Toshiba 32WL46B User manual

SERVICE MANUAL
LCD Colour TV
32WL46B
32WL46G
F4LW Chassis
FILE NO. 070-200405
May. 2004 (YC/X)

PC BOARDS BOTTOM VIEW............................................................................................................................................ 67
SPECIFICATIONS .......................................................................................................................................................... END
APPENDIX:
SCHEMATIC DIAGRAM
TABLE OF CONTENTS
SERVICE SAFETY PRECAUTIONS ................................................................................................................................... 3
HANDLING
SERVICE MODE
THE LCD MODULE .........................................................................................................................................
.................................................................................................................................................................
5
7
LOCATION OF CONTROLS............................................................................................................................................... 11
LAYOUT OF MAJOR BOARDS........................................................................................................................................... 15
MECHANICAL DISASSEMBLY.......................................................................................................................................... 16
EXPLODED VIEW ............................................................................................................................................................. 35
PACKING DISASSEMBLY................................................................................................................................................. 39
CHASSIS AND CABINET REPLACEMENT PARTS LIST ................................................................................................. 41
PC BOARDS TOP & BOTTOM VIEWS ............................................................................................................................ 53
CIRCUIT BLOCK DIAGRAM
WIRING CONNECTIONS .................................................................................................................................................. 29
– 2–

GENERAL ADJUSTMENTS
SPECIFIC INFORMATIONS
SERVICE SAFETY PRECAUTIONS
• The caution items shown here describe major safety issues and should always be observed.
• The meanings of the various indications are as follows.
WARNING
CAUTION
Indicates a hypothetical situation in which service personnel and nearby third parties, or even
end users due to a product defect after the service operation is completed, could possibly be in
danger of injury or even death in the event of operational error.
Indicates a hypothetical situation in which service personnel and nearby third parties, or even
end users after the service operation is completed, could possibly be in danger of injury, or
where there could be physical damage in the event of operational error.
* Physical damage means major damage to a home, furnishings and other possessions.
Examples of marks
SHOCK HAZARD
PROHIBIT DISASSEM-
BLING
UNPLUG
The " indicates caution (including danger and warning).
The actual meaning of this caution is indicated inside the
" or nearby illustrations or text.
The example shown to the left indicates the danger of "electrical shock".
The indicates a forbidden action.
The actual meaning of this caution is indicated inside the or nearby illustrations or text.
The example shown to the left indicates that disassembly is forbidden.
The -indicates a forced action (an action that must be performed).
The actual meaning of this forced action is indicated by -or nearby illustrations or text.
The example shown to the left indicates that the power plug must be disconnected.
–3 –

GENERAL ADJUSTMENTS
SPECIFIC INFORMATIONS
WARNING
KEEP CHILDREN
AWAY
UNPULUG
SHOCK HAZARD
USE SPECIFIED
PARTS
CAUTION FOR
WIRING
CAUTION FOR
ASSEMBLING /
WIRING
CHECK INSULATION
RESISTANCE
PROHIBIT
REMODELING
• Always advise users to keep children away.
There is danger of injury to children from tools, disassembled products, etc.
• Always disconnect the power plug before starting work whenever power is not required.
Failure to disconnect the power plug before starting work can result in electrical shock.
• Depending on the model, use an insulation transformer or wear gloves when servicing with the
power on, and disconnect the power plug to avoid electrical shock when replacing parts.
In some cases, alternating current is also impressed in the chassis, so electrical shock is pos-
sible if the chassis is contacted with the power on.
• Always use the replacement parts specified for the particular model when making repairs.
The parts used in products have the necessary safety characteristics such as inflammability,
voltage resistance, etc.; therefore, use only replacement parts that have these same character-
istics.
Use only the specified parts when the mark is included in a circuit diagram or parts list.
• Parts mounting and routing of the wiring should be the same as that used originally.
For safety purposes, insulating materials such as tubing or tape is sometimes used and printed
circuit boards are sometimes mounted floating.
Also make sure that wiring is routed and clamped to avoid parts that generate heat and which
use high voltage. Always follow the original scheme.
• After a repair has been completed, reassemble all disassembled parts, and route and recon-
nect the wiring, in accordance with the original scheme.
Do not allow internal wiring to be pinched by cabinets, panels, etc.
Any error in reassembly or wiring can result in electrical leakage, flame, etc., and may be
hazardous.
• After completing the work, disconnect the power plug from the outlet, remove the antenna, turn
on the power switch. Then, use a 500V insulation resistance meter to check the insulation
resistance of the antenna terminal, other metallic parts and between the prongs of the power
plug to make sure that the insulation resistance is 1M 1or more.
The set will require inspection and repair if the insulation resistance is below this value.
• Never remodel the product in any way.
Remodeling can result in improper operation, malfunction, or electrical leakage and flame,
which may be hazardous
–4 –

GENERAL ADJUSTMENTS
SPECIFIC INFORMATIONS
HANDLING THE LCD MODULE
Safety Precautions
In the event that the screen is damaged or the liquid crystal
(fluid) leaks, do not breathe in or drink this fluid. Also, never
touch this fluid.
Such actions could cause toxicity or skin irritation. If this fluid
should enter the mouth, rinse the mouth thoroughly with wa-
ter. If the fluid should contact the skin or clothing, wipe off
with alcohol, etc., and rinse thoroughly with water. If the fluid
should enter the eyes, immediately rinse the eyes thoroughly
with running water.
Precautions for Handling the LCD Module
The LCD module can easily be damaged during disassembly
or reassembly; therefore, always observe the following pre-
cautions when handling the module.
1. When attaching the LCD module to the LCD cover, posi-
tion it appropriately and fasten at the position where the
display can be viewed most conveniently.
2. Carefully align the holes at all four corners of the LCD
module with the corresponding holes in the LCD cover
and fasten with screws. Do not strongly push on the mod-
ule because any impact can adversely affect the perform-
ance. Also use caution when handling the polarized screen
because it can easily be damaged.
CAUTION
The metal edges of the LCD module
are sharp, so use caution to avoid in-
jury.
3. If the panel surface becomes soiled, wipe with cotton or a
soft cloth. If this does not remove the soiling, breathe on
the surface and then wipe again.
If the panel surface is extremely solied, use a CRT cleaner
as a cleaner. Wipe off the panel surface by drop the cleaner
on the cloth. Do not drop the cleaner on the panel. Pay
attention not to scratch the panel surface.
4. Leaving water or other fluids on the panel screen for an
extended period of time can result in discoloration or
stripes. Immediately remove any type of fluid from the
screen.
5. Glass is used in the panel, so do not drop or strike with
hard objects. Such actions can damage the panel.
6. CMOS-LSI circuitry is used in the LCD module, so avoid
damage due to static electricity. When handling the mod-
ule, use a wrist ground or anchor ground.
–5 –

GENERAL ADJUSTMENTS
F
IC INFORMATIONS
7. Do not expose the LCD module to direct sunlight or strong
ultraviolet rays for an extended period of time.
8. Do not store the LCD module below the temperature con-
ditions described in the specifications. Failure to do so
could result in freezing of the liquid crystal due to cold air
or loss of resilience or other damage.
9. Do not disassemble the LCD module. Such actions could
result in improper operation.
10. When transporting the LCD module, do not use packing
containing epoxy resin (amine) or silicon resin (alcohol or
oxim). The gas generated by these materials can cause
loss of polarity.
Cleaning
Remove the power plug before cleaning.
Do not use solvents such as benzine or thinner to clean the TV.
– These solvents may distort the cabinet or damage its finish.
– If rubber or vinyl products remain in contact with the TV for a long time, a stain may result.
When the cabinet becomes dirty, clean it with a soft, dry cloth.
When the cabinet is very dirty.
– Use a damp cloth to wipe the cabinet clean.
– Finish with a dry cloth.
When cleaning the surface of the LCD display:
– Wipe the panel surface gently with a soft, dry cloth.
When dust has collected on the power plug connectors, remove the plug from the outlet and clean off the
dust.
This dust may cause a fire due to reduced insulation on the plug.
–6 –

1. ENTERING TO SERVICE MODE
(1) Procedures
1)Press MUTE key of remote hand unit to indicate MUTE
on screen.
2) Press again MUTE key of remote hand unit to keep
pressing until the next procedure.
(OSD display disappears.)
3)In the status of above (2), press MENU key on TV set.
(2)During service mode, indication S is displayed at upper right
corner on screen.
(3) Service mode is not memorized as the last-memory.
2. TEST SIGNAL SELECTION
The function of VIDEO test signal selection is cyclically
changed with VIDEO key (remote unit) in Service mode.
3. SERVICE ADJUSTMENT
(1) ADJUSTMENT MENU INDICATION ON/OFF :
MENU key(on TV set)
(2) During display of adjustment menu,the followings are
effective.
1) Selection of adjustment item :
POS UP/DN key (on TV/Remote unit)
2) Adjustment of each item :
VOL UP/DN key (on TV/Remote unit)
3) Direct selection of adjustment item
R CUTOFF : 1 POS (Remote unit)
G CUTOFF : 2 POS (Remote unit)
B CUTOFF : 3 POS (Remote unit)
4) Data setting for PC unit adjustment
SUB CONTRAST : 4 POS (Remote unit)
SUB COLOR : 5 POS (Remote unit)
SUB TINT : 6 POS (Remote unit)
5)Screen adjustment mode ON/OFF: Previous
6) Test signal selection: VIDEO (Remote unit)
* In service mode, serviceable items are limited.
(3) Self check display : 9 POS (Remote unit)
* Cyclic display
(4) Initialization of memory (QA02 E2PROM) :
CALL (Remote unit)+POS UP(TV)
Causion : All data of memory IC (including factory setting
value) is initialized by this operation.
(Replacement of memory IC is required.)
(5) Initialization of self check data :
CALL (Remote unit)+POS DN(TV)
(6) BUS OFF :
CALL (Remote unit)+VOL UP(TV)
Test signal
No.
0
1
2
3
4
5
6
7
8
9
10
0
Name of pattern
Signal OFF
NTSC All Red signal
NTSC All Green signal
NTSC All Blue signal
NTSC Cross hatch
NTSC All white signal
PAL All Red signal
PAL All Green signal
PAL All Blue signal
PAL Cross hatch
PAL All white signal
Signal OFF
Table 1
SERVICE MODE
–7 –

TROUBLESHOOTING DIAGNOSIS FUNCTION
DIAGNOSIS FUNCTION FOR LED INDICATION
High : Lighting Low : No Lighting
CAUSE
Short-circuit detection of BUS line
BUS line may possibly be short-circuit (SDA to SCL), or BUS line (SDA, SCL)
is grounded.
Overcurrent limiter detection
POWER terminal on TV microprocessor becomes LOW at 2 seconds or more.
Interruption of FAN motor function detection
No. 53 terminal on TV microprocessor becomes HIGH for 30 seconds.
Abnormal sound detection
P4 terminal of QS10 becomes LOW for 15 seconds during Speaker is acti-
vated.
LED
LED is lit in 1 second at in-
tervals of 1 second.
LED is lit in 0.5 at intervals
of 0.5 second.
LED is lit in 0.25 second at
intervals of 2 second.
LED is lit in 5 seconds at in-
tervals of 5 seconds.
4. FAILURE DIAGNOSIS PROCEDURE
This model is equipped with self diagnosis function inside for trouble shooting.
4-1.Contents to be Confirmed by Customer
Contents of self diagnosis
Set Power does not turn on by power-key,or it turns off
automatically.
1.When power protection circuit operates;
2.When FAN STOP was detected:
3.When failure of Audio circuit was detected:
Display items and actual operation
Power indicator lamp blinks and picture does not come.
1.Power indicator red lamp blinks. (0.5 seconds interval)
2.Power indicator red lamp blinks. (3 seconds interval)
3.Power indicator red lamp blinks. (5 seconds interval)
If these indications appear, repairing work is required.
Table 2
–8 –

4-2. Contents to be Confirmed in Service Work (Check in Self Diagnosis Mode)
4-3. Executing Self Diagnosis Function
Procedures
(1) Set to service mode.
(2) Pressing “9” key on remote unit displays self diagnosis result on screen.
Every pressing changes mode as below.
SERVICE mode SELF DIAGNOSIS mode M2 System version info Version check(QA01,QM24 etc)
(3) To exit from service mode, turn power off.
Contents of self diagnosis
Contents of self diagnosis
B. Indication of part code of microprocessor.(QA01)
C. Total Time of Power on (hour)
D. Number of operation of power protection circuit
E. Check of communication status in BUS line
F.Check of signal line by sync signal detection
Display items and actual operation
Display items and actual operation
* Please see item.4-4
Table 3
<SELF DIAGNOSIS mode>
<OSD/TEXT M2 Sub System Information> <Version Check>
Description for Version Check Screen
QA01 ****
- Version information for MainMicom(QA01)
QA02 **
- Version information for E2PROM(QA02)
QF14 ****-**
- Version information for M2 Sub-Micom(QF14)
QM24 **
- Version information for BEP Sub-Micom(QM24)
QM17 **
- Version information for BEP E2PROM(QM17)
–9 –

4-4. Self Diagnosis Function Indication & Contents
SELF CHECK
23000XXX B
TIME C
POWER : 000 D
BusCont : OK E
Block : UV V1 V2 V3 V4 F
PC
<Example of screen display>
Fig. 1
Item
B) Partcode
C) TIME
D) POWER
E) BUS CONT
F) BLOCK
Contents
Indication of part code of microprocessor.
(QA01)
Total Time of Power on (hour)
Number of operation of power protection circuit
Communication state of bus line
The sync signal part in each video signal supplied
from each block is detected.
Then by checking the existence or non of sync part, the
result of self diagnosis is displayed on screen.
Besides, when “9” key on remote unit is pressed,
diagnosis operation is first executed once.
Instruction of results
Indication of“OK”for normal result
Indication of failure place in abnormality
(Failure place to be indicated)
QA02 NG, H001 NG, Q501 NG,
QV01 NG, Q4420 NG
H002 NG
QA02 : E2PROM, H001 : MAIN TUNER,
Q501 : MCD QV01: AVSW,
Q4420 : SCAN PROCESSOR
H002 : ITT,DSP,APRO
Note 1. The indication of failure place is only one
place though failure places are plural. When
repair of a failure place finishes, the next
failure place is indicated.
*Indication by color
Select Source
: Sync exists = Green
: No Sync = Red
Other Source
: Black
Table 4
– 10 –

LOCATION OF CONTROLS
Front
Remote sensor
Power switch
Power indicator
(red)
TV front view
On-timer
indicator
(green)
– 11 –

Back
Aerial input
EXT4 IN/OUT
(Scart 4)
RGB/PC IN
WOOFER OUT
EXT5 IN/OUT
(Scart 5)
EXT3 IN
(S-video/Video/
Audio input)
EXT1 IN
(Component video/
Composite video/Audio
input)
EXT2 IN
(Component
video/Composite
video/Audio
input)
MONITOR OUT [40]
(Audio/Video output)
AUDIO OUT
(Fixed/Variable)
Audio input
EXT3 IN/OUT
(Scart 3)
Back view
TV back view
Cable holder
Back view
Headphones jack
(3.5 mm, stereo)
EXT6 IN
(S-video/
Video/Audio
input)
Cable
holder
Back view Side view
– 12 –

Remote Control
DVD
MENU
P
P
2
13
5
4
6
8
79
VCR
TV
DVD
0
OK
CALL
MENU EXIT
CALL
Initial/index function for Teletext
Teletext on/off
To return to the previous programme
Picture mode selection
MENU
DVD MENU
• Menu
• Volume – +
OK
Stereo/bilingual selection
Mode switch
TV : To control TV
VCR : To control VCR
DVD : To control DVD
Power on/Standby
(For Toshiba TV/VCR/DVD)
Number buttons (0-9)
• Input source selection
(EXT1 - EXT6, RGB/PC)
• To access sub-pages when in
Teletext
Picture size selection
EXIT
• Menu
• Programme position
• Teletext
Teletext control buttons
(Four coloured buttons : Red,
Green, Yellow, Blue)
Bass boost on/off
External woofer on/off
Sound mute
When in VCR or DVD mode:
(Only for Toshiba VCR/DVD
players)
to PAUSE
to EJECT
to SKIP-REWIND
to SKIP-FORWARD
to PLAY
to STOP
to REWIND
to FAST FORWARD
When in TV (Teletext) mode:
To reveal concealed text
To hold a wanted page
To enlarge teletext display size
/To select a page whilst
viewing a normal picture
– 13 –

– 14 –
MEMO

– 15 –
LAYOUT OF MAJOR BOARDS
U800 POWER MODULE UNIT
U003 SCALER Board
U001B FRONT/AV Board
U002A TN/AOUT Board
U001C AV2 Board
U001G D-REWRITE Board
U001E KEY SW Board
U001F LED/RMT Board
U001D POWER SW Board
U001A SIGNAL Board
U002B PC INPUT Board

–16 –
MECHANICAL DISASSEMBLY
PP 5x12
Stand
BC Stand cover
BC Terminal cover
1. Removing the back cover
1) Remove the BC stand cover.
2) Remove the BC terminal cover.
3) Remove 6 screws, then remove the stand.
• Note: Be sure to lay down the main body (by placing its screen
downward) for disassembly.

–17 –
PBI 4x12
Back cover
PP 3x6
PP 3x6
PP 3x6
4) Remove 11 screws (PBI 4x12).
5) Remove 5 screws (PP 3x6).
6) Remove the back cover.

–18 –
2. Removing the speakers
1) Remove the back cover. (Refer to Item 1.)
2) Disconnect the speaker wire harness on the Front/AV board.
3) Remove the wire harness of the 3 wire holders.
4) Remove 4 screws, then remove the left speaker and wire holder.
5) Remove 4 screws, then remove the right speaker and wire holder.
PBI 4x12
Speaker (R)
Speaker
wire harness
Wire harness
Wire holder
Wire holder
Wire holde
r
Speaker (L)
PBI 4x12
FRONT/AV Board

–19 –
3. Removing the top shield bracket
1) Remove the back cover. (Refer to Item 1.)
2) Remove 5 screws, then remove the top shield bracket.
Top shield bracket
STP 3x8 STP 3x8

–20 –
4. Removing the Power Module unit
1) Remove the back cover. (Refer to Item 1.)
2) Disconnect the power cord from the connector.
3) Remove the 3 wire harnesses from the 3 wire clampers on the plate back R.
4) Disconnect the 8 wire harnesses from the 8 connectors on the Power Module unit.
5) Remove 7 screws, then remove the Power Module unit.
Power cord
STP 3x8
Wire harnesses Wire harnesses
Wire clampers
POWER MODULE UNIT
Plate back R