Sunday, May 22, 2016

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.