CHANGHONG 21NF55-21PF93 CRT TV – HOW TO ADJUST THE CONVERGENCE, SETUP ADJUSTMENTS, CIRCUIT DIAGRAM (SCHEMATIC)

Changhong 21NF55-21PF93 CRT TV – How to adjust the convergence, setup adjustments, circuit diagram (schematic)

SET-UP ADJUSTMENTS
The following adjustments should be made when a complete realignment is required or a new picture tube is installed.
Perform the adjustments in the following order:
1. Color purity
2. Convergence
3. White balance
The purity/convergence magnet assembly and rubber wedges need mechanical positioning.
For some picture tubes, purity/ convergence adjustments are not required.
Color Purity Adjustment
Preparation:
Before starting this adjustment, adjust the vertical sync, horizontal sync, vertical amplitude and focus.
1 Face the TV set north or south.
2 Connect the power plug into the wall outlet and turn on the main power switch of the TV set.
3 Operate the TV for at least 15 minutes.
4 Degauss the TV set using a specific degaussing coil.
5 Set the brightness and contrast to maximum.
6 Counter clockwise rotate the R/B low brightness potentiometers to the end and rotate the green low brightness potentiometer to center.
7 Receive green raster pattern signals.
8 Loosen the clamp screw holding the deflection yoke assembly and slide it forward or backward to display a vertical green zone on the screen. Rotate and spread the tabs of the purity magnet around the neck of the CRT until the green zone is located vertically at the center of the screen.
9 Slowly move the deflection yoke assembly forward or backward until a uniform green screen is obtained.
10Tighten the clamp screw of the assembly temporarily. Check purity o f the red raster and blue raster until purities of the three rasters meet the requirement.
Convergence Adjustment
Preparation:
Before attempting any convergence adjustment, the TV should be operated for at least 15 minutes.
1 Center convergence adjustment
1.1 Receive dot pattern.
1.2 Adjust the brightness/contrast controls to obtain a sharp picture.
1.3 Adjust two tabs of the 4-pole magnet to change the angle between them and red and blue vertical lines are superimposed each other on the center of the screen.
1.4 Turn both tabs at the same time keeping the angle constant to superimpose red and blue horizontal on the center of the screen.
1.5 Adjust two tabs of the 6-pole magnet to superimpose red/blue line and green line.
1.6 Remember red and blue movement. Repeat steps2.1.3-2..1.5 until optimal convergence is obtained.
2 Circumference convergence adjustment
2.1 Loosen the clamp screw holding the deflection yoke assembly and allow it tilting.
2.2 Temporarily put the first wedge between the picture tube and deflection yoke assembly. Move front of the deflection yoke up or down to obtain better convergence in circumference. Push the mounted wedge in to fix the yoke temporarily.
2.3 Put the second wedge into bottom.
2.4 Move front of the deflection yoke to the left or right to obtain better convergence in circumference.
2.5 Fix the deflection yoke position and put the third wedge in either upper space. Fasten the deflection yoke assembly on the picture tube.
2.6 Detach the temporarily mounted wedge and put it in either upper space. Fasten the deflection yoke assembly on the picture tube.
2.7 After fastening the three wedges, recheck overall convergence and ensure to get optimal convergence. Tighten the lamp screw holding the deflection yoke assembly.
White Balance Adjustment
Generally, white balance adjustment is made with professional equipment. It’s not practical to get good white balance only through manual adjustment. For TVs with I2C bus control, change the bus data to adjust white balance.

Schematic - Full

CIRCUIT ADJUSTMENT S
Preparation:
Circuit adjustments should be made only after completion of set-up adjustments.
Circuit adjustments can be performed using the adjustable components inside the TV set. For TVs with I2C bus control, first change the bus data.
1. Degaussing
A degaussing coil is built inside he TV set. Each time the TV is powered on, the degaussing coil will automatically degauss the TV. If the TV is magnetized by external strong magnetic field, causing color spot on the screen, use a specific degausser to demagnetize the TV in the following ways. Otherwise, color distortion will be shown on the screen.
1.1 Power on the TV set and operate it for at least 15 minutes.
1.2 Receive red full-field pattern.
1.3 Power on the specific degausser and face it to the TV screen.
1.4 Turn on the degausser. Slowly move it around the screen and slowly take it away from the TV.
1.5 Repeat the above steps until the TV is degaussed completely.
2. Supply Voltage Adjustment
Caution: +B voltage has close relation to high voltage. To prevent X-ray radiation, set +B voltage to the rated voltage.
2.1 Make sure that the supply voltage is within the range of the rated value.
2.2 Connect a digital voltmeter to the +B voltage output terminal of the TV set. Power on the TV and set the brightness and sub -brightness to minimum.
2.3 Regulate voltage adjustment components on the power PCB to make the voltmeter read 115±1V.
3. High Voltage Inspection
Measure voltages of test points on the main PCB with the digital voltmeter. Measure the CRT high voltage with the high-voltage testing equipment and heater voltage with the high-frequency effective voltmeter.

[Anode high voltage differs depending on CRTs used, which should be decided by engineers.]

Focus Adjustment
Caution: Dangerously high voltages are present inside the TV. Extreme caution should be exercised when working on the TV with the back removed.
1 After removing the back cover, look for the FBT on the main PCB. There should be a FCB on the FBT.
2 Power on the TV and preheat it for 15 min.
3 Receive a normal TV signal. Rotate knob of the FCB until you get a sharp picture.
5. Safety Inspection
1 Inspection for insulation and voltage-resistant
Perform safety test for all naked metal of the TV. Supply high voltage of 3000V AC, 50Hz (limit current of 10mA) between all naked metal and cold ground. Test every point for 3 min. and ensure no arcing and sparking.
2 Requirements for insulation resistance
Measure resistance between naked metal of the TV and feed end of the power cord to be infinity with a DC-500 high resistance meter and insulation resistance between the naked metal and degaussing coil to be over 20MΩ .
6. DESIGN/SERVICE mode
1 To enter the USER SERVICE mode
Caution: The user service mode adjustment can be changed only when service personnel adjust the whole set data during servicing. As the control data have dramatic effects on functions and performance of the TV, service personnel should not tell user how to enter the SERVICE mode to avoid improper data settings.
1.1 Set the volume to 0. Then press and hold the MUTE button on the remote control, and press the MENU button on the TV to enter the SERVICE mode. (In this case, the S mode cannot be stored in the EEPROM. To exit from the S mode, turn off the TV set. )
1.2 After entering the S mode, Red“ S”is displayed on the upper center of the screen and MENU1 is default. Use the POS+/- buttons to highlight an adjustment and the VOL+/- buttons to adjust it. The adjusted data are immediately output and stored in the EEPROM

Option set
With remote control system software TDA935X,all options can be set in the SERVICE mode and stored in EEPROM. Data related to picture, sound and geometric adjustment are also stored in EEPROM.

CHANGHONG LED32D2200 LED TV HLT57EJ CHASSIS SERVICE MODE, SOFTWARE UPDATE, POWER BOARD SCHEMATIC

Changhong LED color TV – how to enter the service mode, how to upgrade the software, SMPS circuit diagram – Chassis 920B, Model: HLT57EJ - PCB version JUC7.820.00117550-1

The high-voltage of the LED screen is generated by the power supply board, without attention to exposure to the high voltage, one may meet a serious electricity shock.

HDMI and YPbPr support to 1080P:
The recommended resolving ratio of PC is 1280X768.

Recommended operating power conditions
(The Main Chip cancel 1.8V Supply Voltages because of DDR3 supplied by 1.5V )

Terminals

Main IC HLT57EJ functions

Power supply and interface

Software upgrade- UART Upgrade

UART upgrade is very slow, about 15 minutes.

If main board is not dead, do not use UART upgrade.

Upgrade tool.

Connection reference and upgrade steps

Make sure the main board has not powered.  The main board should be in power down condition.

Open UART upgrade software tool: uart2spl_tool in PC.

Select correct common port.

Power ON the main board.

Select Restore page.

Click ‘Load’ button of CodeBin, to load the upgrade bin file.

Click ‘restore’.

Click ‘Enter’ to start the upgrading.

The processing bar at the bottom will show up.

First time is erasing the FLASH chip.

Second time is Programming.

Wait programming to finish.

When ‘Restore success’ window shows, press ‘Enter’ to exit the window.

Power Down the main board, and then Power up. That’s all.

USB Upgrade

Copy the bin file to upgrade to USP key root folder.

Make sure the main board is power OFF.

Put USB key to main board USB terminal [USB key has the upgrade bin file]

Power ON the main board, the LED on IR receiver should blink slowly.

Wait till the LED on IR receiver blinks quickly, which means upgrade is finished.

Disconnect the power supply. That’s all.

Because of initial time of some USB keys are longer, main board cannot detect the USB key when power supply.  If so, upgrade the main board in Factory Menu.

LED indication blinks, while upgrade.

When upgrading, LED will blink slowly every 1 second.

After successful upgrade, LED will blink quickly ever ¼ second.

If upgrade fails, red LED lights long time and green LED short time in cycle.

Upgrading procedure in Factory Menu.

Power ON the set.

Put the USB key to main board USB terminal.

Press remote control keys: SOURCE > 3 1 3 8 to enter the factory menu [service Mode]

Select the Upgrade > USB Upgrade > USB Upgrade Start.

The system auto loads the upgrade bin file, and start upgrading.  The processing bar will be shown and the LED on IR receiver will blink.

After the upgrade finish window show, Power down the TV; and Power ON again.

Thinking of don’t boot

The power is not connected.

Common problems and high voltage, high current wearing parts list.

Power board [SMPS] schematic

How to enter the [Factory Mode [Service Mode]

Switch on TV set, and make it works normally

Press the SOURCE key on the remote control.

Press number keys 3 1 3 8 on remote control to enter password. Finish entering the factory mode.

To quit the factory mode, press the EXIT key to exit source.

Set Reset all will clear the memory data, so do not set it unless it is needed; other setting items do not need setting.

Factory Menu settings

Setting method of factory menu

1. Choose setting item
Operators can choose setting item orderly with up and dn key, font having background display represents the item has been chosen. Press Right  key to enter sub directory. Use up and dn keys on remote control to make up or down option, and use right and left keys to set.
2. All the menu functions are opened in factory mode, item checking and effect testing can be done by using menu if it is needed.
3. Switching TV signal in factory mode can be done by directly pressing the number key. Press MENU key to back to the parent of working directory, press EXIT key to quit factory mode.

CHANGHONG LT52510F - AOC L52BS83FU -SMPS SCHEMATIC. 715T2919-1. COMPONENTS: IC901: UCC28019DR-IC902: STR-W6252-IC905: L6599D

Changhong LT52510F - AOC L52BS83FU -SMPS SCHEMATIC. 715T2919-1. Components: IC901: UCC28019DR-IC902: STR-W6252-IC905: L6599D

Changhong and AOC LCD TV - power supply circuit diagram. 715T2929-1

Schematic

Click on the circuit diagrams to magnify

CHANGHONG PF29GA18A – HOW TO ENTER SERVICE MODE – CIRCUIT DIAGRAM – 29 INCH COLOR TV.

Changhong PF29GA18A – How to enter service mode – circuit diagram – 29 inch color TV.

ETA-1D chassis is applied in PF29GA18A series.
By use of Toshiba V/C/D-MCU 2IN1 IC for TV small signal processing and bus control, the chassis enables TV tuning, adjustment, control and picture correction, featuring
high-integration, high-performance-to-price ratio and high-reliability and compact circuit with fewer external components. The chassis, widely used in small and medium TVs,
provides much more convenience for manufacturing and technical service. It includes:
2IN1 IC 8897PSBNG-4VB6 for PAL/NTSC small signal processing and bus control [TMPA8897CMANG /CPANG/CRANG /CSANG]
EEPROM AT24C16 for data memory
LA78041 for vertical output power amplifying
LA42102 for audio power amplifying
TA1343N for audio processor
FSCQ1265RTYDTU for power circuit adjustment and control.

BSC68DG (FBT)
Mask ROM: TMPA8897CPBNG (ROM size: 48k)
Mask ROM: TMPA8897CRBNG (ROM size: 56k)
Mask ROM: TMPA8897CSBNG (ROM size: 64k)
OTP ROM: TMPA8897PSBNG (ROM size: 64k)
Color systems: PAL, NTSC
Sound systems: D/K B/G I M
236 programs preset
AV stereo
I2C bus control
Electronic program table
Intelligent lock
Biorhythm
Calendar inquiry.

To enter the DESIGN/SERVICE mode
Set the volume to 0.

Press and hold the MUTE button on the remote control, and press the MENU button on the TV to enter the SERVICE mode.

In this case, blue “D” is displayed on the upper center of the screen.

To exit from the D mode, turn off the TV set by the POWER button on the remote control.

Caution: The user service mode adjustment can be changed only when service personnel adjust the whole set data during servicing. As the control data have dramatic effects on functions and performance of the TV, service personnel should not tell user how to enter the SERVICE mode to avoid improper data settings.

Circuit diagram

It’s impossible to check the power part separately from the main chassis board as the part is mounted on the main chassis board. The power components, etc. should be checked for burnout when power-on. If burned out, do not power on the TV again until the cause is found out.

SMPS and system-chroma junge circuit - Split

Click on the pictures to zoom in

HOW TO ENTER SERVICE MODE TO CROWN - CHANGHONG - CELESTIAL - CCE AND COMET TVs

HOW TO ENTER SERVICE MODE TO CROWN - CHANGHONG - CELESTIAL - CCE AND COMET TVs

CROWN_CHANGHONG _ CELESTIAL_CCE_COMET
CHANGHONG 21BM91

• Set the volume to no sound.
• Then press and hold the MUTE button on the remote control, and the MENU button on the TV simultaneously to enter the factory mode.
• In this case, red “S” is displayed on the upper center of the screen.
• To exit from the S mode, turn off the TV set by the POWER button on the remote control.
• Caution: The user service mode adjustment can be changed only when service personnel adjust the whole set data during servicing.
• As the control data have dramatic effects on functions and performance of the TV, service personnel should not tell user how to enter the SERVICE mode to avoid improper data settings.

CHANGHONG R2938D

• Decrease volume to no sound.
• Press the mute on remote control and menu button on TV panel at same time.
• "S" appears on the screen indicating that the TV is in service mode.
• To change and edit factory mode using pro+/- and vol +/-.
• Save and exit settings press power button on remote control.

COMET PT92J

• Press simultaneously Volume down button on TV Panel and SUBPAGE button on remote control.
• Press Program up and down to select and change value press volume button (+/-)
• To save and exit press TV button on remote control.

CELESTIAL 21B33

• Decrease volume to no sound, press and hold mute on remote control.
• Press Menu key on TV panel until menu and D sign appears.
• Use colored key to select and store settings.

CCE HPS2001

• On the TV motherboard press switch 702.
• To change and edit data value press Volume key and Program key.

CROWN 4K2822T

• Open the TV remote control.
• Entering service button located below stop button.
• Select press program +/-  to select an item to adjust.
• To change the data value press volume +/-.
• Save settings and exit press P.P button.

CROWN CM2007

• Open the remote, removing the top cover.
• Use the keys that have no access External and under "previous channel" and "Sound."
• Press channel + / - Select an item to adjust.
• Press the VOL + / - to adjust its value. 

CROWN CTT3207W LCD TV

• Get in on the main menu by pressing the M button on the remote control.
• Enter the digits [ 4, 7, 2, 5].
• To change the setting press the volume key.
• Press the program up or down to select the parameters.

Entering or making changes in service mode menu / item information service mode by untrained persons can cause significant or permanent damage to TV system. If you are not qualified to fix it, e DO NOT ENTER TV factory mode using these service menu codes, Call Center Service

HOW TO ENTER SERVICE MODE TO BANG & OLUFSEN - CHANGHONG - CROWN & BLACK DIAMOND TVs

HOW TO ENTER SERVICE MODE TO BANG & OLUFSEN - CHANGHONG - CROWN & BLACK DIAMOND TVs

Bang & Olufsen TV model LX4500, LX5500, LX5000, and LX6000

• Power ON the TV.
• Press TV on remote control and short the pin service mode plugged p700 on PCB14.
• Select press p+/p- button and change value pres v+/v- button.
• Save change and exit press STOP button on remote control.

CHANGHONG 21BM91

• To enter the DESIGN/SERVICE mode Set the volume to no sound.
• Then press and hold the MUTE button on the remote control, and press the MENU button on the TV to enter the factory mode.
• Red “S” is displayed on the upper center of the screen indicating that the TV is in service mode.
• To exit from the S mode, turn off the TV set by the POWER button on the remote control. 

CROWN CM-2007

• Open the remote, removing the top cover.
• Use the keys that have no access External and under "previous channel" and "Sound." Canal + / - Select the item with the VOL + / - adjusts its value. 

BLACK DIAMOND BDS1451UK

• To enter Black Diamond TV factory mode press Menu and press following key 4, 7, 2, 5.
• Factory mode load in 0.1 second,
• Use Red, Green, Blue, Yellow button to select and change.
• Save settings press Ok button.
• To exit from factory mode press MENU button.

HISENSE TF2906DU-A – H3498 - CHANGHONG CH-16 - SCHEMATIC DIAGRAM - UOC CHASSIS

HISENSE TF2906DU-A – H3498 - CHANGHONG CH-16 - SCHEMATIC DIAGRAM - UOC CHASSIS

SCHEMATIC DIAGRAM
Using ICs - HEF4094 – KA5Q1265RF Power Switching – HS817B Opto-coupler – TDA938x – TDA7495S – TDA8351

Click on Circuit to Magnify

CHANGHONG - 21NF55 _ 21PF93 – STR-G5653 _ SMPS SCHEMATIC (CIRCUIT DIAGRAM) _ SERVICE MODE

CHANGHONG - 21NF55 _ 21PF93 – STR-G5653 _ SMPS SCHEMATIC (Circuit diagram) _ SERVICE MODE

SMPS SCHEMATIC

CLICK ON THE PICTURES TO ZOOM IN

To enter the USER SERVICE mode

Caution: The user service mode adjustment can be changed only when service personnel adjust the whole set data during servicing. As the control data have dramatic effects on functions and performance of the TV, service personnel should not tell user how to enter the SERVICE mode to avoid improper data settings.

• Set the volume to [0]. Then press and hold the MUTE button on the remote control, and  press the MENU button on the TV to enter the SERVICE mode . (In this case, the S mode cannot be stored in the EEPROM. 
• To exit from the S mode, turn off the TV set.)
• After entering the S mode, Red  “S” is displayed on the upper center of the screen and MENU1 is default.  Use the POS [+/ -] buttons to highlight an adjustment and the VOL[+/-]   buttons to adjust it. The adjusted data are immediately output and stored in the EEPROM.

Adjustment and Option Data in S mode

• The items remarked with “ *” , not affecting functions of the whole set, can be adjusted depending on models.
• The items remarked with “ ***” , affecting functions of the whole set, can be adjusted depending on functions of models.
• To write in logo, use the  ↓/ ↑buttons to highlight an adjustment and the  < -- / à  buttons to adjust.
• The data sheet may differ dependent on different models.
• The data sheet may differ dependent on different CRTs for the same model.

KEY ICS TECHNICAL DATA

The super chips  TDA935X/6X/8X are good in pins compatibility. Differences among them are shown as follows.

 

TDA9351   48K   PAL/NTSC/SECAM+1 PAGE TELETEST
TDA9350   48K   PAL/NTSC+1 PAGE TELETEST
TDA9361   64K   PAL/NTSC/SECAM+10 PAGE TELETEST
TDA9360   64K   PAL/NTSC+10 PAGE TELETEST
TDA9380   32K   PAL/NTSC
TDA9387   32K   NTSC

CHANGHONG - CN 18EAV2 R2938D SERVICE MODE

                                 TO ENTER SERVICE MODE

• Press Volume down button to make volume level to minimum [0].
• Press and Hold the 'Mute" button on the remote control
• While holding down the 'Mute' button on the remote control, press "Menu" button on the TV control panel.
• A Red "S" will be displayed on the upper portion of the screen.
• To call an item to adjust, use "Prog + / Prog -" button on the remote control.
• To adjust the data value to selected item, use "Volume Up / Volume Dn" button on the remote control.
• To Save and "Exit" service mode, press "Power" button on the remote control.

LCD TV REPAIR TIPS

LCD TV Repair Tips and tricks

Bush, Acer, Changhong, Sony, Philips, Goodmans, Sharp, JVC and more.

Wharfedale LCD3210AF Chassis 17MB116 LCD TV Starts-up, backlight came after that switches off immediately.
Starts-up, backlight came after that switches off immediately.  Runs ok when inverter board is externally supplied with 24v.
> Replace C877 and C878 (15nf/630v) between heatsink of switching transistor and larger transformer on the primary side of the PSU.

Vizio VO42LFHDTV10A LCD TV
Green distortion in the picture.
> If PSU secondary side voltages OK. Check & clean contacts of ribbon cables coming from control board.

GOODMANS GTV32W22HD AVZOOO Chassis LM
Dark picture. OSD bounces
> Replace C2042 and C2044 (680uf) in PSU.

Changhong LT32700 LCD TV
TV stuck on standby mode.
After the AC power supply to the TV, standby LED light on with yellow color. When press the power on switch or remote control power on, the TV still remain the same yellow color LED light and can’t start-up.
> Check the PSU output, their standby 5V is present but no any POWER_ON signal present. Checking their main board voltage regulator IC output and found U1 (LM1084-2.5) output voltage as 4V! Actually it should be output 2.5V instead of 4V. After replace U1 the TV is working.

Changhong LT2612 LCD TV (T-con: SVA 260PW023S)
No Display and the screen full of Vertical color lines
> Normally this type of TV symptom was causing by the T-CON board or LCD panel. This LCD Tv using SVA 260PW023S T-CON board. Check the T-con board Vcc voltage input had 5V, and the AVDD had 3.3V. The lcd panel driving voltage VGH & VGL are nothing. Suspect their DC-DC circuit lines having problem. Check the VGH line with GND with ohm range, it had 300 ohm only. But VGL line with GND had above 36K ohm! So suspect the VGH circuit line filter capacitor leakage. Found three SMD chocolate color filter caps on the VGH line and two of three filter caps were leakage, another good one got 3.3uF. Because of they are three same size and color filter caps, so using one normal electrolytic capacitor 10uF/50V to replace it. Power on the TV their display is back to normal.

Changhong LT24720FX LCD TV
Display poor image with whitish tail or ghosting
> Normally this type of symptom was causing by the T-CON board or LCD panel. So starting testing their T-CON board voltage and found that VGH voltage has 2.3V only. The correct VGH voltage for this T-Con board should be about 25V. At the same time found a burnt component on the T-con and the location is R100. That’s mean it is a burnt resistor and can’t saw any value there. Using multimeter ohm range to checking the R100 pin ohm values to GND (ground) is about +/- 500K ohm. This is let us know, the R100 position not because of other components short circuit and causing it burnt. Use a 1M ohm variable resistor (VR), starting from the highest ohm first and then slowly decreases the ohm values until the VGH reach 25V and the display also change to normal. So check on that VR and found it is about 100K ohm, after that changed a SMD resistor with values 100K ohm to R100. The VGH line got 25V now and the display image also back to normal now. The TV problem solved.

Konka LC32ES62 LCD TV

TV Randomly Can’t Start-up, LED light blinking non-stop with Red and Green color). Or when TV heat the backlight flickering till no backlight/cut off and the sound remain ok.
> This TV is using the IP (Inverter Power Supply board) board with LG LCD Panel. Find a resistor R756 in IP board and modify it to 3.3K ohm and problem solved.

BUSH LCD32TV005HD: BUSH LCD32TV005HD APH000 Chassis BEKO LM LCD TV 

After TV on few seconds, then the TV off again.
Picture appears for a few seconds after switch on, after that the TV switches off again.
> Check C2042 and C2044 (both 680uf/35v) in PSU for capacity loss.

BUSH LCD32TV005HD: No Picture and no back light. Front controls react and remote control does not.
BUSH LCD32TV005HD APH000 Chassis BEKO LM LCD TV
No Picture and no backlight. The front controls was working but remote control does not
> Replace IR receiver (short circuit).

JVC LT32DX7B: No functions after lightning strike
JVC LT32DX7B LCD TV
Symptom: No functions after lightning strike.
The primary voltage 300v is present. But secondary voltage output was only 21 volt. Replace standby transformer T9201.

Sharp LC32P55E: Red LED appears for a seconds, relay clicks then dead.
Sharp LC32P55E LCD TV: Red LED appears for a seconds, relay clicks then dead.
> The resistor R751 blown. Replace IC704 & R751.

Sharp LC32P55E: Dead after start-up. Bang-noise head before
Dead after start-up. Bang-noise head before.
> Replace R751 (0.1R/2W), IC704, D762, D725 and C725 (470pF/3K) in PSU.

Philips Chassis BJ3.0E LA: Switches off for a second or two intermittently
Philips Chassis BJ3.0E LA LCD TV
Switches off for a second or two intermittently. Relay clicks and standby LED remains green. Switches off intermittently with green LED on, no sound or no picture.
> Check the 27MHz KDS quartz crystal (SSB, item 1H00). If all yellow marked crystals bearing with a "5E", "5J" or "5K" batch number direct replace it. Also replace all the silver marked crystals bearing with a "6D" batch number.

ACER AL2671W LCD TV
Dead.
> Replace power supply IC (TNY264PN) and resistor R60 (10R/0.33W, NFR type).

ACER AL2671W: No start-up. LED is orange
No start-up. LED is orange.
> When C380 unsuccessfully replaced. Standby PSU functions and standby 5V present. The voltage appears at pin “PSON” in the PSU after switch on but PSU does not start. Actually they are three 330K SMD resistors in series in the PSU which supply voltage for DLA001. Check if resistors are high resistive.

Bush IDLCD26TV05HD: No backlight and no picture. Sound ok and can be intermittently
Bush IDLCD26TV05HD Chassis L9 (Beko) LCD TV
No backlight and no picture. Sound ok and can be intermittently.
> Replace C512, C513 (both 1000uF/35v) and C519 (220uF/35v) in PSU. Also a 1000uf/16v capacitor on the signals board on the far right-hand side, near the top.

SONY KDL40U2000 with SE1 Chassis LCD TV.  No start-up, red LED flashes 3 times.
> TV has slow start-up before this symptom occurred. When check standby 5V ok and PSU is heat sensitive. Check and replace the C6055 (47uf/25v) in G2 supply it will solve the problem.

BUSH LCD32TV022HD: Intermittently no start-up or dead after a few hours
BUSH LCD32TV022HD with 17MB15 Chassis LCD TV intermittently no start-up or dead after a few hours.
> The PSU replaced and EEPROM IC resoldered, but on help. Try to resolder IC220 (SDA5550) and IC224 on main board the TV back to normal.

EVESHAM ALQEM37SX: No start-up, the TV screen lights up, then switches back to standby mode
EVESHAM ALQEM37SX with 17MB15 Chassis LCD TV
No start-up, the TV screen lights up, then switches back to standby mode.
> Check or direct replace the C877 and C878 on PSU board for open circuits. Sometime these caps will check good, but would breaks down under load.

Grundig GULENAR32HDIP with Chassis L9 LCD TV:  Stuck in standby mode, LED light is blue color.
> The blue LED always stays on, even when appliance is on standby mode. Capacitor C931 (1000uF) replaced but appliance is still dead with 12V and 24V ok. Check and replace diode D300 on the right-hand side, on mid -top of the main board.

ACER AL2671W: No start-up. LED is orange
Acer AL2671W LCD TV
No start-up. LED is orange.
> Check C380 (100uf.16v) under heatsink, next to U42 and U61 on signal PCB for capacity loss.

Sony KDL32U2000: No Picture
Sony KDL32U2000 Chassis SE1 LCD TV
No Picture
> Check SMD fuse CP101P on LVDS board. The LVDS board is behind the BDT board.

SONY KDL32S2010E: Switches to standby for a short while, then back again
SONY KDL32S2010E Chassis WAX2 LCD TV
Switches to standby for a short while, then back again
> Replace standby push button on user control, has contact resistance.

Philips 32PF3320/10: "F" is displayed on screen
Philips 32PF3320/10 Chassis LC4.5 EAA LCD TV
"F" is displayed on screen
> TV is in factory mode. To quit the factory mode, press both "VOLUME" "-" keys and "PROGRAM" "-" for 5 seconds simultaneously.

LG 32LC56: Picture divided into several parts. Distorted picture
LG 32LC56 LCD TV
Picture divided into several parts. Distorted picture
> Replace T-CON board (Part Number: 218394).

LG 32LC56ZC: No start-up. Standby LED flashes from red to green
LG 32LC56ZC LCD TV
No start-up. Standby LED flashes from red to green
> Replace C202, C206, C217 and C218 (2200uf/10v all), and C226 (470uf/25v).

GOODMANS GTV26WLCD: Shuts down and LED blinks
GOODMANS GTV26WLCD LCD TV
Shuts down and LED blinks
> Replace C877 and C878 (both 15nf/630V) near heatsink, at top left corner of PSU

BUSH LCD26TV006HDX: No display. Flashing standby light
BUSH LCD26TV006HDX LCD TV
No display. Flashing standby light.
> The capacitor C315 (1000uF/25v) is supplied higher rated, and is a little bigger so use longer leads don't fit close to board. Be careful when soldering you don't accidentally remove the tiny surface mount resistors on back of board.

Hitachi 37LD6600: No sound or intermittent sound
Hitachi 37LD6600, 37LD6600A LCD TV
No sound or intermittent sound
Pins of headphone socket touching the chassis.
> Trim the pins of the Headphone socket.

Hitachi 37LD6600: MECHANICAL NOISE FROM SCREEN ONLY IN CINEMA MODE
Hitachi 37LD6600, 37LD6600A LCD TV.
MECHANICAL NOISE FROM SCREEN ONLY IN CINEMA MODE
High back light setting on Cinema mode.
Backlight settings are different for each mode :
DYNAMIC: 00
NATURAL: 50
CINEMA : 100
> Reduce backlight settings in Cinema mode from 100 to 59 as follows.
Enter Service Mode with the remote control,
PRESS MENU; 4725 OR 1267 OR 1461 (there are 3 different software versions, only one code will work)
Service Menu will appear, Select PIC ADJUST and enter with VOL+
A second service menu will appear, the bottom adjustment in the menu is Back Light setting and will be set to 100.
From the Mode Heading select CINEMA mode.
Select Back Light and reduce the setting to 59.
To memorize and exit Service Mode press Standby.

Hitachi 32LD7200: Distorted Sound/Audio
Distorted Sound/Audio
Sound is distorted when the set is first switched on. After a while the fault clears and the set works normally.
> Replace Joint PWB. P/N: TP01336.

Hitachi 32LD7200: MECHNICAL NOISE FROM SCREEN IN DYNAMIC MODE
Low back light setting on Dynamic mode.
Backlight settings are different for each mode :
DYNAMIC : 12
NATURAL : 15
CINEMA : 10
Cure/Solutions: Increase backlight settings in Dynamic mode from 12 to 20
If similar noise problem occurs on other modes, adjust backlight levels to the position in which noise becomes minimum..
ADJUSTMENT
Backlight level can be adjusted in USER menu only.
Select Menu => Picture => Backlight => and adjust as necessary.

Hitachi 32LD6600: No picture, but sound ok
Hitachi 32LD6600_A_B_C LCD T V
No picture, but sound ok.
> Dry joints on components S627 and S629 near connector PL308 on the main board.
Cure/Solutions: Resolder components S627 and S629 and also check other components for dry joints near the connector.

Hitachi 32LD6200: Unit does not switch on or fails to power on
Hitachi 32LD6200_A_B_C LCD TV
Unit does not switch on or fails to power on
Unit does not work, standby LED not lighting.
Working of Pixelworks controller IC21 depends on ambient temperature.  If the IC is heated externally the unit starts to work normally.
> Replace Ferrite bead L500 and L501 with a jumper wire.

Hitachi 32LD6200: Set fails to power on/switch on
Model/s: Hitachi 32LD6200_A_B_C LCD TV
Symptom: Set fails to power on/switch on.
If MB11-6 Main board is used instead of the original Main board MB11-2 the unit won't switch on.
Unit switches off immediately and a clicking noise comes from the Power Regulator Board.
> Replace the LVDS cable (p/n: VS30041693) and add a 47uF(p/n: VS30000396, CAP EL47UF16V) electrolytic capacitor to Power Regulation Board .

Hitachi: Picture Display Problem
Model/s: Hitachi 32LD6200_A_B_C, 32LD6600_A_B_C LCD TV
Symptom: Picture Display Problem
Cause: Various picture problems can be caused by poor connection of the LVDS cable on connector PL103 on the Main board.
> Remove LVDS cable from connector PL103 and reinsert carefully.
Make sure both end of the LVDS cable are inserted properly between PL103 and the display panel.

Sharp: The Sharp LCD TV still under protection mode?
Model/s: SHARP LCD TV Repair tips
Symptom: The Sharp LCD TV still under protection mode?
The Sharp LCD TV always have the protection mode come out. Normally, the repairer will first check the inverter board, after that power board/PSU, if still can't get any result, then they will check the signal board or mainboard. Even you change the inverter or PSU board, the lcd TV still under protection mode. Sometime, the lcd TV has been fixed by the repairer, but they don't know the TV still remember the protection mode inside the memory. So, now you need to know how to clear this protection error inside the lcd TV memory.
> Press & hold the CHANNEL DOWN & VOLUME UP buttons, then ON the LCD TV. The LCD TV Protection Error has been clear & solve the TV problem.

Hyundai: Slow start-up
Model/s: Hyundai Imagequest HQL260WR LCD TV
Symptom: Slow start-up
> Replace capacitor C109, C110 and C111 (all 1000uf/35v). Also check SMD resistor R56 and R57(both 22K) for dry joints.

Hyundai: Shuts down after a few minutes
Model/s: Hyundai Imagequest HQL260WR LCD TV
Symptom: Shuts down after a few minutes
Three 1000uf electronic capacitors in PSU replaced unsuccessfully.
> Change optocoupler IC PC102-2.

LOGIK: No sound or picture. The front controls light up & relay clicks.
Logik LCXW32HDI LCD TV
No sound or picture. The front controls light up & relay clicks.
> Check or replace R65 (2M) in U3 PSU for open circuit.

Panasonic: Enter Service Mode.
Panasonic TX-32LED7FM Chassis GLP22M LCD TV
Enter Service Mode.
1. Press F button to access volume setting.
2. Press V- button on set until volume reaches minimum.
3. While still holding V- button press 0 button three times on remote control.
4. Press 1 and 2 buttons to scroll through the menu.
5. Press 3 and 4 buttons to select an adjustment.

Philips: Picture jitter if contrast function is used.
Philips 23PF9966/37 LCD TV
Picture jitter if contrast function is used.
> Replace transistor 7563 on Scaler board.

Philips: No sound
Philips 23MW9010/37 LCD TV
No sound
> Defective sound output IC7731 (AN7522).

Philips: Stuck in standby
Philips 42PF7621/D10 LCD TV
Stuck in standby. Switches to protection mode. Green LED flashes.
> Replace capacitors 2540 and 2544 (both 10nF). Change to both with 220nF.


Philips: High pitched noise coming from LCD supply
Philips 42PF7621/D10 LCD TV
High pitched noise coming from LCD supply
> Check or replace 5025, 5026 and 5027 at LCD supply and glue them if necessary.

Philips: Switches off for a second or two intermittently.
Philips Chassis BJ3.0E_LA LCD TV
Switches off for a second or two intermittently.
Relay clicks and standby LED remains green. Switches off intermittently with green LED on, no sound or picture.
> Check 27MHz KDS quartz crystal (SSB, item 1H00). Replace all yellow marked crystals (made in China) bearing a "5E", "5J" or "5K" batch number. Also replace all silver marked crystals (made in Taiwan) bearing a "6D" batch number. Note: Replace crystals with order code 242254301397.

Polaroid: No Start-up
Polaroid FLM3232 LCD TV
Symptom: No startup.
> Replace Z9 zener diode with NTEPN4990 in the PSU.

SONY: Stuck in standby. Standby LED is green.
Sony KDL32U2000 Chassis SE1 LCD TV
Symptom: Stuck in standby. Standby LED is green.
Red LED flashes 3 times. No remote control or front panel functions.
> Check or replace D301 zener diode (can be use a 5v zener diode) for short circuit.

SONY: Error code 4
SONY KDL40U2000 LCD TV
Error codes 4
LED turns green, flashes 4 times then goes green again and flashes 4 times again. Fuse (500mA) on inverter panel open circuit.
> Replace the fuse on inverter board.

SONY: No start-up. Red LED flashes 3 times.
SONY KDL40U2000 LCD TV
No start-up. Red LED flashes 3 times.
Slow start-up before this symptom occurred. The standby 5v ok. PSU heat sensitive.
> Check C6055 (47uf/25v) in G2 supply.

Toshiba: Dead
Toshiba 32WLT58 LCD TV
Dead
> Check F870 (2A), Q860 (STRZ4479) and D866. If F801 open circuit, then check the voltage regulator Q820 for short circuit, R831 (4.7R/5W) and D825 (MTZJ33A).

Viewsonic: Picture flickers and is brighter on the right, than on the left
Viewsonic N3260W VS114361M LCD TV
Picture flickers and is brighter on the right, than on the left.
> Replace four electrolytic capacitors (2x 820uF and 2x 1000uF) in upper left PSU.

Viewsonic: No startup
Viewsonic N3260W VS114361M LCD TV
No startup
> Check capacitors (with ESR Capacitor tester), Q7 and SMD resistor R65 (5.1R) in primary side of PSU. This TV set using the FSP228-3F01 PSU.

Westinghouse: Blue screen. No sound, no picture and no OSD
Westinghouse LTV40W1HDC LCD TV
Blue screen. No sound, no picture and no OSD.
> Replace circuit protector fuse on T-CON board.

Dell W2600: Erratic functions
Dell W2600 LCD TV
Erratic functions.
Sometime the TV locks-up problem shuts down, no start-up and no remote control or front panel functions too.
> Resolder or reflow system ROM IC1234 and all regulator ICs on the main board.

DELL W2600: Display locks after 10 minutes
Dell W2600 LCD TV
Locks after 10 minutes
> Change regulator IC (LM1117 DT-2.5) on main board.

DELL W2600: No start-up after warm-up
Dell W2600 LCD TV
No start-up after warm-up
> Replace capacitor (10uf/50v) on small board mounted to power supply next to main board power connector.

Acer AT3201W LCD TV
No function on user control and remote control
No function on user control and remote control
When SCART module removed, remote control reaction ok.
> Replace electrolytic capacitors C348 and C350 (both 220uF/16v) on main board.

Bush IDLCD26TV05HD Chassis L9 LCD TV
BUSH: No Backlight
No Backlight
There is no 24v to the inverter board after a while. Sensitive to power supply tapping.
> Check & replace SMD 27v zener diode (red with yellow bands). Note: There are no reference numbers on any of the SMD components. The diode is located in primary side of the 24v chopper transformer supply, near pin5-8 of the SMD IC (UC3843A). (This PSU board is GDP002 ZR1910R NETZTEIL SPS 180W 24/5 12/5 PFC 2PIN(LISH)).

Hitachi 28LD5200E LCD TV
Intermittent Color or no color
Intermittent Color or no color.   Color drops out after the unit has been running for two to three hours.
> Resolder capacitor C510 and other components in its vicinity.

Hitachi 26LD6600 & 26LD6600A_B_C_D, 32LD8A10, 37LD6600, 37LD6600A & 37LD8500, 37LD8550, 37LD8600, 37LD8700C, 37LD8700CA, 37LD8700U, 37LD8700UA, 37LD8A20, 37LD8D10, 37LD8D20E, 37LD8D20U LCD TV
Poor image quality or polarization of image
Poor image quality or polarization of image
This phenomenon may be very intermittent and only displayed after a number of hours/days on soak
Cause: The glue on the LDVS cable heats up over time and the properties change and creating a contact problem within the cable and the PCB. This causes permanent or intermittent picture problems
> Remove the LDVS cable and clean the connections at the LCD control panel and replace the LVDS cable.

Hitachi 26LD6600 & 26LD6600A_B_C_D LCD TV
Hitachi: SOCKET CHANGE ON POWER BOARD 17PW15-9
Tip: SOCKET CHANGE ON POWER BOARD 17PW15-9
Change: On the new version of Power Board 17PW15-9, socket PL805 has been changed to a 13 pin. On the earlier version of the power board socket PL805 is 12 pin.
When new Power Board with 13 pin ( PL805 socket ) is fitted to a set, the connector lead from socket PL805 must be changed .

Hitachi 26LD6600 & 26LD6600A_B_C_D, 32LD8A10 LCD TV
CHANGE OF POWER SUPPLY FROM TYPE 17PW15-8 & 17PW15-9 TO 17PW20
Model/s: Tip: CHANGE OF POWER SUPPLY FROM TYPE 17PW15-8 & 17PW15-9 TO 17PW20
The original power supply, version 17PW15-8 & 17PW15-9 has now been changed to the later version 17PW20
When fitting the new power supply, it may also be necessary to replace two cables with a new type as described below.
There is one new part number to replace all. This new part number will supply a kit that includes the power supply and the necessary new cable which you should use if required.
Remove the following connecting leads used with Power board 17PW15-8
1.Remove cable from Power board connector PL806 going to Mainboards MB15E-5 or MB15E-7 connector PL902.
2. Remove cable from Power board connector PL805 going to Mainboards MB15E-5 or MB15E-7 connector PL900 .
Replace the two cables with the new cable type:
Order New cable part number VS30049856
CHANGES:
Insert new cable:
1. On the Power Board Connect 12 pin connector of the new cable to PL805
2. On the Main Board: Connect the 7 pin connector of the new cable to PL902 and 12 pin connector to PL900.

Hitachi 26LD6600 & 26LD6600A_B_C_D, 32LD8A10, 37LD6600, 37LD6600A, 37LD8600, 37LD8700C, 37LD8700U LCD TVs
Hitachi: FITTING NEW MAIN BOARD TYPE MB15E-7
Tip: FITTING NEW MAIN BOARD TYPE MB15E-7
When new Main board type MB15E-7 is replaced instead of Main board type MB15E-5 the following changes have to be made.
REMOVE PARTS:
1. Remove and discard cable between Audio board (AMP05) connector PL709 and Main board connector PL1001.
2. Remove and discard cable between Audio board (AMP05) connector PL704 to main board connector PL903
CHANGES:
Order New cable part number VS30051586
Insert new cable:
On the main PCB Connect 6 pin connector of the new cable to PL1004.
On the Audio PCB you must first Check the version of Audio PCB fitted to the TV.
For Audio PCB version AMP05: Connect the 5 pin connector of the new cable to PL709 and 2 pin connector to PL704
For Audio PCB Version AMP03 : Connect the 5 pin connector of the new cable to PL709. As PL704 does not exist on this version the 2 pin connector must be removed and the cable then soldered to legs of D700 and D701.
New Chassis Version MB15E-7 changed in production as table below
Model Part Number Serial Number (From ~)
32LD8600A VS20286080 V61101471 ~ 32LD8A10A VS20286080 V61101681

Hitachi 26LD6600 & 26LD6600A, 32LD6600_A_B_C LCD TV
Symptom: No sound/audio
Cause: Sound setting may have been lost in the memory and defaulted to zero.
> Reinstate sound settings as follows:
Enter Service mode.
Press Menu then 4,7,2,5.
Go to Audio menu.
Select Sound 2. and enter the following values:
FM PRESCALER 15
NICAM PRESCALE AVL ON 35
SCART PRESCALE AVL ON 14
SCART VOLUME AVL ON 122
GO TO STANDBY TO MEMORISE SETTINGS

Hitachi: Burn in Mode when replacing Main PCB: Hitachi 26LD6600 & 26LD6600A, 32LD6600_A_B_C, 37LD6600 LCD TV
Tip: Burn in Mode when replacing Main PCB
When replacing the main PCB on these models, the new part may be in the 'burn in' mode from manufacture. This will result in the image on screen flashing different colors.
To exit the burn in mode:
Use the remote control :
1. Press menu button
2. Press the following button sequence: 4,7,2,5 :
3. Go to “OPTIONS” and then set “BURN IN MODE” to either ON or OFF.

Hitachi 26LD6200 LCD TV
Audio noise may be heard from speakers when unit is in Tuner mode
Audio noise may be heard from speakers when unit is in Tuner mode and the volume control is set to near minimum.
> Add four SMD jumpers on the Amp board to positions J100, J101, J102 and J103 (JUMPER SMD 0603 R).

Hitachi: Retune of Digital TV channels
Hitachi 22LD4500UK LCD TV
Tip: Retune of Digital TV channels
1. Press the menu button on the remote control to display the main menu on screen
2. Use the cursor down button on the remote control to highlight 'Installation' and then press OK
3. “Your previous digital channel list will be destroyed. Are you sure……” This message will appear on screen, select yes using the left cursor button and press OK
4. All channels will automatically be installed.

Hitachi 22LD4500U, 22LD4500UK LCD TV
No sound or very low sound on terrestrial and no sound on Digital or any AV inputs.
Cure/Solutions: This is a software/firmware problem. Replace memory IC302 Type 24LC16 (part number: VS20167612). All customer controls are set to minimum on the new IC. Please reset language and all picture controls to normal after replacing the IC.

Hitachi 22LD4200 LCD TV
Green horizontal line flashing across the screen intermittently
> Remove resistor R149 on the Input signal board (Signal processing-analog) and replace it with Jumper SMD( 0 ohm, partnumber: VS30001734).

Hitachi L32VP03E, L32VP03U LCD TV
No Switch on from standby
No Switch on from standby
If the TV is switched into standby when it has been running for some time and is warm, it will not come out of standby until the set has cooled completely
> Replace the crystal X104 (XTAL 14.318MHZ 20PF 20PPM SMD ROHS, part number: VS30054926) on the main PCB/main logic board, the system control section.

Hitachi L32A01, L32A01A, L32H01E, L32H01EA, L32H01U, L32H01UA, 32LD8D20E_EA, 32LD8D20U, 32LD8D20UA LCD TVs.
Audio is distorted constantly and may have some background noise
> Replace D845 and D846 (both UF5402 3A/200V 150A, part number: VS30009366) on the power supply board/PSU.

AMOI 32K1 LCD TV
No Display and No Sound
> When press on the standby mode button, LED light change from Red to Blue color but no backlight. Try to using a wire with a resistor connect the 3.3V to BL_ON signal, their backlight and screen logo AMOI are present but all front buttons and control no functions.
Replace the main board EEPROM IC 24C32, using a programmer to empty their Data and then solder it back to main board.

Philips 20PF5120/93 Chassis ML1.1A AA LCD TV
Randomly No Display but Sound Normal
> Find this R54 (54.9K ohm) resistor and replace it with a 75K ohm resistor on main board.

Philips 32PF7321/93 Chassis LC4.31A AA LCD TV
Sound Distorted
> Replace 2013 ceramic capacitor from 1.5nF to 10nF/50V ceramic capacitor.

Philips 42TA2000/93 Chassis TPT1.0A LA LCD TV
Display and Backlight flickering
> If capacitor on position 2083 positive pin is 24V and drops to ~20V, so measuring the capacitor on 2079, 2081 & 2082 with ESR tester or replace these 4 capacitor at the same time and problem solved.

Sharp LC26SA1E, LC26SD1E, LC32SA1E, LC32SD1E, LC42SA1E, LC42SD1E LCD TV
No Display, Sound Problem or Various operational key issues
> If after checking the whole PCB boards in TV still not solve the problem, it could be software issues.
Update the main software to the latest version, following the instructions in the service manual. Or using an ISP Programmer to empty their EEPROM IC first, if problem still the same, then you should program their flash memory by ISP Programmer with the working firmware.

Sharp LC46D78UN & LC52D78UN LCD TV
HDMI Connectivity Issues: No Sound or No Display When Turned On
In some cases, when connected via HDMI to an external audio amplifier or set top box an interruption to the sound and display may result when the TV us turned off and back on. This may occur due to current leakage from the HDMI-SW IC VHISII9287+-1Q on the mainboard.
> When the TV set requires service due to the above mentioned symptom, replace C1614 (0.1uF, 104 ceramic capacitor) on the mainboard with a 1K ohm1/16W resistor to reduce the leakage effect or just replace the main board.

Sharp LCD-37GA5 LCD TV
Stuck in Standby mode.
The LED light lit with Red color and its show on standby mode. Even press the power on button or using remote control also cannot power up the TV.
> After testing the PSU board, their standby 5V present and BL_ON signal (3.16V) was sent from main board to inverter board. And then their main chipset, Vcc voltage, clock or crystal waveform and reset circuit all normal, so that’s mean their main chipset is working properly. But their POWER_ON signal is missing and not present on the switch transistor to drive the RL701 to start-up the PSU.
From the previous experience, if all section in good condition but still no start-up, then it could be their MCU chipset or external flash memory (or their firmware corrupted) defective. Because of the Sharp LCDTV have lots of this problem was causing by their flash memory firmware corrupted. So checking the flash memory firmware first and found it was in IC3001 (L64) position. After solder it out, using an ISP programmer to backup their original firmware first. In case it is not the flash memory problem, then you can program it back to original version firmware. After that, find a correct version & working firmware and using the ISP programmer to program it into the L64 flash memory IC. Solder back this L64 flash memory into the mainboard. Power on this Sharp LCD-37GA5 LCD TV and it is working perfectly now! Problem solved and confirmed it was the firmware corrupted till it can’t start-up the power supply.

24E60HR LED TV
No Backlight or Display Dim
> This symptom is a common fault for this LED TV. Their problem was causing by LED Inverter/Drive board. When testing the LED Drive board C1 voltage, it is just 24V only. That’s mean their LED Drive board not working. Try to re-solder the LED Drive board U01, U02 and their surrounding components. After solder the board, their LED backlight is working now.

Skyworth 55LED10 Chassis 8K81 LED TV
Hard to start-up the TV when first time power it on.
When this LED TV every day first time power on, it is hard to start-up the TV. Check their 24V is ok but 12V output just have about 6~7 V only.
> This TV is using the ChiMei lcd panel and their PSU board is use 168P55PTQC-00. The PSU 12V output is from 24V through a DC-DC circuit generated. Change the R212 from 10 ohm to 0 ohm and R214 from 10 ohm to 4.7 ohm.

SONY KLV-26S550A, KLV-32S550A, KLV-37S550A LCD TV
Flashing and Jittering Display
When watching certain channels in RF mode, the picture may be flashing and jittering intermittently.
Cause: Abnormal signal condition- the problem channel has a wider H-sync width compared to the SECAM standard signal (difference up to 1,2us)
> Update the firmware to the latest version. In case of a 32 inch panel, first check the panel type before updating.

Sony KLV-32G480A LCD TV
No Display but sound ok and backlight working.
The screen has a “TV” character on the screen but no display, just black screen.
> Since this LCD TV sound and backlight ok, so the problem should be on the mainboard. Using volt meter testing the T-CON board Vcc line and it has 12V there. So the problem could be the mainboard Scaler IC, MCU, Flash memory, EERPOM or T-CON board. After testing the Scaler IC & MCU corresponding circuits like reset, Vcc and crystal all looking well. So try to check the flash memory & eeprom IC. Found these ICs were beneath of the mainboard. The IC3001 is 25L08 flash memory IC and IC3002 is 24C64 eeprom IC. So start the easy one, remove IC3002 (24C64) and using programmer to save their original data first and then erase this eeprom IC till it empty and all show “FF” on the programmer software. Solder 24C64 eeprom IC back to mainboard and power on the LCD TV. The TV screen can show a perfect display now and problem solved.