Question about Televison & Video

1 Answer

Part number for the samsung le52m87bd backlight inverter

I have a problem with the LE52m87 which I am told byy one of your experts is the backlight inverter (buzzing noise, no picture, but sound; shine a torch and can just see an image).

I have been given part number BN94-00963B which appears to be the control board. Do i replace this whole board (around $250) or is the backlight inverter separate/a part of this board? If so what part number is the backlight inverter? Generally they seem to be about $30 but i cant find the one for my set

many thanks

Posted by on

  • dlac Oct 06, 2008

    to clarify - i have been recommended the part number BN94-00963B not 'given one'



    thanks

  • dlac Oct 06, 2008

    having done further research should i not b replacing this : BN44-00150A instead of ordeing a BN94?

×

Ad

1 Answer

  • Level 1:

    An expert who has achieved level 1.

  • Contributor
  • 1 Answer

Hey!

I also have a SAMSUNG LE52M87 LCD TV and I have the same
ANOYING BUZZ comming from ( I think ) backlight converter. - I am
almost 100% that its because of the backlight inverter while the sound shifts frequency when backlight is changed ( from 1 - 10 ), but the volume of the buzz stays the same. Only the tone changes. I have this TV for a year now and havent realy noticed until now, so I think it started buzzing recently, because I didnt hear it before ( and I got realy sensitive hearing :) ) ...

ITS DRIVING ME CRAZY ...

PLEASE post what happened when ( if ) you changed the inverter,
or what did you do to solve the problem ...

Many thanks in advance!

Eddie from Slovenia

my email: Ldesign.marketing@gmail.com


Posted on Jan 08, 2010

Ad

1 Suggested Answer

6ya6ya
  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

Hi,
a 6ya Technician can help you resolve that issue over the phone in a minute or two.
Best thing about this new service is that you are never placed on hold and get to talk to real repair professionals here in the US.
click here to Talk to a Technician (only for users in the US for now) and get all the help you need.
Goodluck!

Posted on Jan 02, 2017

Ad

Add Your Answer

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

1 Answer

How do you fix a Samsung 55" Television with no picture but good sound?


The symptoms you described would indicate the backlights are not working.

The 2 main reasons are the backlight inverter board has gone or the backlights have blown!

Since you have replaced the inverter board with a new working one then this would point towards the LED backlights.

Apr 02, 2016 | Samsung Televison & Video

Tip

I have an RCA l32hd35d when you turn it on the tv comes on After about 2 seconds...


This is the basic guide that can be applied to most LCD flat panel TV.
By Bud Martin
First, try unplugging it from the outlet for about an hour to see if the TV will reset itself since the minute the TV is plugged into the wall, the power supply and processor will be running 24/7 and the EPROM can get corrupted by spikes and surges. Try using good quality surge suppressor to see if it will help if it happen often.
Look for burnt brown hot spots on the circuit boards, capacitors with leaking/bulging top or seals. Loose wires and connectors. Blown fuses.
Notes: We are dealing with high voltage that can kill you! so if you are not sure what you are doing, please have it fixed by the pro that has proper tools and safety equipment. Try to use GFI outlet and isolation transformer when work around the TV set and DO NOT DEFEAT THE GROUND PIN OF THE OUTLET/POWER CORD.

1) The power supply module (There are 4 regulated output voltages:- Standby 5vdc, switched 5vdc, 12~16vdc, and 24vdc).

The power supply converts the 120/230vac 50/60Hz into DC, then the high frequency (50~100kHz) switching circuits convert it back to AC but at high frequency which allows the power supply to use smaller and much lighter weight transformers (Ferrite core instead of heavy iron core), then this high frequency AC voltage is fed to the rectifier Diodes to get the DC output and filtered by DC filter capacitors that must have low ESR (Equivalent Series Resistance), if general purpose electrolytic caps are use, they will fail within a year or less due to high ESR.

The power supply has Standby 5vdc (5VSB, this is a MUST have before anything else will work, when this voltage is not present, there will be no any indicator light on the front panel) which is always on the minute the TV is plugged into the AC outlet, so it is on 24/7 and that is why the power supply will fail even though you may use the a TV not very often. It will see all the voltage spikes and surges 24/7.
This 5vdc is used to power the Processor and the Infrared remote receiver module which will be waiting for the command from the remote control or from the power switch, when the Power on command is received, the Processor will send the turn on signal (3.3~5vdc) to the power supply module (PSON pin) to the switch on the main 5vdc for the rest of the logic and Tuner circuits, 12~16vdc for the sound amplifiers (mostly Class D amplifier for efficiency and small size) and for the T-CON board (interface board between the LCD panel, some T-CON uses 5vdc, and the Logic board), and 24vdc for the Back lights inverter board (if there is no 24vdc then no back light).
Common failures:
Blown main AC fuse due to shorted out Diodes, transistors.
Bad capacitors leaking or bulging tops:
Shorted Diodes, transistors in the DC output side.

Testing the power supply output with dummy load:
24vdc testing: Disconnect the wires that go to the inverter board first. You can use two #1157 (using both Lo & Hi filaments by paralleling them at the base) car light bulbs connected in series so they can handle the 24vdc, this will put light load (about 70w) on the 24vdc output, the voltage out should be steady at 24vdc (+/-2v), if not, the power supply has regulation problem.
12vdc testing: disconnect the 12vdc TV load from the power supply board and attach one #1157 (using just the Hi filament), the 12vdc output should stay at 12v (+/-1v), if not, the power supply has regulation problem.

You should see the lamps go on when the TV power switch is ON and go OFF when the TV is powered OFF.

2) Main Logic board (It has Processor, Tuner, Sound Processor, Sources selector, Power amplifiers for speakers, interface port to the T-CON board for pictures).
This logic board sends out the turn on signals (3.3~5vdc) to turn on the rest of the Power supply module (Switched main 5vdc, 12~16vdc, and 24vdc), Inverter backlight ON (if no back light on command then there is no back lights),
Logic board supplies 5 or 12vdc to T-CON board B+ pin through switched transistor if T-CON board does not get the voltage from the logic board, you will get white/gray glowing screen without pictures.
Back lights Dimming (PWM) control signal.

3) Back lights Inverter board. Its job is to provide the drive voltage for the CCFL (Cold Cathode Fluorescent Lamp) to give white light for the screen.
This board is fed by the switched 24vdc (VBL) from the power supply module, it also get the Back lights on (BL on) control signal and the Dimming (Dim/PWM/) signal from the logic board. So for it to work, it needs 24vdc and the BL_ON signal.
Common failures:
Blown surface mounted fuses due to shorted transistors/ICs, Transformers.
Bad capacitors.

4) The T-CON (Timing Control or LCD controller) board (on the LCD panel assembly). It transfer the universal image signal of TTL and LVDS signal to specific TFT (Thin Film Transistor) LCD.
This is the interface board that talks to the Logic board and the LCD panel to produce pictures on the screen. White/gray glowing screen when it fails or not getting the voltage from the logic board (the 5 or 12vdc is supplied by switched transistor on the logic board). Notes: T-CON board is mounted under the metal cover shield.
Common failures:
Scrambled pictures, Lines, multiple pictures, color smears/blotches, rolling pictures after warm up.
Blown surface mounted fuse.
No pictures, very dark screen almost like there is no backlights.

5) LCD panel assembly to display pictures. The LCD pixels will block or unblock the back lights from the back of the panel to the front of the panel. This is the most expensive part of the TV, it will be more than the TV is worth.

As you can see, you must have all the above Voltages and signals for the TV to work properly. This may help you narrowing down the bad modules instead of buying the wrong module just to find out later that it did not solve the problem. Hope this will help you out.

Sound problem:
Let verify first to narrow down to where the problem can be. First, check the on screen sound set up menu to make sure the speakers are not set to OFF. If the setting is OK, then attach the powered PC speakers to the Audio Line out RCA jacks to see if you can get the sound there, if you do, then the problem can be in the power amp circuits, if you do not get the sound at RCA jacks, then the problem can be in the sound processor circuit. To get the sound repair, it can be from $150 and up, so if you can put up with using the good set of Powered PC speakers which actually give better sound than the tiny speakers inside the TV, I would keep using it that way, you may want to find out if the on screen sound setup will allow you to set the audio line out to be VARIABLE which means the sound output feeding the PC speakers can be varied using the TV remote control, then all you have to do is to set the PC volume to about half way up and set the TV volume to what ever you want.

Inverter board connector: you can also see the Fuse 4A/160V
http://i.fixya.nethttp://i.fixya.net13ca788.jpg
Power supply connector:
http://i.fixya.nethttp://i.fixya.net78e0d9a.jpg

http://i.fixya.nethttp://i.fixya.net2fc510f.jpg
T-CON board: (metal cover shielding is removed to show the bd.)
http://i.fixya.nethttp://i.fixya.net0b5367e.jpg
Inverter board:
http://i.fixya.nethttp://i.fixya.netaf0a695.jpg
Logic board:
http://i.fixya.nethttp://i.fixya.net4bd108e.jpg
T-CON board is dead, no power or blown fuse on the board, screen turns WHITE, must see it in darkened room, otherwise you may mistaken it for failed backlight.
http://i.fixya.nethttp://i.fixya.net3a91b68.jpg
Bad T-CON board after warm up, you get lines, multiple pictures, strange colors blotches, etc.
http://i.fixya.nethttp://i.fixya.netd3cf194.jpg
Bad caps (leaking/bulging tops). Make sure to replace bad cap with good cap such as PANASONIC FM or FC series , they are Low ESR (Equivalent Series Resistance) which is a must for switch mode power supply, and 105c rating. Do not use generic electrolytic caps.
http://en.wikipedia.org/wiki/Capacitor_plague

http://i.fixya.nethttp://i.fixya.netbe827ec.jpg
Bad T-CON board or power supply problem

http://i.fixya.nethttp://i.fixya.net034e1db.jpg

24vdc power supply output testing using two 12vdc car lamps in series.

http://i.fixya.nethttp://i.fixya.net4f2929c.jpg
Bad LCD panel, vertical 1~2 pixel wide lines
http://i.fixya.nethttp://i.fixya.net28e50c1.jpg
Failed TV and Monitors: http://s807.photobucket.com/albums/yy352/budm

Free service manuals: www.elektrotanya.com

on Mar 03, 2011 | Sony BRAVIA KDL-40S2010 40 in. LCD...

1 Answer

How do i fix sound but no picture on my samsung tv


Hi,
Your tv has problem with the back light inverter. As you didn't specified the model number its not possible to know is it back light or CCFL one. How ever i have added video to know hoe to find the inverter check it.

Samsung TV Repair Part Number Identification Backlight Inverters LED...
www.electro-medical.blogspot.com

Sep 10, 2015 | Samsung Televison & Video

1 Answer

Powers on, no display


Do you have sound? If so, dim the lights in the room and shine a bright flashlight on the screen and see if you have a faint picture. If you have a faint picture, you have a backlight problem. On most of those sets, the backlight inverter is combined with the power supply so that power supply/inverter board will more than likely be the culprit!

Dec 07, 2013 | Vizio E420VA 42 in. LCD HDTV

1 Answer

Backlight Inverter Repalced still not working


dim the lights in the room, turn on the set, and shine a bright flash light on the screen. Do you see a faint picture? Also be advised that there are a lot of bad parts floating around on EBay. No backlight condition could be cause by a bad main board, power supply, inverter board, high voltage short on the inverter output, or a bad backlight bulb.

Nov 07, 2013 | Toshiba Regza 42RV535U 42 in. LCD HDTV

1 Answer

How to fix backlight inverter


the inverter is right under the benzel, be carful

Feb 04, 2013 | Samsung 2494hm refurb 24in lcd 1080p...

2 Answers

DELL INSPIRON 1520 backlight or bulb


do you need bell laptop components?

Pcpartsltd.com limited is a direct Exporter of high quality notebooks, laptop power adapters, acer laptop batteries , laptop keyboards, laptop Inverters, laptop Hinges, laptop CPU Fan, laptop driver, laptop MotherBoards, Samsung Wall Mount, laptop LCD Bezel/ LCD lid, laptop lcd/led panel and Laptop LCD Video Cable. We are Laptop Parts experts.

Apr 27, 2012 | ASUS K50IJ-C1 Notebook

1 Answer

My acer monitor displays the acer background, makes a noise like a buzzing sound and goes black, and then after all my settings and background picture and information are complete and up, the monitar...


It sounds like a backlight or inverter problem. You can verify this by using a bright light to shine on the screen surface. If you can see the picture (but it will be very dark) that means that the backlight which illuminates the screen from behind. You would have to replace the inverter to test it, but there is good news: These are pretty difficult to find parts for, and not an easy repair for an amateur; acer products usually have a 3 year warranty on the backlight/inverter system, so I would start there.

May 25, 2011 | Acer V193W 19 inch LCD Monitor

1 Answer

I have a 1 yr old samsung flat tv that has a sound but no picture..how can i fix it. i am in an isolated island here in basco, batanes philippines with no experts in repairing flat tv.pls advice. tnx


Hi,
Kung LCD TV ang unit mo, 3 ang dahilan kung kaya la kang picture.
1. Me pundido kang backlight - kapag me pundido kang backlight kusang pinapatay ng power supply ang inverter board para hindi ma-overload kaya la kang picture. Maaring mong i-check ang backlight, ang palatandaan na ito ay pundido ay kapag me itim sa magkabilang dulo.
2. Sira ang inverter board - ang inverter board ang nagbibigay ng high voltage sa backlight. Kapag sira ito, natural d gagana ang backlight. karamihang sira ng backlight ay ang high voltage transformer, driver transistor o kaya me open na fuse/fusible resistor.
3. Power supply- kapag la supply voltage sa inverter board, la ka rin picture. Mas maganda kung ito ang sira dahil mas madali makhanap ng pyesa dyan sa lugar mo di katulad ng 2 nauna.
Kung me kakilala kang technician dyan malapit sa lugar nyo, patingnan mo yong mga sinabi ko. Maari ring dahil sa loose connection kaya la ka picture o kaya bad solder joints.
Salamat kapatid sa pagboto 4 na hinlalaki.
Jdvillanueva
Las Pinas NCR.

May 21, 2011 | Samsung Televison & Video

1 Answer

LCD TV makes buzzing sound. Why?


You are dealing with a failing backlight inverter. You are hearing the surface mount components failing over time and that buzz is them not keeping up with the voltage coming into them. (Hz) You will need to open the tv and locate the noise and replace the backlight inverter :)


Please rate if this helped :D

Mar 08, 2011 | Samsung UN55B8000 55 in. LCD HDTV

Not finding what you are looking for?
Televison & Video Logo

Related Topics:

1,324 people viewed this question

Ask a Question

Usually answered in minutes!

Top Televison & Video Experts

The Knight
The Knight

Level 3 Expert

74617 Answers

Donald DCruz
Donald DCruz

Level 3 Expert

17130 Answers

Electro Med Services...
Electro Med Services...

Level 3 Expert

6694 Answers

Are you a Televison and Video Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...