Mitsubishi Electric Unisen LT-55154 User manual

Version 13.0 05/05/2011
MITSUBISHI DIGITAL ELECTRONICS AMERICA, INC.
9351 Jeronimo Road, Irvine, CA 92618-1904
Copyright © 2010 Mitsubishi Digital Electronics America, Inc.
All Rights Reserved
CAUTION:
Before servicing this chassis, it is important that the service person read the "SAFETY PRECAUTIONS" and
"PRODUCT SAFETY NOTICE" contained in this manual.
LCD FLAT PANEL HDTV
VLP43 Chassis
LT-55154
VLP43+ Chassis
LT-40164
LT-46164
LT-55164
SPECIFICATIONS
• Power Input : AC 120V, 60Hz
• LCD Panel : Resolution - 1920 x 1080
: Refresh Rate -
120 Hz (VLP43, VLP43+)
240 Hz (VLP43++)
• Tuning : NTSC/ATSC/QAM
: Analog Cable - 1~125
Digital Cable - 1~135
•Antenna Input : RF 75 Ohms unbalanced
• Speakers : 2W x 12 (VLP43)
: 2W x 16 (VLP43+)
: 2W x 16 & 20W x 2 (VLP43++)
• See Page 5 for additional specifications.
• Design specifications are subject to change without notice.
Manual
Service
VLP43++ Chassis
LT-46265
LT-55265
• Analog Input : VIDEO IN JACK (RCA Type)
Level Y/Video - 1.0Vp-p, Cr, Cb - 700mVp-p
75unbalanced
: AUDIO / CENTER CHANNEL IN JACK
(RCA Type)
-4.7dBm 43kunbalanced
• Analog Output : AUDIO / SUBWOOFER OUT JACK
Level (RCA Type)
-4.7dBm 4.7kunbalanced
• Digital : HDMI™ 1.3 Inputs
Inputs/Outputs : Digital Audio Output (RCA)(AC-3, PCM)
: USB Input
: Wired IR Input/Output (VLP43++)
: WiFi (VLP43+, VLP43++)
: Ethernet
: Bluetooth (VLP43+, VLP43++)
2010

Page 3
MODELS: LT-55154 / LT-40164 / LT-46164 / LT-55164 / LT-46265 / LT-55265
CONTENTS
INTRODUCTION..................................................................................................................................5
Dimensions, Weight, etc...................................................................................................................5
PRODUCT SAFETY NOTICE..............................................................................................................5
SAFETY PRECAUTIONS....................................................................................................................6
DISASSEMBLY & PARTS REPLACEMENT......................................................................................7
Back Cover Removal........................................................................................................................7
Panel Holder Removal......................................................................................................................7
Stand Removal.................................................................................................................................8
Major Component Locations.............................................................................................................9
LCD Panel Removal.........................................................................................................................9
Assembly–Speaker-Box Removal..................................................................................................10
Assembly–Speaker-Box Disassembly............................................................................................10
PWB-CONTROL Removal .............................................................................................................11
PWB-FILTER Removal...................................................................................................................11
PWB-POWER Removal .................................................................................................................12
WLAN-MODULE Removal .............................................................................................................12
PWB-MAIN (Assembly) Removal...................................................................................................12
PWB-MAIN Removal......................................................................................................................13
Wiring and Wire Clamp Locations..................................................................................................14
SERVICE PROCEDURES .................................................................................................................15
Remote Control ..............................................................................................................................15
Option Menu...................................................................................................................................16
Reset and Initialization ...................................................................................................................17
Backup / Restore ISF Settings .......................................................................................................18
Set Screen Size..............................................................................................................................19
LED Indications & Self Diagnostics................................................................................................20
Error Codes ....................................................................................................................................21
Sound Projector Transducer Test ..................................................................................................22
USING LEAD FREE SOLDER...........................................................................................................23
CHIP PARTS REPLACEMENT .........................................................................................................24
REPLACEMENT PARTS...................................................................................................................25
Parts Ordering ................................................................................................................................25
Critical and Warranty Parts Designation ........................................................................................25
Parts Tolerance Codes...................................................................................................................25
PARTS QUICK REFERENCE ...........................................................................................................26
SERVICE PARTS LIST......................................................................................................................27
CIRCUIT BLOCK DIAGRAMS ..........................................................................................................51
SCHEMATIC DIAGRAMS .................................................................................................................55

Page 4
MODELS: LT-55154 / LT-40164 / LT-46164 / LT-55164 / LT-46265 / LT-55265
HDMI, the HDMI logo and High-Definition Multimedia Interface are trademarks or registered trademarks of HDMI Licensing, LLC..

Page 5
MODELS: LT-55154 / LT-40164 / LT-46164 / LT-55164 / LT-46265 / LT-55265
INTRODUCTION
This service manual provides service instructions for the VLP43, VLP43+ and VLP43++ chassis types. The specific
models for each chassis type, dimensions and weight are listed below. Service personnel should read this manual
thoroughly before servicing these chassis.
This service manual includes:
1. Disassembly & parts replacement instructions.
2. Service Procedures.
3. Using lead free solder.
4. Chip parts replacement procedures.
5. Replacement part Instructions
6. Replacement parts list
7. Circuit block diagrams
8. Schematic diagrams
PRODUCT SAFETY NOTICE
Many electrical and mechanical parts in television receivers have special safety related characteristics. These char-
acteristics are often not evident from visual inspection nor can the protection afforded by them necessarily be ob-
tained by using replacement components rated for higher voltage, wattage, etc.
Replacement parts which have special safety characteristics are identified on the schematic diagrams and parts list
of this service manual. The replacement for any safety part should be identical in value and characteristics.
The PWBs used in this chassis are constructed using Lead-Free Solder. When servicing use
only recommended Lead-Free Solder. Refer to the section “Using Lead Free Solder.”
Dimensions, Weight & Power Consumption
MODEL CHASSIS HEIGHT
HEIGHT
w base WIDTH DEPTH
at panel Depth at speakers DEPTH w base WEIGHT w base POWER USAGE
NORMAL STANDBY
LT-40164 VLP43+ 26" 27.3" 38.1" 1.9" 2.9" 11.5" 45.5 lbs 230W 0.4W
LT-46164 VLP43+ 29.0" 30.2" 43.3" " 2.9” " 51.7 lbs 280W "
LT-46265 VLP43++ " " " " 3.0" " 53.9 lbs " "
LT-55154 VLP43 33.3" 34.6" 50.9 " 2.9" 12.9" 63.6 lbs 295W "
LT-55164 VLP43+ " " " " 2.9" " 63.6 lbs " "
LT-55265 VLP43++ " " " " 3.0" " 65.8 lbs " "

Page 6
MODELS: LT-55154 / LT-40164 / LT-46164 / LT-55164 / LT-46265 / LT-55265
GWG - Green Wire Ground
(Earth Ground)
S2
S1
OPEN
GROUND
SUPPLY CONNECTOR GROUND
RECEIVER
INSULATED TABLE
TOUCH ALL
EXPOSED
METAL PARTS
AC MA
METER
L
N
SAFETY PRECAUTIONS
NOTICE:
Observe all cautions and safety related notes located inside the receiver cabinet and on the receiver chassis.
WARNING:
1. Operation of this receiver outside the cabinet or with the cover removed presents a shock hazard from the
receiver's power supplies. Work on the receiver should not be attempted by anyone who is not thoroughly
familiar with the precautions necessary when working on high voltage equipment.
2. Do not install, remove or handle the LCD panel in any manner unless shatterproof goggles are worn. People
not so equipped should be kept away while the panel is being handled. Keep the panel away from the body
while handling.
3. When service is required, observe the original lead dress. Where a short-circuit has occurred, replace those
components that indicate evidence of overheating.
4. If the LCD Panel is damaged, crystalline liquid may leak from the LCD panel and broken glass may be scat-
tered. 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. DO NOT dispose of the TV with general household waste. Follow local laws and regulations for legal and
safe disposal of the TV. For disposal or recycling information, contact local authorities or the Electronic Indus-
tries Alliance at www.eiae.org.
Leakage current check
Before returning the receiver to the customer, it is recommended that leakage current be measured according to the
following methods.
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
abnormal condition and requires corrective action.
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, and
with 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 switching devices
of the receiver in their operating positions, measure the leakage current for both positions of switch S2. Re-
peat the current measurements of items 1 and 2 after the receiver has reached thermal stabilization. The
leakage current must not exceed 0.5 milliamps (mA).

Page 7
MODELS: LT-55154 / LT-40164 / LT-46164 / LT-55164 / LT-46265 / LT-55265
DISASSEMBLY & PARTS REPLACEMENT
Back Cover Removal
NOTE: It is not necessary to remove the Stand for Back Cover removal.
1. Remove screws (A).
2. Lift the back cover from the TV.
A
A
A
A
HOLDER-PANEL Removal (for Panel or Front Bezel replacement)
1. Release HOLDER-PANEL from top center of TV.
NOTE: In case HOLDER-PANEL accidentally comes loose after Back Cover removal, be certain to re-install it
before reassembly.
HOLDER-PANEL
NOTE: Unless noted, instructions are for all models.
Illustrations may differ slightly depending upon the actual model being serviced.

Page 8
MODELS: LT-55154 / LT-40164 / LT-46164 / LT-55164 / LT-46265 / LT-55265
Stand Removal
NOTE: The Stand can be removed either before or after Back Cover removal.
1. Remove screws (B) and for 55” models (C) and lift TV off stand.
2. Place TV face down on a clean soft surface.
C
B
B
B B
C
Stand Removal with Back Cover on..
Stand Removal with Back Cover off.
(55” Models Only)
(55” Models Only)

Page 9
MODELS: LT-55154 / LT-40164 / LT-46164 / LT-55164 / LT-46265 / LT-55265
LCD Panel Replacement
NOTE: Do not remove the T-CON and LED-POWER PWBs. Replacement Panels Include these items.
1. Remove the Back Cover and Stand.
2. Remove all Major Components and assemblies along with the associated hardware and wiring.
3. Reverse the procedure to install a replacement.
Major Component Locations
PWB-MAIN
STAY-VESA-T
PWB-POWER
PWB-FILTER WLAN-MODULE
(VLP43+ &VLP43++)
PWB-LED
(VLP43 & VLP43+)
PWB-PREAMP2
(V43++)
T-CON
(Non-Replaceable)
ASSEMBLY-
SPEAKER-BOX BLUETOOTH
MODULE
(VLP43+ & VLP43++)
PWB-
CONTROL
BRACKET-BOTTOM
(Assembly) LED-POWER
(Non-Replaceable)
HOLDER-
PANEL

Page 10
MODELS: LT-55154 / LT-40164 / LT-46164 / LT-55164 / LT-46265 / LT-55265
ASSEMBLY-SPEAKER-BOX Removal
1. Remove screws (A).
A
ASSEMBLY-SPEAKER-BOX Disassembly
1. Remove the screws indicated on the Speaker Box by the arrows.
2. Separate the back from the front cabinet.
BEZEL Removal
1. VLP43++ Disconnect the SB connector
from the PWB-MAIN and release the wiring
harness from the taped locations leading to
the PWB-SBL.
2. Release the clips around the Bezel and
remove from the front.
3. VLP43++ Carefully feed the SBL wiring
harness from the back as the Bezel is be-
ing removed.
Note: Upon re-assembly be certain the wiring is
routed so it will not get caught in the chan-
nel of the Stand Mounting Bracket.
PWB-SBL Removal (VLP43++)
1. Remove the Bezel as described above.
Note: Use caution when removing the tape from
the wiring connector on the PWB-SBL. SB
PWB-SBL