Monday, May 23, 2016

LCD TV Repair Tips

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.

Sunday, May 22, 2016

Hisense LCD TV – Service Tips

Hisense LCD4204EU LCD TV 
Dead with a Bang Noise
> Replace chopper drive STRX6769, RE038 (10R) and RE032 (150R) in primary PSU.
Hisense TLM3237D LCD TV
TV Power On then Shut Down
> Check the PSU board standby 5V STB normal and stable. But their POWER_ON signal is unstable, change in between 0~4.8V. Normally this POWER_ON signal is about 4.6V for this TV. So the problem was in main board or CPU section. Check their main board Voltage Regulator IC output voltages all normal and stable. Empty the U11 (24C32) EEPROM but not help. Testing the SCL & SDA line voltages it shows in between 0V~3.3V. Test the crystal Y2 (14.318MHz) it have 1.5V and another side is 1.7V. Use the ISP Programmer to program the correct version firmware into the main board flash memory U10 (PS25VF040). Power on the TV and the TV is working. After that, using remote control to control the TV function and their setting but it is hard to operate and slow motion to change function. Power off TV and then power it on again, the TV back to their original fault. 

Replaced a new flash memory U10 (Cannot use the empty flash memory and it can’t start-up the TV, must using the ISP Programmer to copy their firmware into it) and solder it back to main board. Finally the problem solved.
ChiMei V320B1-L06 LCD Panel with T-con board V320B1-C03
Screen fully with Vertical Color Lines
> This T-con board Vcc voltage is present. Check VDA voltage is 11.2V only. That’s mean their DC-DC circuit not working. Since their DC-DC IC AT1380A is control by the Timing Control chipset (CM2681A), when checking their switch on signal from CM2681A, it is no any signal from it. After that checking the CM2681A voltage supply IC N7 (2.5V voltage regulator IC) and found that has 0.9V volt output only instead of 2.5V. After replace this N7 IC , the screen is back to normal now.
Hisense TLM3226 LCD TV (T-CON: ChiMei V320B1-C03)
No Display

The TV sound normal and it can control by the remote control. Backlight is present but the screen no display and look like grey screen (because the backlight was working).

> This LCD panel using ChiMei V320B1-C03 T-CON board. So first check their Vcc input and other voltage values. Vcc input 5V ok, voltage regulator output 2.5V & 3.3V normal. When measuring the VDA, VGH & VGL voltage found all not output 0V only.

It was shows that their DC-DC section is not working. After analysis the ir DC-DC section, it is using the UP1 IC (AT1380A) as a DC-DC IC. The UP1 pin4, on/off switch is control by the T-CON main chipset U3 (CM2681A-KQ) pin 63.

Usually when the TV on, T-CON board IC U3 (CM2681A-KQ) pin63 (PWRON) will output a signal logic high (3.3V), through QP3 inverse the signal to logic low and reach to UP1 pin4. After that, UP1, DC-DC section starting working and generates VDA, VGH & VGL voltage outputs.
But for this T-con board, even the TV was power on, but their U3 (CM2681A-KQ) pin 63 still is logic low 0V. Normally this U3 pin 63 will follow by TV power on and off, their voltage range is between 0V~3.3V. Even disconnect the U3 pin63 with other corresponding components, this pin63 also not different still 0V. Suspect their U3 (CM2681A-KQ) damage, after replace U3 the TV was back to normal now.
Hisense TLM40V68PK LCD TV 
1) Pop up OSD Menu Randomly
2) Front panel buttons sometime no function

3) When TV in standby mode, can’t use the remote control to power on (start-up) the TV.
4) Auto power on of power off the LCD TV.
> All these symptoms were causing by the ESD protection component call it as MLV (Multi-Layer Varistor). It is look like a small SMD diode and its function as an ESD protection & surge noise. How to testing it? Yes, this type of components normally they are using much in main board. So you can use the diode range to compare their values. If one of that MLV values different much or shorted, then you can direct remove it and power on the TV. If the problem solved, then you can find another MLV from a junk mainboard to replace it.
No wonder what brands or models of your LCD TV, if you’re facing the above LCDTV symptom and haven’t find out what was wrong, then you can try to check these MLV components inside their corresponding circuit lines. Some time on the signal input line, it is not one MLV defective, but maybe 2 or 3 units. For example, I had repaired an LCD TV with VGA port signal input no display problem. After checking their signal R, G, B, SDA & SCL lines got 3 MLVs shorted. Normally one MLV will using in one signal line, but this LCD TV VGA input signal got 3 MLV of them shorted and affect the VGA mode no display symptom.
Hisense TLM-3233D LCD TV
No Display but Blue Screen with Two Vertical White Bars
> When power on this lcd tv, the screen show no display but blue screen with two vertical white bars. The two vertical white bars will flash but no any content inside. The LCD TV can hear the sound and remote control to change channel properly. Try other video signals input like AV and PC also same results. Even try to call out the OSD menu also same problem too.  Since the LCD TV cannot show the OSD menu and the TV got sound and change channel properly, so that the mainboard is normal. After observation this lcd tv, found that the problem could be in the T-CON board or LCD panel. Check LVDS and FPC cables, they are show as normal, then check the T-CON board voltages. All voltages in T-CON board are ok, so that i will suspect the T-CON board mainchip (N39) or their memory chip (N31) defective. I got the junk T-CON board with same part number, but their DC-DC chip was burnt. So the main chip and memory IC can be use. Because of the N39 (CM2681) have many pins and the memory IC N31 (24LC128) only have 8 pins, so that I choose to replace the N31 first. After replace the N31, I try to power on the TV, and it was show display perfectly.
Since this N31 is a memory IC, does that mean IC itself damage or just the firmware corrupt and caused this problem happen? To check it, I did use my programmer to copy the working memory IC firmware and write it into the new memory IC. Yes, the LCD TV working perfectly. The problem solved and it was causing by the firmware corrupted.
The T-CON board memory chip or their firmware corrupt also can cause the screen problem. So that we need to save their firmware and must prepare some junk boards of T-con board, main board and inverter board for future use.
Hisense TLM3201 LCD TV
No Display but sound and other function properly.
> This model of LCD has using two type of LCD panel. These LCD Panel are QD32HL01 and another one is QD32HL03.
For this LCD TV symptom, no display, the QD32HL01 LCD panel their T-CON board Q300 open circuit causing the TV no display. This Q300 function as an on/off switch for DC-DC section. Direct replace Q300 with FDN339AN and the problem solved.
For the LCD panel using QD32HL03, their T-CON board D304 (BAV99LT1) opened circuit and causing the TV no display. This D304 is using on the VGH circuit line. After replace D304 the TV problem solved.
Hisense TLM40V68P LCD TV (T-CON Board: V400H1-C01)
Display White Screen only.
The other function like sound and remote control are ok and working properly.
> This LCD TV panel take a bit long time to start-up the display. But the TV display white screen only. Since all other function normal, so the suspicion section is the T-con board.
Starts measuring this T-con board and found that their VGHP voltage is missing, 0V but other voltage testing points are normal. Normally this VGHP has about 19.5V. Power off the TV, using Multimeter ohm range to measure their VGHP point with GND and the values is 0 ohm! That’s mean the VGH P circuit line has component shorted. First check the circuit line filter caps, when remove that capacitor CP19, the VGHP circuit line ohm values are back to normal. After testing this CP19 and found it was shorted. After replace CP19 on the T-con board, the problem still remains the same! When checking the VGHP circuit line, it is still 0V. Forward to UP1 pin10, here can measure the 2.25V and 5VAC output. VAA testing point has about 13V, so to confirm that the DP5 is open circuit. After removed DP5 and using Multimeter to testing this component, double confirm that DP5 is opened circuit. After changed both components, the TV appear the display perfectly.
Hisense TLM4288 LCD TV
Screen fully of vertical color lines and then no display.
When power on the TV, it is ok but after half an hour, the screen was changed to vertical color lines. And it also appears some horizontal bar on the screen. Some time it can back to normal and change to vertical lines and then the TV no display. But their sound, backlight and the remote control, all function working properly.
> For this LCD TV symptom, so the suspicion parts will be the LVDS cable or their T-con board problem. This TV symptom was because of the mainboard LVDS signal are not match with timing control in the T-con board. First checking the LVDS cable both sides contact pins are clean and no any dirty on the pins. After that checking their cable continuity and it is ok. So the other part is the T-con board.
After testing T-con board all voltages normal and stable, so the problem should be in the LVDS connector and their signals processing section. Since this TV symptom was occur after half an hour, so it could be the components dry joints or heat sensitive. So after power on the TV, try to using a plastic rod to pressing the T-con. When the plastic rod pressing on the LVDS connector socket, the TV screen back to normal! So the culprit is the LVDS connector socket dry joints. After resolder the LVDS connector socket, the LCD TV is ok, even after burn test about 4 hours it’s still working properly.
Hisense LCD4204EU LCD TV
Dead after a Bang Noise.
> Replace chopper drive STRX6769, RE038 (10R) and RE032 (150R) in primary PSU.
Hisense TLM4788P LCD TV
Dead.
TV power on, testing the PSU secondary output voltage +12V, +5V_M & +24V all are = 0V no output. After that, testing the standby voltage +5V_S also same as 0V. That’s mean it was the standby voltage supply section malfunction.
Checking the NE521 (STR-A6351) pin 7 & 8 has 300V, but pin 3 is 0V.  Normally this Power IC Vcc pin has about 15V.
> Check the corresponding components on Vcc line and found that RE523 was open and other parts are normal. Replaced a new RE523 resistor, the TV is OK.

Samsung LCD TV service tips - 2/2

Samsung 32 Inches LCD TV
Symptom: Hissing or Hum noise of the SMPS in 32 inches LCD TV
There may be a sort of hissing noise in the SMPS for 32" LCD TV. The noise occurs when the set is in the stand by condition. The SMPS code is BN96- 03057A and defective SMPS version is the "REV 1.1".
> Replace the SMPS to new version (V1.2 or latest version).

Samsung 26, 32 & 37 Inches LCD TV Year 2009 Europe models
Symptom: No Power, No picture or no backlight.
Cause: DP805 Diode (MUR360).
> Change DP805 from MUR360 to 31GF6 diode on IP boards.
=> MUR360 risk range: 0907*/0908*/0909* marked on diode.
1. Change MUR360 Diode to 31GF6 Diode
2. Marking a dot on yellow box after changing this diode.
Samsung LNS4695DX/XAA, LNS4696DX/XAA,LNS4096DX/XAA, LNS4095DX/XAA LCD TV
Symptom: Poor or Intermittent Video.
> Check the LVDS cable where it connects to the panel interface board. Be sure that the cable does not have any glue on it. On occasion, the glue can cause a poor connection if it gets into the connector. Remove glue or replace the LVDS cable with BN39-00726A.

Samsung LN32A330J1DXZA, LN32A450C1DXZA,LN32A550P3FXZA, LN32A540P2DXZA, LN32A330J1NXZA,LN32A450C1HXZA, LN32A450C3HXZA,LN32A300J1DXZA LCD TV
Symptom: Standby light is on, flashes once briefly then unit attempts to turn on
> If the unit will not turn on, but the red standby LED is on and flashes once quickly when the power button is pressed on the remote or the TV, the 2200uf 10v filter capacitor on the SMPS has failed. This capacitor is located in the upper right side of the power supply close to the cable that connects the main board. Visual inspection will normally show that it has a swollen top. Replace capacitor and inspect the others in the filter stage to restore operation.

Samsung LNS4051DX/XAA LCD TV
Symptom: Dead backlight flashes on then off.
> Unit would flash on then off and audio would work. You could saw video with a flashlight. Sometimes unit would stay on and run if you cycled on and off many times. Found bad solder connection on IP board TI801 on primary side.
Re-soldered and problem solved.

Samsung LNT4065FX/XAA, LNT4665FX/XAA,
LNT5265FX/XAA, LNT4061FX/XAA, LNT4661FX/XAA LCD TV
Symptom: Half screen is purple colour.
> Half screen is purple color. That’s mean LCD panel controller board is defective. Panel needs to be replaced.

Samsung LN32C350D1DXZA LCD TV
Symptom: Multiple Vertical lines.
> Try to call out the OSD Menu, the multiple vertical lines that do not go through the OSD menu. If the symptom does not affect the OSD menu (as shown above) or does not appear in the test picture, replace the main board only. Do not replace the LVDS or T-Con board or the LCD Panel.

Samsung LN-52A850 LCD TV
Symptom: The image breaks up or doubles images on the right side of the screen.
> Replace T-CON board and problem solved.
Samsung LN46B530P7NXZA LCD TV
Symptom: There is color distortion on objects or people’s faces.
> The LVDS cable can cause this if it isn’t seated correctly. Check the position of the LVDS cable and the contacts. If it is seated correctly, replace the LVDS cable.

Samsung LNT4661FX/XAA LCD TV
Symptom: Half of the screen is black or purple on all inputs.
> When call out the OSD menu, the problem also affects the OSD menu, replace the LCD panel.

Samsung LNT5271FX LCD TV
Symptom: Left side of the screen is dark. The right side of the screen have horizontal lines with distorted video.
> The symptom also affects the OSD Menu, so replace the T-CON board then problem solved.

Samsung LNS4051DX/XAA LCD TV
Symptom: Clicking repeatedly TV will not turn on
> Found 2 electrolytic 100uf at 16v capacitors on the 5v line C115 and C123 bad.
Or replace the power supply.

Samsung LNS4051DX/XAA LCD TV
Symptom: Dead Backlight Flashes On then Off.
UNIT WOULD FLASH ON THEN OFF AND AUDIO WOULD WORK.  YOU COULD SEE VIDEO WITH A FLASHLIGHT. SOMETIMES UNIT WOULD STAY ON AND RUN IF YOU CYCLED ON AND OFF MANY TIMES. FOUND BAD SOLDER CONNECTION ON IP BOARD TI801 ON PRIMARY SIDE. RESOLDERED AND CORRECTED PROBLEM.

Samsung LNS4692DX/XAA LCD TV
Symptom: No video TV but has backlight and audio. TV will not come on.
> Found pico fuse open at cp1 on the T-CON PCB. If shorted CP1 with a wire jumper, TV comes on and runs fine. Replace the Pico fuse or T-CON PCB.

Samsung LNT3242HX/XAA, LNT3232HX/XAA LCD TV
Symptom: Can’t power on.
> TV would not come on. Removed the back and as soon as we did the set came on. Found glue was around cables on the SMPS. Cleaned glue off and cleaned the terminals. Set operates normally.

Samsung LNT3253HX/XAA LCD TV
Symptom: After a few minutes when TV warms-up picture becomes distorted
> 10-15 minutes after you turned on the unit panel warms-up and picture becomes distorted. If you just push the TV's frame picture becomes even more distorted.  On the back of the panel the CONTROL ASIC area is very hot. Replace the panel to fix the problem.

Samsung LNT4065FX/XAA, LNT4665FX/XAA,
LNT5265FX/XAA, LNT4061FX/XAA, LNT4661FX/XAA LCD TV
Symptom: Blue screen without signal. If provide with signal the blue screen
will flash white short horizontal lines.
> Refit or replace LVDS cable, check if the cable not strangled by the metal cover and loosen up the screws of the cover.
Samsung LNT4665FX/XAA LCD TV
Symptom: Brightness lost after replaced MAIN PCB.
> Because MAIN PCB BN94-01199E is designed to work with both models LNT4665FX/XAA and LNT4661FX/XAA when you replaced the board is possible to lost the brightness. Go in SERVICE MODE and turn value LVDS BYTE from 8 to 10.

Samsung LNT5271FX/XAA, LNT4671FX/XAA LCD TV
Symptom: TV is cycling, the red LED light blinking and the relay is cycling sometime TV will come on.
> TV is cycling, the red LED light blinking and the relay is cycling sometime TV will come on. Even the Main board replaced, did not fix. This was a used unit, found cable from the main board to the side AV jack was reversed, is not labeled as to direction of use. This cable if reversed will be hot to the touch.
Found by removing and re-plugging and changing direction of cable TV worked.
This was tried on both model numbers with the same result.

Samsung LN32B360C5DXZA,LN32B530P7FXZA,LN32B650T1FXZA,LN32B460B2DXZA,LN32B540P8DXZA,LN32B550K1FXZA,LN32B640R3FXZA,LN32B457C6HXZA,LN32B450C4HXZA,LN37B457C6HXZA,LN37B530P7FXZA,LN37B650T1FXZA,LN37B550K1FXZA,LN40B457C6HXZA,LN40B550K1HXZA,LN40B 500P3FXZA,LN40B550K1FXZA,LN40B650T1FXZA,LN40B530P7FXZA,LN40B530P7NXZA,LN40B750U1FXZA,LN40B 540P8FXZA,LN40B610A5FXZA,LN40B630N1FXZA,
LN40B640R3FXZA,LN46B650T1FXZA,LN46B530P7NXZA,LN46B530P7FXZA,LN46B550K1FXZA,LN46B610A5FXZA,LN46B540P8FXZA,LN46B630N1FXZA,LN46B640R3FXZA,LN46B 750U1FXZA,LN52B550K1HXZA,LN52B610A5FXZA,LN52B550K1FXZA,LN52B540P8FXZA,LN52B530P7FXZA,LN52B630N1FXZA,LN52B750U1FXZA,LN55B640R3FXZA,LN55B650T1FXZA LCD TV
Symptom: Firmware blinking in Red at the top of the screen
Problem - After changing the main board, I'm now stuck with the firmware blinking in RED print at the top of the screen.
> The unit is stuck in aging mode. To exit, simply hit the menu button on the TV itself.

Samsung LN32B360C5DXZA,LN32B530P7FXZA,LN32B460B2DXZA,LN32B540P8DXZA,LN32B550K1FXZA,LN37B530P7FXZA,LN37B550K1FXZA,LN40B550K1FXZA,LN40B530P7FXZA,LN40B 530P7NXZA,LN40B530P7FXZC,LN40B540P8FXZA,LN46B530P7NXZA,LN46B530P7FXZA,LN46B550K1FXZA,LN46B 540P8FXZA
Symptom: Flickering on the screen intermittently
When the unit is connected via HDMI to a Scientific Atlanta cable set top box set in by pass mode for resolutions 480p and 720p a flickering will occur.
> Change the cable box to a fixed resolution. OR have the customer install the latest TV firmware which can be located on samsung.com.

Samsung
LN46A550P3FXZA,LN46A650A1FXZA,LN46A530P1FXZA,LN46A750R1FXZA,LN46A860S2FXZA,LN46A950D1FXZA,LN46A540P2FXZA,LN46A850S1FXZA,LN46A630M1FXZA,LN46A 580P6FXZA,LN52A530P1FXZA,LN52A750R1FXZA,LN52A650A1FXZA,LN52A550P3FXZA,LN52A630M1FXZA,LN52A 860S2FXZA,LN52A850S1FXZA,LN52A540P2FXZA,
LN40A530P1FXZA,LN40A450C1DXZA,LN40A330J1DXZA,LN40A 550P3FXZA,LN40A650A1FXZA,LN40A630M1FXZA,LN40A540P2FXZA LCD TV
Symptom: Unit cycles on/off during start-up.
> If the unit tries to turn on but begins to cycle on and off before any video is displayed and all of the SMPS voltages are good, disconnect the LVDS cable at the T-Con board. If the set starts and the backlights come on, replace the T-Con board. If the set does not start, disconnect the LVDS cable at the main board. If the set starts, replace the LVDS cable. If the set still does not start-up, replace the main board.

Samsung
LN32A330J1DXZA,LN32A450C1DXZA,LN32A650A1FXZA,LN32A 550P3FXZA,LN32A540P2DXZA,LN32A330J1NXZA,LN32A300J1DXZA,LN40A530P1FXZA,LN40A450C1DXZA,LN40A750R1FXZA,LN40A 330J1D
XZA,LN40A550P3FXZA,LN40A540P2FXZA,LN40A500T1FXZA,LN46A530P1FXZA,LN46A860S2FXZA,LN46A750R1FXZA,LN46A 550P3F
XZA,LN46A650A1FXZA,LN46A950D1FXZA,LN46A540P2FXZA,LN46A500T1FXZA,LN46A850S1FXZA,LN46A630M1FXZA,LN46A 850S1F
XZX,LN46A580P6FXZA,LN52A530P1FXZA,LN52A750R1FXZA,LN52A650A1FXZA,LN52A550P3FXZA,LN52A630M1FXZA,LN52A 860S2F
XZA,LN52A850S1FXZA,LN52A540P2FXZA,LN52A580P6FXZA
Symptom: Auto-shutdown on 2008 LCD TV’s.
> Upon inspections of 2008 LCD TV's we have found that the LVDS (ribbon cable) can cause an auto shut down. Even if the LVDS cable doesn’t look defective try changing it anyway and retest the TV. It is a good practice to carry a few extra LVDS cables for such testing circumstances.

Samsung
LN32B360C5DXZA,LN32B530P7FXZA,LN32B650T1FXZA,LN32B 460B2DXZA,LN32B540P8DXZA,LN32B550K1FXZA,LN32B640R3FXZA,
LN32B457C6HXZA,LN32B450C4HXZA,LN32B540P8DUZA,LN32B 450C3HXZA,LN32B460B2DUZA,LN32B360C5DUZA,LN32B550K1FUZA,
LN32B530P7FUZA,LN32B450C3HUZA,LN40B530P7FUZA,LN40B 550K1FUZA,LN40B457C6HXZA,LN40B550K1HXZA,LN40B610A5FUZA,
LN40B640R3FUZA,LN40B650T1FUZA,LN40B630N1FUZA,LN40B 540P8FUZA,LN40B500P3FXZA,LN40B550K1FXZA,LN40B650T1FXZA,
LN40B530P7FXZA,LN40B530P7NXZA,LN40B750U1FXZA,LN40B 540P8FXZA,LN40B630N1FXZA,LN40B640R3FXZA,LN52B550K1HXZA,
LN52B610A5FXZA,LN52B550K1FXZA,LN52B540P8FXZA,LN52B 530P7FXZA,LN52B630N1FXZA, LN52B750U1FXZA LCD TV
Symptom: Backlight Failure Testing.
> Backlight failures can be partial or full failure check the backlight supply voltage (refer to service manual). If supply voltage is present, use a flashlight behind the television and shine a light through the panel. If the video is working you will see it.
Samsung
LNT4069FX/XAA,LNT4066FX/XAA,LNT4669FX/XAA,LNT3255HTX/XAA,LNT375HAX/XAA,LNT4042HX/XAA,LNT325HAX/XAA,LNT405HAX/X
AA,LNT2353HTX/XAA,LNT3753HX/XAA,LNT2653HTX/XAA,LNT3242HTX/XAA,LNT3253HTX/XAA,LNT4042HTX/XAA,LNT4053HTX/XAA,LNT
4071FX/XAA,LNT4671FX/XAA,LNT5271FX/XAA,LNT4642HX/XAA,LNT466FX/XAA,LNT4065FX/XAA,LNT4665FX/XAA,LNT5265FX/XAA,LNT26
32HX/XAA,LNT2642HX/XAA,LNT2653HX/XAA,LNT3232HX/XAA,LNT3242HX/XAA,LNT3253HX/XAA,LNT3732HX/XAA,LNT4032HX/XAA,LNT
4053HX/XAA,LNT4061FX/XAA,LNT4661FX/XAA LCD TV
Symptom: Intermittent LCD Video Troubleshooting.
> Troubleshooting intermittent video problems can be time consuming, but these tips may help narrow down the cause of an intermittent video problem.  The very first thing to do is to make sure the customer does not have OSD.  They can verify this by just pressing Menu or Volume on their TV remote control. If they do have OSD, then the problem is most likely in the source and not the TV.
The next step when encountering an intermittent video problem is to find out if the backlights are on when the set looses video. You can probably obtain this information from the customer before you schedule the call. Ask if they noticed if the screen is completely black or if it is lit up slightly when the video goes out.  They may be able to notice it better if they stand at an angle to the TV and turn it on or off and see if there is any change in brightness.  If the backlights are out, you need to know if the set ever has video when they
turn it on, or does it go out after they have had the set on for a period of time. If the set occasionally will not have backlights when it is first turned on, suspect the panel or power supply/IP board. If the set has video for a while and then looses the backlights, suspect a power supply/IP board or main board. Typically  the panel will cause a no backlight at turn on, while the power supply and Main Board will cause the backlights to go out after a period of time. If the set has backlights when first turned on and the lights change their brightness in several steps before quickly going out, suspect the IP board.  If the backlights are on when the set loses video after it has been on for a while, most likely the LVDS cable is defective. If the set has backlights but no video when it is first turned on, the T/Con or Main Board would probably be at fault.  Always check the simple things first, like a LVDS cable that is not plugged in properly or a power connector to the panel being loose.  There are exceptions to every rule, but this generally should help with narrowing down no video in LCD sets.

Samsung LN32A450C1DXZA, LN32A450C1HXZA,LN32A450C3HXZA, LN32A330J1DXZA, LN32A330J1NXZA LCD TV
Symptom: Video will intermittently turn mostly white.
White screen with a faint image of OSD and video is in the background. Video will intermittently turn mostly white with the OSD barely visible in the background. Even a black image or when the panel should not be showing any video, it is white. Found that one of the sub-boards inside the panel, the boards that the ribbon cable from the T-Con connect to, are not seated properly and the larger SMD capacitors on the board are intermittently making contact with the metal frame of the set, effectively creating a short to ground.
This is one of the panels that are mounted upside down, so the stand mounts just below and behind the panel frame. Any slight pressure from the stand can cause the frame to make contact. In many cases, the TV can be slightly flexed to make this issue occur.
Here, just beside a T-Con ribbon cable, you can see that the sub-board is not seated properly, and is in fact bowing towards the outer frame.

Samsung LNT4061FX/XAA, LN32A450C1DXZC,
LN32A550P3FXZC, LN32A550P3FXZX, LN32A450C1DXZX,LN32A650A1FXZA, LN32A450C1XZD, LN32A450C1DXZA,
LN32A540P2DXZA, LN32A450C1XZP, LN32A550P3RXZD,LN40A530P1FXZA, LN40A530P1FXZX, LN40A450C1HXZX,
LN40A450C1DXZA, LN40A750R1FXZA, LN40A450C1DXZX,LN40A530P1FXZC, LN40A550P3FXZC, LN40A650A1FXZC,
LN40A550P3FXZX, LN40A750R1FXZC, LN40A330J1DXZX,LN40A650A1FXZX, LN40A450C1XZD, LN40A450C1DXZC,
LN40A330J1DXZA, LN40A550P3FXZA, LN40A650A1FXZA,LN40A750R1FXZX, LN40A550P3RXZD, LN40A330J1XZD,
LN40A630M1FXZA, LN40A540P2FXZA, LN40A650A2RXZD,LN40A630M1FXZC, LN40A630M1FXZX, LN40A610A3RXZD,
LN40A500T1FXZA, LN40A330J1XZP, LN40A450C1XZP,LN40A650A1RXZP, LN40A610A1RXZD, LN40A650A1FXZD LCD TV
Symptom: Troubleshooting Inverter PCB boards
> The inverter PCB is the power supply for the Cold Cathode Fluorescent tubes.  The inverter acts exactly like the ballast used in a standard fluorescent light fixture. In the case of an LCD TV, 24 volts from the power supply is applied to a switch mode power supply (SMPS). The SMPS outputs ~1000 Volts to energize the bulbs then the voltage drops to ~ 500 volts for run operation. The SMPS switching frequency is around 90 KHz.
The first step for verifying inverter board operation is to confirm the 24 volt supply is present. An oscilloscope can also be used to verify the SMPS circuit is oscillating. Simply holding the oscilloscope probe in the area of the switching transformer will show screen activity if the switching action is taking place.  Measuring the SMPS output with standard equipment is not recommended as this is high voltage and at a high frequency.


Samsung LN40A650A1FXZA, LN46A650A1FXZA,LN40A750R1FXZC, LN46A750R1FXZA, LN40A750R1FXZA LCD TV
Symptom: Unit tries to start with melody but cycles off and back on.
> If the unit tries to turn on and makes the start-up melody but then immediately shuts off and starts again, unplug the LVDS cable and apply power again. If the set stays on, replace the T-Con board.
Model/s: Samsung LNT4071FX/XAA, LNT4671FX/XAA,LNT5271FX/XAA LCD TV
Symptom: Video Stuttering or Hesitation
> The customer may complain that the video has a stutter or hesitation when viewing regular program, either standard definition or high definition.
To fix, go into the customer menu, select Picture, then scroll to Auto Motion Plus 120Hz and select Off.  This enhancement circuit works for some movies, but can introduce severe hesitations and ghosting on regular programming. The customer should also be informed that this does not affect the 120Hz operation of the panel. The panel operates at 120Hz regardless of this setting.

Samsung LN52A650A1FXZA, LN40A650A1FXZA,LN46A650A1FXZA, LN52A650A1FXZC, LN46A650A1FXZC LCD TV
Symptom: Will not turn on, cycles on and off with start-up melody, no backlights
> If the set will try to turn on and the start-up melody sounds but no backlight appears and the set cycles off and on every 5 to 10 seconds, unplug the LVDS cable from the T-Con/FRC board. If the set then runs and the backlights come on and stay on, replace the defective T-Con/FRC board.

Samsung LNT4069FX/XAA,LNT4066FX/XAA,LNT4669FX/XAA,LNT4071FX/XAA,LNT4671FX/XAA,LNT5271FX/XAA,LNT4065FX/XAA,LNT4665FX/XAA,LNT5265FX/XAA,LNT4061FX/XAA,LNT4661FX/XAA
Symptom: Unit cycles on and off several times before starting.
> If the unit will cycle on and off several times before turning on and then playing fine, check the power supply carefully for filter capacitors with bulged tops. Replace the capacitors or power supply to correct the issue.

Samsung LN26B460B2DXZA; LN26B360C5DXZA; LN26B457C6HXZA; LN32B460B2DXZA; LN32B360C5DXZA; LN32B540P8DXZA; LN32B457C6HXZA;LN32B530P7FXZA;LN32B550K1FXZA; LN37B530P7FXZA; LN37B550K1FXZA;LN37B650T1FXZA
Symptom: No Backlight but sound ok.
TV will power up but have no backlight operation (No display). Sound is OK.
Procedure:
1. Verify that the TV is within the serial number range by checking the ninth digit in the serial number (i.e. AZ4D3CTS5 Ninth digit is a 5).
2. If the digit is 4 or 5, check the number on the diode itself to verify whether it has already been replaced.
3. If the diode has “0907”, “0908” or “0909” on its case (refer to photos 1 & 2), replace with new (Part number 0402-001415).
Verify the cause of the symptom by measuring (in circuit) across the diode (location DP805) (see photos 3 through 6). If the resistance measures between 500 and 600 ohms, the diode is good and therefore the symptom is being caused by a different reason. If the resistance measurement approaches zero ohms (shorted) the diode is defective and needs to be replaced using part number 0402-001415.
> There are two versions of the IP board with different physical layouts  using the same diode type. Replace the diode using standard soldering methods for a lead-free application. If the diode is not available, order the IP Board.

Samsung LCD TV – Service Tips - 1/2

Samsung LNT3253: After a few minutes when TV warms-up picture becomes distorted 
Samsung LNT3253HX/XAA LCD TV.
After a few minutes when TV warms-up picture becomes distorted
> 10-15 minutes after you turned on the unit panel warms-up and picture becomes distorted. If you just push the TV's frame picture becomes even more distorted. On the back of the panel the CONTROL ASIC area is very hot. Replace the panel to fix the problem.
Samsung: LN32A450_LN32A330: Video will intermittently turn mostly white
Samsung LN32A450C1DXZA,LN32A450C1HXZA,LN32A450C3HXZA,LN32A 330J1DXZA,LN32A330J1NXZA LCD TV
Video will intermittently turn mostly white
> White display with a faint image of OSD (On Screen Display) and video in the background. Video will intermittently turn mostly white with the OSD barely visible in the background. Even a black image or when the panel should not be showing any video, it is white. I found that one of the sub-boards inside the panel, the boards that the ribbon cable from the T-Con connect to, are not seated properly and the larger SMD capacitors on the board are intermittently making contact with the metal frame of the set, effectively creating a short to ground.
This is one of the panels that are mounted upside down, so the stand mounts just below and behind the panel frame. Any slight pressure from the stand can cause the frame to make contact. In many cases, the TV can be slightly flexed to make this issue occur.
You may see besides a T-Con ribbon cable that the sub-board is not seated properly, and is in fact bowing towards the outer frame.  Pulling the frame out slightly, you can see one of the SMD capacitors that can make connection with the frame.  Adding felt to the affected area will solve the issue.

Samsung most model: Firmware Blinking in Red at the Top of the Screen
Model/s: Samsung LN32B360C5DXZA,LN32B530P7FXZA,LN32B650T1FXZA,LN32B 460B2DXZA,LN32B540P8DXZA,LN32B550K1FXZA,LN32B640R3FXZA,LN32B457C6HXZA,LN32B450C4HXZA,LN37B 457C6HXZA,LN37B530P7FXZA,LN37B650T1FXZA,
LN37B550K1FXZA,LN40B457C6HXZA,LN40B550K1HXZA,LN40B500P3FXZA,LN40B550K1FXZA,LN40B650T1FXZA,LN40B530P7FXZA,LN40B530P7NXZA,LN40B750U1FXZA,LN40B 540P8FXZA,LN40B610A5FXZA,LN40B630N1FXZA,LN40B640R3FXZA,LN46B650T1FXZA,LN46B530P7NXZA,LN46B 530P7FXZA,LN46B550K1FXZA,LN46B610A5FXZA,
LN46B540P8FXZA,LN46B630N1FXZA,LN46B640R3FXZA,LN46B750U1FXZA,LN52B550K1HXZA,LN52B610A5FXZA,LN52B550K1FXZA,LN52B540P8FXZA,LN52B530P7FXZA,LN52B 630N1FXZA,LN52B750U1FXZA,LN55B640R3FXZA,LN55B650T1FXZA LCD TV.
Firmware blinking in Red at the top of the screen.
> Problem - After changing the main board, I'm now stuck with the firmware text info blinking in RED print at the top of the screen. The unit is stuck in aging mode. To exit, simply hit the menu button on the TV itself.
Samsung LNT4065_LNT5265: With Signal-Blue Screen and Flashing White Short Horizontal Lines
Model/s: LNT4065FX/XAA,LNT4665FX/XAA,LNT5265FX/XAA,LNT4061FX/XAA,LNT4661FX/XAA
Blue screen without signal, with signal -blue screen with flashing white short horizontal lines
> Refit or replace LVDS cable, check if the cable not strangled by the metal cover and loosen up the screws of the cover.

Samsung LNT3242_3232 : Wont Power On
Samsung LNT3242HX/XAA,LNT3232HX/XAA LCD TV
Symptom: Wont power on
TV would not come on. Removed the back and as soon as we did the set came on.
Found glue all on the cables to the smps. Cleaned glue off and cleaned the terminals. Set operates normally.
Samsung LN32A330: The TV takes longer to power on than normal
Samsung LN32A330J1DXZA,LN32A330J1NXZA LCD TV
The TV takes longer to power on than normal
The TV takes longer to power on than normal. You may hear several clicks while the TV attempts to power on.
The electrolytic in the capacitors on the power supply board over time will dry out causing the power supply to shut down during its initial power on cycle.
 
Samsung: Unit tries to start with melody but cycles off and back on
Samsung LN40A650A1FXZA,LN46A650A1FXZA,LN40A750R1FXZC,LN46A 750R1FXZA,LN40A750R1FXZA LCD TV
Unit tries to start with melody but cycles off and back on
> If the unit tries to turn on and makes the startup melody but then immediately shuts off and starts again, unplug the LVDS cable and apply power again. If the set stays on, replace the T-Con board.

Samsung: Will not turn on, cycles on and off with startup melody, no backlights
Samsung LN52A650A1FXZA,LN40A650A1FXZA,LN46A650A1FXZA,LN52A 650A1FXZC,LN46A650A1FXZC LCD TV
Will not turn on, cycles on and off with startup melody, no backlights
> If the set will try to turn on and the startup melody sounds but no backlight appears and the set cycles off and on every 5 to 10 seconds, unplug the LVDS cable from the T-Con/FRC board. If the set then runs and the backlights come on and stay on, replace the defective T-Con/FRC board.
Samsung LNS4692: No video TV, has backlight and audio. TV will not come on
Samsung LNS4692DX/XAA LCD TV
No video TV, has backlight and audio. TV will not come on.
> Found pico fuse open at cp1 on the T-CON PCB short cp1 TV comes on runs fine. Replace the T-CON PCB.

Samsung: Standby light is on, flashes once briefly then unit attempts to turn on
Samsung LN32A330J1DXZA,LN32A450C1DXZA,LN32A550P3FXZA,LN32A 540P2DXZA,LN32A330J1NXZA,LN32A450C1HXZA,LN32A450C3 HXZA, LN32A300J1DXZA LCD TV
Standby light is on, flashes once briefly then unit attempts to turn on
If the unit will not turn on, but the red standby LED is on and flashes once quickly when the power button is pressed on the remote or the TV, the 2200uf 10v filter capacitor on the SMPS has failed. This capacitor is located in the upper right side of the power supply close to the cable that connects the main board. Visual inspection will normally show that it has a swollen top. Replace capacitor and inspect the others in the filter stage to restore operation.
Samsung: Unit cycles on and off several times before starting
LNT4069FX/XAA,LNT4066FX/XAA,LNT4669FX/XAA,LNT4071FX/XAA,LNT4671FX/XAA,LNT5271FX/XAA,LNT4065FX/XAA,LNT4665FX/XAA,LNT5265FX/XAA,LNT4061FX/XAA,LNT4661FX/XAA
Unit cycles on and off several times before starting
> If the unit will cycle on and off several times before turning on and then playing fine, check the power supply carefully for filter capacitors with bulged tops. Replace the capacitors or power supply to correct the issue.
Samsung: Auto-shutdown on 2008 LCD TV’s 
Samsung LN32A330J1DXZA,LN32A450C1DXZA,LN32A650A1FXZA,LN32A 550P3FXZA,LN32A540P2DXZA,LN32A330J1NXZA,LN32A300J1 DXZA, LN40A530P1FXZA, LN40A450C1DXZA, LN40A750R1FXZA, LN40A330J1DXZA, LN40A550P3FXZA, LN40A540P2FXZA, LN40A500T1FXZA, LN46A530P1FXZA, LN46A860S2FXZA, LN46A750R1FXZA, LN46A550P3FXZA, LN46A650A1FXZA, LN46A950D1FXZA, LN46A540P2FXZA, LN46A500T1FXZA, LN46A850S1FXZA, LN46A630M1FXZA, LN46A850S1FXZX, LN46A580P6FXZA, LN52A530P1FXZA, LN52A750R1FXZA, LN52A650A1FXZA, LN52A550P3FXZA, LN52A630M1FXZA, LN52A860S2FXZA, LN52A850S1FXZA, LN52A540P2FXZA, LN52A580P6FXZA.
Auto-shutdown on 2008 LCD TV’s.
> Upon inspections of 2008 LCD TV's we have found that the LVDS (ribbon cable) can cause an auto shut down. Even if the LVDS cable doesn’t look defective try changing it anyway and retest the TV. It is a good practice to carry a few extra LVDS cables in your van for such testing circumstances.

Samsung: Unit tries to start with melody but cycles off and back on
Samsung LN40A650A1FXZA,LN46A650A1FXZA,LN40A750R1FXZC,LN46A 750R1FXZA,LN40A750R1FXZA LCD TV
Unit tries to start with melody but cycles off and back on.
> If the unit tries to turn on and makes the startup melody but then immediately shuts off and starts again, unplug the LVDS cable and apply power again. If the set stays on, replace the T-Con board.

Samsung LNS2651 & LNT3242: Picture is lost, sound OK after MAIN PCB was replaced
Samsung LNT3242HX/XAA, LNS2651DX/XAA LCD TV
Picture is lost, sound OK after MAIN PCB was replaced
> If after replacing MAIN PCB and made all correct setups in "OPTION BYTE" you get the symptoms:
* lost picture after 5-10 min. but sound OK, picture comes back if you restart the LCD but just to be lost again after the same interval or
* Picture is lost intermittently every 10-20 sec. and comes back itself, again sound OK.
You may not have to come back with another Main PCB, this may be corrected just by moving the connection between inverter and SMPS on the SMPS board. If it was on A-CNM803 move it to S-CNM802 or vice versa from S-CNM802 to A-CNM803 on the SMPS board, see picture. If this is not working then use a new MAIN PCB.
This may be applied to other LCD models too.

Samsung LNS4051: Clicking repeatedly TV will not turn on
Samsung LNS4051DX/XAA LCD TV
Clicking repeatedly TV will not turn on
> Found 2 electrolytic 100uf at 16v capacitors on the 5V line C115 and C123 bad. Or replace the power supply.

Samsung: Backlight Failure Testing
Model/s: Samsung LN32B360C5DXZA,LN32B530P7FXZA,LN32B650T1FXZA,LN32B 460B2DXZA,LN32B540P8DXZA,LN32B550K1FXZA,LN32B640R3 FXZA, LN32B457C6HXZA, LN32B450C4HXZA, LN32B540P8DUZA, LN32B450C3HXZA, LN32B460B2DUZA, LN32B360C5DUZA, LN32B550K1FUZA, LN32B530P7FUZA, LN32B450C3HUZA, LN40B530P7FUZA, LN40B550K1FUZA, LN40B457C6HXZA, LN40B550K1HXZA, LN40B610A5FUZA, LN40B640R3FUZA, LN40B650T1FUZA, LN40B630N1FUZA, LN40B540P8FUZA, LN40B500P3FXZA, LN40B550K1FXZA, LN40B650T1FXZA, LN40B530P7FXZA, LN40B530P7NXZA, LN40B750U1FXZA, LN40B540P8FXZA, LN40B630N1FXZA, LN40B640R3FXZA, LN52B550K1HXZA, LN52B610A5FXZA, LN52B550K1FXZA, LN52B540P8FXZA, LN52B530P7FXZA, LN52B630N1FXZA, LN52B750U1FXZA LCD TVs.
Backlight Failure Testing
> Backlight failures can be partial or full failure Check the backlight supply voltage (refer to service manual) If supply voltage is present, use a flashlight behind the television and shine a light through the panel. If the video is working you will see it.

Samsung LNS4041: Unit Continually Cycling On and Off
Samsung LNS4041DX/XAA LCD TV
Unit Continually Cycling On and Off. Set turns on and off in a continuous cycle. Plays the melody each time.
> First, check the power supply voltages, if missing, replace the power PCB. Next unplug the LVDS cable. If the set continues to cycle, replace the main PCB. If the cycling stops, replace the LCD panel. Part numbers are version dependent, so be sure to check the set's version.

Samsung LNT4671 & LNT5271: TV is cycling, the red led blinking and the relay is cycling
Samsung LNT5271FX/XAA,LNT4671FX/XAA LCD TV
TV is cycling, the red led blinking and the relay is cycling sometime TV will come on.
> TV is cycling, the red led blinking and the relay is cycling sometime TV will come on. The Main board replaced, did not fix. This unit was a Refurb, found cable from the main board to the side AV jack was reversed, is not labeled as to direction of use. This cable if reversed will be hot to the touch. Found by removing and replugging and changing direction of cable TV worked. This was tried on both model numbers with the same result.
Samsung: DEAD BACKLIGHT FLASHES ON THEN OFF
Model/s: Samsung LNS4051DX/XAA LCD TV
Symptom: Dead backlight flashes on then off.
UNIT WOULD FLASH ON THEN OFF AND AUDIO WOULD WORK. YOU COULD SEE VIDEO WITH A FLASHLIGHT. SOMETIMES UNIT WOULD STAY ON AND RUN IF YOU CYCLED ON AND OFF MANY TIMES. FOUND BAD SOLDER CONNECTION ON IP BOARD TI801 ON PRIMARY SIDE. RESOLDERED AND CORRECTED PROBLEM.

Samsung: Poor or Intermittent Video
Model/s: Samsung LNS4695DX/XAA,LNS4696DX/XAA,LNS4096DX/XAA,LNS4095DX/XAA LCD TV
Symptom: Poor or Intermittent Video
Cure/Solutions: Check the LVDS cable where it connects to the panel interface board. Be sure that the cable does not have any glue on it. On occasion, the glue can cause a poor connection if it gets into the connector. Remove glue or replace the LVDS cable with BN39-00726A.
Samsung: Half the screen is purple
Model/s: Samsung LNT4065FX/XAA,LNT4665FX/XAA,LNT5265FX/XAA,LNT4061FX/XAA,LNT4661FX/XAA LCD TV
Symptom: Half screen is purple
Cure/Solutions: Half screen is purple. LCD panel controller board is defective. Panel needs to be replaced.
Samsung: Video Stuttering or Hesitation
Model/s: Samsung LNT4071FX/XAA,LNT4671FX/XAA,LNT5271FX/XAA LCD TV
Symptom: Video Stuttering or Hesitation
Cure/Solutions: The customer may complain that the video has a stutter or hesitation when viewing regular programming, either standard definition or high definition.
To fix, go into the customer menu, select Picture, then scroll to Auto Motion Plus 120Hz and select Off.
This enhancement circuit works for some movies, but can introduce severe hesitations and ghosting on regular programming. The customer should also be informed that this does not affect the 120Hz operation of the panel. The panel operates at 120Hz regardless of this setting.

Samsung: Troubleshooting Inverter PCB boards
Model/s: Samsung LNT4061FX/XAA, LN32A450C1DXZC, LN32A550P3FXZC, LN32A550P3FXZX, LN32A450C1DXZX,
LN32A650A1FXZA, LN32A450C1XZD, LN32A450C1DXZA, LN32A540P2DXZA, LN32A450C1XZP, LN32A550P3RXZD, LN40A530P1FXZA, LN40A530P1FXZX, LN40A450C1HXZX, LN40A450C1DXZA, N40A750R1FXZA, LN40A450C1DXZX, LN40A530P1FXZC, LN40A550P3FXZC, LN40A650A1FXZC, LN40A550P3FXZX, LN40A750R1FXZC, LN40A330J1DXZX, LN40A650A1FXZX, LN40A450C1XZD, N40A450C1DXZC, LN40A330J1DXZA, LN40A550P3FXZA, LN40A650A1FXZA, LN40A750R1FXZX, LN40A550P3RXZD, LN40A330J1XZD, LN40A630M1FXZA, LN40A540P2FXZA, LN40A650A2RXZD,
LN40A630M1FXZC, LN40A630M1FXZX, LN40A610A3RXZD, LN40A500T1FXZA, LN40A330J1XZP, LN40A450C1XZP, LN40A650A1RXZP, LN40A610A1RXZD, LN40A650A1FXZD LCD TVs.
Troubleshooting Inverter PCB boards
The inverter PCB is the power supply for the Cold Cathode Fluorescent tubes. The inverter acts exactly like the ballast used in a standard fluorescent light fixture. In the case of an LCD TV, 24 volts from the power supply is applied to a switch mode power supply (SMPS). The SMPS outputs ~1000 Volts to energize the bulbs then the voltage drops to ~ 500 volts for run operation. The SMPS switching frequency is around 90 KHz. The first step for verifying inverter board operation is to confirm the 24 volt supply is present. An oscilloscope can also be used to verify the SMPS circuit is oscillating. Simply holding the oscilloscope probe in the area of the switching transformer will show screen activity if the switching action is taking place. Measuring the SMPS output with standard equipment is not recommended as this is high voltage and at a high frequency.
Samsung: Intermittent LCD Video Troubleshooting
Model/s: Samsung LNT4069FX/XAA, LNT4066FX/XAA, LNT4669FX/XAA, LNT3255HTX/XAA, LNT375HAX/XAA, LNT4042HX/XAA, LNT325HAX/XAA, LNT405HAX/XAA, LNT2353HTX/XAA, LNT3753HX/XAA, LNT2653HTX/XAA, LNT3242HTX/XAA, LNT3253HTX/XAA, LNT4042HTX/XAA, LNT4053HTX/XAA, LNT4071FX/XAA, LNT4671FX/XAA, LNT5271FX/XAA, LNT4642HX/XAA, LNT466FX/XAA, LNT4065FX/XAA, LNT4665FX/XAA, LNT5265FX/XAA, LNT2632HX/XAA, LNT2642HX/XAA, LNT2653HX/XAA, LNT3232HX/XAA, LNT3242HX/XAA, LNT3253HX/XAA, LNT3732HX/XAA, LNT4032HX/XAA, LNT4053HX/XAA, LNT4061FX/XAA, LNT4661FX/XAA LCD TVs.
Symptom: Intermittent LCD Video Troubleshooting
Troubleshooting intermittent video problems can be time consuming, but these tips may help narrow down the cause of an intermittent video problem.
The very first thing to do is to make sure the customer does not have OSD. They can verify this by just pressing Menu or Volume on their TV remote control. If they do have OSD, then the problem is most likely in the source and not the TV.
The next step when encountering an intermittent video problem is to find out if the backlights are on when the set loses video. You can probably obtain this information from the customer before you schedule the call. Ask if they noticed if the screen is completely black or if it is lit up slightly when the video goes out. They may be able to notice it better if they stand at an angle to the TV and turn it on or off and see if there is any change in brightness.
If the backlights are out, you need to know if the set ever has video when they turn it on, or does it go out after they have had the set on for a period of time. If the set occasionally will not have backlights when it is first turned on, suspect the panel or power supply/IP board. If the set has video for a while and then loses the backlights, suspect a power supply/IP board or main board. Typically the panel will cause a no backlight at turn on, while the power supply and Main Board will cause the backlights to go out after a period of time. If the set has backlights when first turned on and the lights change their brightness in several steps before quickly going out, suspect the IP board.
If the backlights are on when the set loses video after it has been on for a while, most likely the LVDS cable is defective. If the set has backlights but no video when it is first turned on, the T/Con or Main Board would probably be at fault.
Always check the simple things first, like a LVDS cable that is not plugged in properly or a power connector to the panel being loose.
There are exceptions to every rule, but this generally should help with narrowing down no video in LCD sets.
Samsung LE40R76B LCD TV
Symptom: Some vertical lines on the TV screen. But sound is ok.
> Check the PSU output voltages all ok. After that checking their T-con board Vcc input and Voltage regulator IC. Found that 2.5V Voltage Regulator IC no output. After replaced it the TV screen is ok.
Samsung UNxxC9000 LED TV
Symptom: The UNxxC9000 LED TV power up sequence
This power up sequence can help you troubleshoot the UNxxC9000, here is the power up:
a. When the AC cord is plugged in, the voltage on the STBY pin goes to 5.3V.
b. The MCU (Microcontroller, Micon &etc) on the mainboard actively looks for the user to press Power On switch from remote control or the TV itself.
c. When a user presses Power, the MCU sends a “High” voltage (0-1.2V transition) to the SMPS/PSU via Power_On/Off pin to activate the rest of the voltages.
d. After the 0-1.2V transition on the POWER_On/Off pin, the following voltages are activated on CNM801 and the “Melody” plays.
- Vamp= 18VDC
- OD_On/Off= 3.3V
- D5.3V = 5V
- D12V = 13V
e) Approximately two seconds later, 5V is applied to the BLU_On/Off pin.
f) Once the BLU_On/Off pin is activated, the LED arrays turn on. CNL801 supplies high voltage to the LED arrays. The following voltages are activated on CNL801 (with respect to chassis GND):
- BOT1+ = 170VDC
- BOT1- = 45VDC
- TOP1- = 45VDC
- TOP1+ = 170VDC
- TOP2+ = 170VDC
- TOP2- = 45VDC
- BOT2- = 45VDC
- BOT2+ = 170VDC
g) High voltage is applied to the panel LED arrays though connectors CN401 and CN402: Pin 1 and 12
-Approximately 170VDC (when referenced to the chassis GND).
-Voltage varies when referenced to connector GND.
Pin 6 and 7
-GND (effective).
-Approximately 45VDC when the backlight is lowest.
-GND Pins
-GND Potential is highest when signal is >90% duty cycle (almost DC).
-GND Potential is lowest when signal is <10% duty cycle (almost GND).
-Level is controlled by the mainboard though the Bot_Dim and Top_Dim pins on connector CNM801
Model: Samsung LN19C350DXZA LCD TV
Symptom: Display is completely Green color only.
> LVDS cable not properly inserted or dirty in the contact pins. Clean the LVDS cable contact pins and connect it back properly.
Samsung UN46C6300SF LED TV
Symptom: No Power
> This ICB801 (ICE3BR1765J) Power IC is defective on the PSU board.
Samsung LA32R91B LCD TV
Symptom: TV brightness and contrast features automatically change to 100% (maximum).
Even using the remote control adjusts it to 50%, but in a short time it will automatically change to 100% of brightness and contrast.
> Found some bulged electrolytic capacitors on the line of DC supply to mainboard. After replaced these electrolytic caps, the symptom was getting better but not completely. Even disconnect the front control panel and checking their circuit line till mainboard also normal. It is no any leakage ceramic caps in that circuit line. So it will suspect the flash memory, eeprom IC or the MCU. So starting from the easy way first, checking the eeprom IC. This eeprom IC is beneath of the mainboard and it is using 24C256BN (SMD SOP-8, 8 pins IC). Yes, this eeprom IC (AT24C256C) can be as a replacement for 24C256BN. After replaced a new blank EEPROM IC, the V problem solved.
Samsung LE27T51B LCD TV
Symptom: Dark frame with color stripes.
> Its looks like the unstable voltage problem. Check and replace UP4 (L1117DG) on T-CON board.

Samsung LE32R73BD LCD TV
Symptom: No picture and no OSD menu. Backlight OK.
> Reflow LVDS socket on screen driver PCB and mainboard PCB.

Samsung LE32R74BD LCD TV
Symptom: TV dead. Pulsating noise came from PSU and LED light flashes.
> Check schottky diode DM854 (MBRF1545CT) in PSU for short circuit.

Samsung LN32A330J1DXZA, LN32A330J1NXZA LCD TV
Symptom: The TV takes longer to power on than normal.
The TV takes longer to power on than normal. You may hear several clicks while the TV attempts to power on.
Cause: The electrolytic in the capacitors on the power supply board over time will dry out causing the power supply to shut down during its initial power on cycle.

Samsung LN40A650A1FXZA, LN46A650A1FXZA,
LN40A750R1FXZC, LN46A750R1FXZA, LN40A750R1FXZA LCD TV
Symptom: Unit tries to start with melody but cycles off and back on.
> If the unit tries to turn on and makes the start-up melody but then immediately shuts off and starts again, unplug the LVDS cable and apply power again. If the set stays on, replace the T-Con board.

Samsung LNT3242HX/XAA, LNS2651DX/XAA LCD TV
Symptom: Picture is lost; sound OK after MAIN PCB was replaced
> If you get the symptoms after replacing MAIN PCB and made all correct setups in "OPTION BYTE":
- Lost picture after 5-10 minutes but sound OK, picture comes back if you restart the TV but just to be lost again after the same interval or - Picture is lost intermittently every 10-20 sec. and comes back itself, again sound OK.
You may not have to come back with another Main PCB, this may be corrected just by moving the connection between inverter and SMPS on the SMPS board. If it was on A-CNM803 move it to S-CNM802 or vice versa from S-CNM802 to A-CNM803 on the SMPS board. If this is not working then use a new MAIN PCB. This may be applied to other LCD models too.

Samsung LNS4041DX/XAA LCD TV
Symptom: Unit Continually Cycling On and Off. Set turns on and off in a continuous cycle. Play the melody each time.
Repair/Solutions: First, check the power supply voltages, if missing, replace the power PCB. Next unplug the LVDS cable. If the set continues to cycle, replace the main PCB. If the cycling stops, replace the LCD panel. Part numbers are version dependent, so be sure to check the set's version.
Samsung LE32R73BD: No picture and NO OSD menu. Backlight OK.
Symptom: No picture and no OSD menu. Backlight OK.
> Reflow LVDS socket on screen driver PCB and main board PCB.
SAMSUNG LE32R74BD: TV dead.
Symptom: TV dead. Pulsating noise from PSU and LED light flashes.
> Check the shottky diode DM854 (MBRF1545CT) in PSU for short circuit.
Samsung LE27T51B: Dark frame with color stripes
Samsung LE27T51B LCD TV
Dark frame with color stripes.
> Unstable voltage problem. Check and replace UP4 (L1117DG) on T-CON board.

Samsung LN40A650_A750_LN46A750: Unit tries to start with melody but cycles off and back on Samsung LN40A650A1FXZA,LN46A650A1FXZA,LN40A750R1FXZC,LN46A 750R1FXZA,LN40A750R1FXZA LCD TV
Unit tries to start with melody but cycles off and back on
> If the unit tries to turn on and makes the startup melody but then immediately shuts off and starts again, unplug the LVDS cable and apply power again. If the set stays on, replace the T-Con board.

Samsung LNT4665FX/XAA lost brightness when you replaced MAIN PCB Samsung LNT4665FX/XAA LCD TV
LNT4665FX/XAA lost brightness when you replaced MAIN PCB
> Because MAIN PCB BN94-01199E is designed to work with both models LNT4665FX/XAA and LNT4661FX/XAA when you replaced the board is possible to lose the brightness. Go in SERVICE MODE and turn value LVDS BYTE from 8 to 10.

Samsung LNS4051: Dead Backlight Flashes On Then Off Samsung LNS4051DX/XAA LCD TV
DEAD BACKLIGHT FLASHES ON THEN OFF
UNIT WOULD FLASH ON THEN OFF AND AUDIO WOULD WORK. YOU COULD SEE VIDEO WITH A FLASHLIGHT. SOMETIMES UNIT WOULD STAY ON AND RUN IF YOU CYCLED ON AND OFF MANY TIMES. FOUND BAD SOLDER CONNECTION ON IP BOARD TI801 ON PRIMARY SIDE. RESOLDERED AND CORRECTED PROBLEM.
Samsung most models: Flickering on the screen intermittently
Model/s: Samsung
LN32B360C5DXZA,LN32B530P7FXZA,LN32B460B2DXZA,LN32B 540P8DXZA,LN32B550K1FXZA,LN37B530P7FXZA,LN37B550K1FXZA,LN40B550K1FXZA,LN40B530P7FXZA,LN40B 530P7NXZA,LN40B530P7FXZC,LN40B540P8FXZA,
LN46B530P7NXZA,LN46B530P7FXZA,LN46B550K1FXZA,LN46B 540P8FXZA.Symptom: Flickering on the screen intermittently
When the unit is connected via HDMI to a Scientific Atlanta cable set top box set in by pass mode for resolutions 480p and 720p a flickering will occur.
> Change the cable box to a fixed resolution. OR Have the customer install the latest TV firmware which can be located on samsung.com.

Samsung most models: Unit cycles on/off during startup
Model/s: Samsung LN46A550P3FXZA,LN46A650A1FXZA,LN46A530P1FXZA,LN46A 750R1FXZA,LN46A860S2FXZA,LN46A950D1FXZA,LN46A540P2FXZA,LN46A850S1FXZA,LN46A630M1FXZA,LN46A 580P6FXZA,LN52A530P1FXZA,LN52A750R1FXZA,
LN52A650A1FXZA,LN52A550P3FXZA,LN52A630M1FXZA,LN52A860S2FXZA,LN52A850S1FXZA,LN52A540P2FXZA,LN40A530P1FXZA,LN40A450C1DXZA,LN40A330J1DXZA,LN40A 550P3FXZA,LN40A650A1FXZA,LN40A630M1FXZA,LN40A540P2FXZA LCD TV.
Unit cycles on/off during startup
> If the unit tries to turn on but begins to cycle on and off before any video is displayed and all of the SMPS voltages are good, disconnect the LVDS cable at the T-Con board. If the set starts and the backlights come on, replace the T-Con board. If the set does not start, disconnect the LVDS cable at the main board. If the set starts, replace the LVDS cable. If the set still does not startup, replace the main board.