Mitsubishi Electric LT-46244 User manual

• Design specifications are subject to change without notice.
MITSUBISHI DIGITAL ELECTRONICS AMERICA, INC.
9351JeronimoRoad,Irvine,CA 92618-1904
Copyright © 2007 Mitsubishi Digital ElectronicsAmerica, Inc.
AllRightsReserved
CAUTION:
Before servicing this chassis, it is important that the service person read the "SAFETY PRECAUTIONS" and
"PRODUCTSAFETYNOTICE" containedinthis manual.
SerSer
SerSer
Servicevice
vicevice
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ManualManual
ManualManual
Manual
20072007
20072007
2007
MITSUBISHIELECTRIC
LCD FLAT PANEL TELEVISION
VLP38 / VLP38+ / VLP38++ CHASSIS
•AVAnalog Inputs : VIDEOINJACK(RCAType)
& Outputs : AUDIOINJACK(RCAType)
: S-VIDEO IN JACK (Y/C separate)
: COMP/Y,Cr,Cb(RCAType)
: USB Input (5 meg pixel photo)
: Stereo Audio Outputs
• Inputs/Outputs : HDMITM 1.3 Inputs (digital)
480i, 480p, 720p, 1080i (60Hz)
1080p(24Hz, 30Hz, 60Hz)
: Digital Audio Output
(Dolby® Digital/PCM)
: IEEE-1394 I/O Jacks (V38++ only)
Dealer Playback Only
•HDMITM DigitalPCCompatibilty
: 640 x 480, 898 x 480, 800 x 600,
1064 x 600, 1024 x768, 1280 x 720,
1365 x 768, 1280 x 10s4 @ 60Hz
: 1920 x 1080 @ 24Hz, 30Hz, 60Hz
• Speakers : Two5½"x2¼"Oval
(4Ω 10W)
: Lead-Free solder PWBs
WD-52327
VLP38 Chassis
LT-40133
LT-46133
LT-52133
WD-52527
Pb Solder
Pb Solder
VLP38M Chassis
LT-40134
VLP38++ Chassis
LT-46244
LT-52244
SPECIFICATIONS
• Power Input : AC 120V, 60Hz
•Power Usage : See table on page 5
• Dimensions : See table on page 5
& Weight
• LCDPanel VLP38
: Resolution - 1920 x 1080
: Vertical Scan Range - 60Hz
VLP38+ / VLP38++
: Resolution - 1920 x 1080
: Vertical Scan Range - 120Hz
• Tuning : Digital/Analog Tuner
(NTSC/ATSC/QAM)
: Out of Band Tuner (VLP38++ only)
• Tuning Range : Air VHF - 2~13, UHF - 14~69
Analog Cable - 1~`25
Digital Cable - 1~135
•Antenna Input : 2 RF 75Ω unbalanced
LT-46244
VLP38+ Chassis
LT-46144
LT-52144

• TVGUIDEand otherrelated marks areregistered marks ofGemstar-TV
GuideInternational, Inc. and/or one of its affiliates.
• HDMI™is a trademark of HDMILicensing, LLC
• CableCARDisa trademark ofCableTelevisionLaboratories, Inc.
• Dolbyand Dolby digitalare registeredtrademarks of Dolby Laboratories.
• DTV Link is a trademark of Consumer ElectronicsAssociation

Page 3
MODELS: LT-40133 / LT-46133 / LT-52133 / LT-40134 / LT-46144 / LT-52144 / LT-46244 / LT-52244
INTRODUCTION ................................................................................................................................5
Dimensions,weight, powerusage, etc............................................................................................5
PRODUCTSAFETY NOTICE ............................................................................................................. 5
SAFETY PRECAUTIONS .................................................................................................................6
DISASSEMBLY ..................................................................................................................................7
BackCoverRemoval .......................................................................................................................7
LCDStandRemoval ........................................................................................................................8
RearInputCoverRemoval ............................................................................................................... 8
WallMounting Brackets Removal ...................................................................................................9
Chassis& Stand Holder Removal....................................................................................................9
CHASSISDISASSEMBLY
PWB-DMCoverRemoval .............................................................................................................. 10
PWBsPower, Signal & DMRemoval ............................................................................................ 10
LT-52122&LT-5244PWB-DMRemoval ......................................................................................... 11
PWB-DMEndPlate Removal........................................................................................................11
LCDPANEL REPLACEMENT
ASSY-SIDE-TERMINALRemoval .................................................................................................. 12
BezelRemoval .............................................................................................................................. 12
40”& 46” Screen Brackets Removal ............................................................................................. 13
52”ScreenBrackets Removal ....................................................................................................... 14
SETUP,INTIALIZATION & ERROR CODES
UserControls................................................................................................................................15
OptionMenu & Digital Signal Strength ..........................................................................................16
Reset & Initalization ...................................................................................................................... 17
InitalSettings................................................................................................................................ 18
LedIndication ...............................................................................................................................19
ErrorCodes .................................................................................................................................. 20
USINGLEAD FREE SOLDER .......................................................................................................... 21
CHIPPARTSREPLACEMENT ......................................................................................................... 22
REPLACEMENTPARTS .................................................................................................................. 23
PartsOrdering .............................................................................................................................. 23
Criticaland WarrantyParts Designation........................................................................................ 23
PartsTolerance Codes.................................................................................................................. 23
Quick Reference List...................................................................................................................... 24
SERVICE PARTS LIST .................................................................................................................... 25
CIRCUITRYBLOCK DIAGRAMS ..................................................................................................... 32
MainPower Supply ....................................................................................................................... 32
PWB-DM DC to DC Supplies ........................................................................................................33
OverallVideoSignal Path ............................................................................................................. 34
PWB-SIGNALVideo Select Circuitry ............................................................................................ 35
OverallAudioSignalPath.............................................................................................................. 36
PWB-TERMINALSound Select Circuitry ...................................................................................... 37
CONTENTS

MODELS: LT-40133 / LT-46133 / LT-52133 / LT-40134 / LT-46144 / LT-52144 / LT-46244 / LT-52244
Page 4
OverallControlCircuitry ................................................................................................................ 38
AutoInput/Output Detect Circuitry ................................................................................................ 39
Short Protect Circuitry .................................................................................................................. 40
SCHEMATICDIAGRAMS .....................................................................................................................
Digital Light Processing, Digital Micro Mirror Device and DLP are Trademarks of Texas Instruments.
Dolby and Dolby digital are registered trademarks of Dolby Laboratories.
DTV Link is a trademark of Consumer Electronics Association
HDMI, the HDMI logo and High-Definition Multimedia Interface are trademarks or registered trademarks of HDMI Licensing, LLC..

MODELS: LT-40133 / LT-46133 / LT-52133 / LT-40134 / LT-46144 / LT-52144 / LT-46244 / LT-52244
Page 5
INTRODUCTION
Thisservice manual provides service instructions for LCD Flat Panel TV Models and Chassis:
PRODUCT SAFETY NOTICE
Many electrical and mechanical parts in television receivers have special safety related characteristics. These charac-
teristics are often not evident from visual inspection nor can the protection afforded by them necessarily be obtained by
usingreplacement componentsrated for higher voltage, wattage, etc.
Replacementparts which have special safety characteristics are identified in this service manual.
Electrical components having such features are identified by shading on the schematic diagram and parts list of this
service manual, and by marking on the supplementary sheet for this chassis to be issued subsequently. Therefore,
the replacement for any safety part should be identical in value and characteristics.
Pb Solder
The PWBs used in the VLP38, VLP38+ and VLP38++ chassis are constructed using Lead-Free
solder. When servicing use only recommended Lead-Free solder (refer to page 21).
LT-46244
MODEL CHASSIS HEIGHT HEIGHT
w/o base WIDTH DEPTH DEPTH
w/o base WEIGHT w base POWER USAGE
LT-40133 VLP38 26" 23.9" 37" 12.6" 5.6" 68.7 lbs 250W
LT-46133 VLP38 29" 26.9" 42.3 " 12.6" 5.6" 85.9 lbs 300W
LT-52133 VLP38 32.4" 30.4" 48" 14.2" 5.7" 98 lbs 370W
LT-40134 VLP38M 26" 23.9" 37" 12.6" 5.6" 68.7 lbs 250W
LT-46144 VLP38+ 29" 26.9" 42.3 " 12.6" 5.6" 85.9 lbs 325W
LT-52144 VLP38+ 32.4" 30.4" 48" 14.2" 5.7" 98 lbs 395W
LT-46244 VLP38++ 29" 26.9" 42.3 " 12.6" 5.6" 85.9 lbs 325W
LT-52244 VLP38++ 32.4" 30.4" 48" 14.2" 5.7" 98 lbs 395W
Product Demensions & Weight

Page 6
MODELS: LT-40133 / LT-46133 / LT-52133 / LT-40134 / LT-46144 / LT-52144 / LT-46244 / LT-52244
Leakage current check
Before returning the receiver to the customer, it is recommended that leakage current be measured according to the
followingmethods.
1. Cold Check
With the alternating current (AC) plug removed from the AC source, place a jumper across the two AC plug
prongs. Connect one lead of an ohm meter to the AC plug and touch the other lead to each exposed metal part
(i.e. antennas, handle bracket, metal cabinet, screw heads, metal overlay, control shafts, etc.), particularly any
exposed metal part that has a return path to the chassis. The resistance of the exposed metal parts having a
return path to the chassis should be a minimum of 1Meg Ohm. Any resistance below this value indicates an
abnormalconditionand requires correctiveaction.
2. Hot Check ...Use the circuit shown below to perform the hot check test.
1. Keep switch S1 open and connect the receiver to the measuring circuit. Immediately after
connection, andwith the switching devices of the receiver in their operating positions,measure the
leakage current for both positions of switch S2.
2. Close switch S1, energizing the receiver. Immediately after closing switch S1, and with the
switchingdevices of the receiver in their operating positions, measure the leakage current forboth
positions of switch S2. Repeat the current measurements of items 1 and 2 after the receiver has
reached thermal stabilization. The leakage current must not exceed 0.5 milliampere (mA).
SAFETY PRECAUTIONS
NOTICE: Observeall cautions andsafety related noteslocated inside thereceiver cabinet and on the receiver
chassis.
WARNING:
1. Operationof this receiver outside the cabinet or with the coverremoved presents a shock hazard from the
receiver's power supplies. Work on the receiver should not be attempted by anyone who is not thoroughly
familiarwith the precautions necessary when working onhigh voltage equipment.
2. Donot install, remove or handle the LCD panel in any manner unlessshatterproof goggles areworn. People
not so equipped should be kept away while the panel is being handled. Keep the panel away from the body
whilehandling.
3. Whenservice is required, observethe original lead dress. Where a short-circuit has occurred, replace those
componentsthat indicate evidenceof overheating.
4. If the LCD Panel is damaged, crystalline liquid may leak from the LCD panel and broken glass may be
scattered. The crystalline liquid is toxic. Avoid contact with your skin, eyes, or mouth. DO NOT touch the
broken glass or crystalline liquid with bare hands, as cuts, poisoning, and/or skin irritation may occur. DO
NOT let glass fragments or crystalline liquid get into your eyes or mouth. Should either contact your eyes or
mouth, rinse the contacted area thoroughly with water and consult your doctor.
5. The fluorescent tubes in the panel contain mercury that is toxic and if broken should not be touched.
6. DO NOT dispose of the TV with general household waste. Follow local laws and regulations for legal and
safe disposal of theTV. For disposal or recycling information, contact local authorities or the Electronic
IndustriesAllianceat www.eiae.org.

MODELS: LT-40133 / LT-46133 / LT-52133 / LT-40134 / LT-46144 / LT-52144 / LT-46244 / LT-52244
Page 7
Back Cover Removal
Back Cover Removal Procedure
1) Remove24 screws(A) from the back cover
(21 screws on 40” models).
2) Pull the back cover from the TV.
Back Cover Installation
Reversetheremovalprocedure.
52” MODELS
40” & 46”
MODELS
LT-40133
LT-40134
LT-46133
LT-46144
LT-46244
LT-52133
LT-52144
LT-52244

Page 8
MODELS: LT-40133 / LT-46133 / LT-52133 / LT-40134 / LT-46144 / LT-52144 / LT-46244 / LT-52244
LCD Stand Removal
Stand Removal Procedure
1) Lay the unit face down on a soft non-scratching surface.
2) Remove4 screws (B)
3) Pull the stand from the bottom of the unit.
Rear Input’s Cover Removal
1) Remove4 screws (c)
2) Carefullypull offthe rear input’scover.

MODELS: LT-40133 / LT-46133 / LT-52133 / LT-40134 / LT-46144 / LT-52144 / LT-46244 / LT-52244
Page 9
Wall Mounting Brackets Removal
1) Remove8 screws(D) (4 on 52” models).
2) Lift the mounting brackets from the unit.
Chassis & Stand Holder Removal
Chassis Removal Procedure
1) Remove6 screws (A).
2) Remove two screws (B). (40 & 46 inch models only)
3) Unplug all inter-connecting cabels and lift the chassis from the unit.
Stand Holder Removal
1) Removescrews (c).
2) Lift the stand holder from the unit..

Page 10
MODELS: LT-40133 / LT-46133 / LT-52133 / LT-40134 / LT-46144 / LT-52144 / LT-46244 / LT-52244
PWB-DM Cover Removal
1) Removescrews (F) toremove theLVDS Cover.
2) Removescrews (E)to removethe DM-COVERand EARTHPLATE.
3) Liftthe PWB-DM Cover from the unit.
Chassis Disassembly
PWBs Power, Signal & DM Removal
1) PWB-POWERremove (10) screws (D).
2) PWB-SIGNALremove 6 screws (C).
3) PWB-DMremove 3 screwS (A) fromthe end bracket and service connector cover,
and screws (B) from the PWB-DM.
NOTE: Additionaldisassembly required inLT-52244(Seefollowing page)