3V)

Voltage ?

	YES
		NO

Check U201 Pin 96
Check U201 Pin 96
Pulse

	YES


Check U201

Check 3.3V Line

Check X-TAL

Waveforms

U201-#96

Copyright 2007 LG Electronics. Inc. All right reserved.	LGE Internal Use Only
Only for training and service purposes	- 18 -
Only for training and service purposes

Page 18

Image 18

LG Electronics L1933TR, L1733TR service manual Troubleshooting Guide, No Power, Waveforms

Contents

CHASSIS NO. LM57B READ THE SAFETY PRECAUTIONS IN THIS MANUALSame model for Service BEFORE SERVICING THE UNITCONTENTS SPECIFICATIONSmarked on the schematic diagram and the PRECAUTIONWARNING FOR THE SAFETY-RELATEDCOMPONENT Leakage Current Hot Check CircuitSERVICING PRECAUTIONS General Servicing PrecautionsElectrostatically Sensitive ES Devices Small-SignalDiscrete Transistor IC Remove/ReplacementReplacement Removal/ReplacementCircuit Board Foil Repair At IC ConnectionsAt Other Connections TIMING CHART VIDEOSYNC Soft pad on the table DISASSEMBLY-SetOnly for training and service purposes Pull up the stand part1.Pull the front cover upward Only for training and service purposesRemove the screws 3.Put the front face downDISASSEMBLY-Stand In case of Latch #1-1Only for training and service purposes In case of Latch #1DISASSEMBLY-Stand Hold the stand bodyMStarACE BLOCK DIAGRAMLIPS Line BufferBLOCK DIAGRAM-POWER POWERINVERTER 1.Video Controller Part DESCRIPTION OF BLOCK DIAGRAM2.Power Part 3.MICOM PartPRIMARY LIPS Board Block Diagram6.Signal collection Operation description LIPSADJUSTMENT SERVICE OSD Figure 1. Cable ConnectionTROUBLESHOOTING GUIDE 1. NO POWERWaveforms 2. NO RASTER OSD IS NOT DISPLAYED - LIPS 3. NO RASTER OSD IS NOT DISPLAYED - MSTAR Waveforms4. TROUBLE IN DPM Waveforms5. POWER 6. Raster LGE Internal Use Only WIRING DIAGRAMOnly for training and service purposes 6631900109AEXPLODED VIEW Only for training and service purposesLGE Internal Use Only EXPLODED VIEW PARTS LIST Ref. NoDescription Only for training and service purposes REPLACEMENT PARTS LISTSAFETY Mark CAUTION: BEFORE REPLACING ANY OF THESE COMPONENTSFILTERs Only for training and service purposesLGE Internal Use Only TRANSISTORCAPACITORS Only for training and service purposesLGE Internal Use Only TRANSISTORs & ICsOnly for training and service purposes LGE Internal Use OnlyTRANSFORMER Only for training and service purposes SCHEMATIC DIAGRAM1. SCALER LGE Internal Use Only2. POWER & WAFER Only for training and service purposesLGE Internal Use Only 3. INVERTER Only for training and service purposesLGE Internal Use Only 4. POWER Only for training and service purposesLGE Internal Use Only Feb P/NO MFL43002807