Text preview for : LC-32FC18.pdf part of . Various LC-32FC18 . Various CHINA TV LCD LC-32FC18.pdf
Back to : LC-32FC18.pdf | Home
LCD TELEVISION
LC-32FC18
America
CONTENTS
Safety precautions...................................................................................... 1
Alignment instructions ................................................................................ 3
Working principle analysis of the unit...............................................................8
Block diagram .............................................................................................9
IC block diagram.........................................................................................10
Wiring diagram ........................................................................................ 16
Troubleshooting......................................................................................... 17
Schematic diagram.................................................................................... 27
APPENDIX-A: Assembly list
APPENDIX-B: Exploded View
Attention: This service manual is only for service personnel to take reference with. Before
servicing please read the following points carefully.
Safety precautions
1. Instructions
Be sure to switch off the power supply before replacing or welding any components or
inserting/plugging in connection wire Anti static measures to be taken (throughout the entire
production process!):
a) Do not touch here and there by hand at will;
b) Be sure to use anti static electric iron;
c) It's a must for the welder to wear anti static gloves.
Please refer to the detailed list before replacing components that have special safety requirements.
Do not change the specs and type at will.
2. Points for attention in servicing of LCD
2.1 Screens are different from one model to another and therefore not interchangeable. Be sure to
use the screen of the original model for replacement.
2.2 The operation voltage of LCD screen is 700-825V. Be sure to take proper measures in
protecting yourself and the machine when testing the system in the course of normal operation or
right after the power is switched off. Please do not touch the circuit or the metal part of the module
that is in operation mode. Relevant operation is possible only one minute after the power is
switched off.
2.3 Do not use any adapter that is not identical with the TV set. Otherwise it will cause fire or
damage to the set.
2.4 Never operate the set or do any installation work in bad environment such as wet bathroom,
laundry, kitchen, or nearby fire source, heating equipment and devices or exposure to sunlight etc.
Otherwise bad effect will result.
2.5 If any foreign substance such as water, liquid, metal slices or other matters happens to fall into
the module, be sure to cut the power off immediately and do not move anything on the module lest it
should cause fire or electric shock due to contact with the high voltage or short circuit.
2.6 Should there be smoke, abnormal smell or sound from the module, please shut the power off at
once. Likewise, if the screen is not working after the power is on or in the course of operation, the
power must be cut off immediately and no more operation is allowed under the same condition.
2.7 Do not pull out or plug in the connection wire when the module is in operation or just after the
power is off because in this case relatively high voltage still remains in the capacitor of the driving
circuit. Please wait at least one minute before the pulling out or plugging in the connection wire.
2.8 When operating or installing LCD please don't subject the LCD components to bending, twisting
or extrusion, collision lest mishap should result.
2.9 As most of the circuitry in LCD TV set is composed of CMOS integrated circuits, it's necessary
to pay attention to anti statics. Before servicing LCD TV make sure to take anti static measure and
ensure full grounding for all the parts that have to be grounded.
2.10 There are lots of connection wires between parts behind the LCD screen. When servicing or
moving the set please take care not to touch or scratch them. Once they are damaged the screen
1
would be unable to work and no way to get it repaired.
If the connection wires, connectors or components fixed by the thermotropic glue need to disengage
when service, please soak the thermotropic glue into the alcohol and then pull them out in case of
dagame.
2.11 Special care must be taken in transporting or handling it. Exquisite shock vibration may lead to
breakage of screen glass or damage to driving circuit. Therefore it must be packed in a strong case
before the transportation or handling.
2.12 For the storage make sure to put it in a place where the environment can be controlled so as to
prevent the temperature and humidity from exceeding the limits as specified in the manual. For
prolonged storage, it is necessary to house it in an anti-moisture bag and put them altogether in one
place. The ambient conditions are tabulated as follows:
Temperature Scope for operation 0 ~ +50 oC
Scope for storage -20 ~ +60 oC
Humidity Scope for operation 20% ~ 85%
Scope for storage 10% ~ 90%
2.13 Display of a fixed picture for a long time may result in appearance of picture residue on the
screen, as commonly called "ghost shadow". The extent of the residual picture varies with the
maker of LCD screen. This phenomenon doesn't represent failure. This "ghost shadow" may remain
in the picture for a period of time (several minutes). But when operating it please avoid displaying
still picture in high brightness for a long time.
3. Points for attention during installation
3.1 The front panel of LCD screen is of glass. When installing it please make sure to put it in place.
3.2 For service or installation it's necessary to use specified screw lest it should damage the screen.
3.3 Be sure to take anti dust measures. Any foreign substance that happens to fall down between
the screen and the glass will affect the receiving and viewing effect
3.4 When dismantling or mounting the protective partition plate that is used for anti vibration and
insulation please take care to keep it in intactness so as to avoid hidden trouble.
3.5 Be sure to protect the cabinet from damage or scratch during service, dismantling or mounting.
2
Alignment instructions
1. Test equipment
Digital Multi-meter
54200 (Signal generator)
PC (FLASH writing programs have to be installed first, W24CXX.EXE)
VG849 (HDMI signal generator)
CA210 (White balancer)
DVD player (with HDMI output)
Monitor
2. The alignment flow chart (see below figure)
FLASH write N501, N142, N710, N801
Production of main board, high frequency board,
other little board power board on the line
Analog board power test
Check accessories and then packing
Digital board power test
Input VGA signal, check if display is normal in
the state of PC and various functions (analog
Test of Button board and IR board control), line/ field center etc.
Combined test for general assembly Input HDMI and HDTV signal (use a connection
wire, input audio signal from D-sub Audio in),
check if HDCP KEY, picture and sound are
normal
Aging
Input YPbPr/YcbCr 1/2 signal and check if
ADC emendation and white balance adjustment picture, sound and analog quantity control is
normal in the state of COMPONENT.
Connect to central signal source, check
various TV functions (station search, system Input AV1/S/AV2 signal, check various functions
identify, modulate quantity control etc), check if under each terminal (system identify, analog
the output of earphone and speaker are normal control etc), check if Picture and sound of AV-out
Picture and sound of AV-out is normal. (check is normal. (S-terminal and AV1 share the same
stereo/SAP and CCD, VCHIP for America) . audio channel, the output picture from AV-out is
colorless in the status of S-terminal)
Fig.1 Flow process of alignment
3
3. Flash writing programs
Connect the digital board, analog board, trans-connect board and power board according the wiring
diagram.
Flash write N710, N711
a) Flash write W24CXX.EXE to N710, N711 with self-made flash write tool on the line.
b) Upgrade software from USB interface.
Note: N710, N711 may upgrade from HDMI and VGA interface respectively. a) and b) can be done
at the same time.
4. Unit adjustment
Connect the digital board, analog board, trans-connect board, button board, IR board and power
board according the wiring diagram. Put the power on and observe if the display is normal.
4.1 Adjustment of Digital board and Analog board
a) Press POWER button on the remote control, the indicator light on IR receive board turns blue.
b) Press the buttons "INPUT, 2, 5, 8, 0" one by one to enter factory menu, select "Result" item, and
check if each item in this page is "", otherwise, the IC mentioned in the item is failure.
c) Check if picture and sound are normal of all the channels, if STEREO/SAP can be identified
correctly. Check AV-OUT function: the picture and sound of AV-OUT should be the picture and
sound of the current channel at TV/AV1/S/AV2, AV-OUT of other signal source don't need to
check.
4.2 Adjustment of unit connection
Turn on the TV and check if it is normal: display LOGO about 2 seconds later, display picture about
10 seconds later.
4.3 Aging
a) Turn on the TV, select TV channel without signal input.
b) Aging for an hour in the aging room.
4.4 White balance adjustment of ACD (use CA210, VG849 generator)
Enter MENU Picture Picture Settings, set "Preset" to standard.
Note:
1) Press "" and "" to switch factory menu item, and "ENTER" to access, press"" and "" to
select adjustment item, press"" and ""or input digital data to adjust value of the item,
press "EXIT" to exit.
2) Coordinate of cold color temperature 12000K is (X=270, Y=283), coordinate of warm color
temperature 7500K is (X=300, Y=306), coordinate of normal color temperature 9300K is (X=285,
Y=293).
4.4.1 Adjustment of YPBPR, VGA, ADC
a) Press" INPUT, 2.5.8.0"one by one to enter factory menu.
b) Press"" to move cursor to "Adc Calibrate" item, press" ENTER" to access.
c) Input YPrPb signal (VG-848, Timing 978(483P), Pattern 984 SMPTE Color Bar), move
cursor to START and press "ENTER" to auto adjust until complete
d) Input YPRPB signal (VG-848, Timing 976(720P), Pattern 984 SMPTE Color Bar), move
cursor to START and press "ENTER" to auto adjust until complete
e) Move cursor to Source, press "ENTER" switch to Anolog RGB(VGA). Input VGA signal
(VG-848 Timing 856(1024*768/60HZ), Pattern 920 Gray 8 step(H)), move cursor to START
and press "ENTER" to auto adjust until complete
4
4.4.2 Adjustment of white balance
Input HDMI signal and check the white balance at HDMI channel.
a) Enter "color temperature setting" menu, select "color temperature" of "NORMAL".
b) Input 16-level gray signal of the mode 1024*768 @60HZ (TIMING:856, PATTERN:921).
c) Fix BLUE GAIN at 1000, adjust RED GAIN, BLUE GAIN to set the color coordinates of
fourteenth level to (X=285, Y=293).
d) Set the color coordinates of warm color temperature (WARM) to (X=300, Y=306) using the
same method.
e) Set the color coordinates of cool color temperature (COOL) to (X=270, Y=283) using the same
method.
f) Check if the color coordinates of the cool/warm color temperature at YPBPR (include
480P,720P), VIDEO(NTSC) and TV channels are within the scope of the correspond value
(permit