Samsung LE32R88BD/ BN44-00155A

[tom66]

Re: Samsung LE32R88BD/ BN44-00155A

Try heating power board and main board to see if fault is temperature related, most likely it is.

[Visant]

Re: Samsung LE32R88BD/ BN44-00155A

Hello bad caps forum , i am lurking forum and successfully getting solutions for years. but now i don't know what to do . I have in my life modded some video game consoles from megadrive/genesis to playstation 3 for more pleasant home use

I have this TV since 2009 and it worked perfectly till 3 days ago . It turns on and turns off back light after 2-30 seconds . I have read that main problems are RM801 and CM810 parts but in my case they look great . Any suggestions ?

[budm]

Re: Samsung LE32R88BD/ BN44-00155A

Lets find out first if the BL_ON signal and 24VDC are present at the inverter connector when the backlights go off. There should be some labelling close to the connector to identify the pins on the inverter connector. I do have a feeling that you may have bad inverter transformer.

[Visant]

Re: Samsung LE32R88BD/ BN44-00155A

I just measured between GND and VAC on inverter board connector and it says 24.4V steady.

But between GND and ON/OFF it varies between 0V and 5.25V very randomly

[budm]

Re: Samsung LE32R88BD/ BN44-00155A

"GND and VAC" You mean DC? I expect the ON/OFF pin to have >3VDC and steady, this signal is generated by the main board. What you can do is to disconnect this wire between the main board and the inverter board (we do not want to back feed the signal back into the man board), then use 1K resistor between the ON/OFF pin of the inverter board and the 5V Standby by to force on the backlights, they should stay on.

[Visant]

Re: Samsung LE32R88BD/ BN44-00155A

"GND and VAC" You mean DC?

I mean pin marked " VCC" on inverter board

I expect the ON/OFF pin to have >3VDC and steady, this signal is generated by the main board. What you can do is to disconnect this wire between the main board and the inverter board (we do not want to back feed the signal back into the man board), then use 1K resistor between the ON/OFF pin of the inverter board and the 5V Standby by to force on the backlights, they should stay on.

Ok,where do i find 5V stanby feed ?

[budm]

Re: Samsung LE32R88BD/ BN44-00155A

CNM801 pin3 on the power supply board, it is 5.2VSTBY. YYou should download the diagram for the power supply board, see post 25.

[Visant]

Re: Samsung LE32R88BD/ BN44-00155A

Found it !
I just did that , it works fine for now . Thanks !
So the problem was in power board ?

[Visant]

Re: Samsung LE32R88BD/ BN44-00155A

I don't know how to edit post above so i'm doubleposting ...

TV back light now shuts down in about 20 minutes ,just second before back light shuts down i hear 1 second noise from inverter . i took a picture of capacitors on the board ,i don't know their value so i am not happy about taking them off because i don't know if they are available in my electronics store

Inverter is marked l315B1-16A

i found out that the capacitor value is 270uF 35V

[tom66]

Re: Samsung LE32R88BD/ BN44-00155A

Check 24V to inverter is stable.

[Visant]

Re: Samsung LE32R88BD/ BN44-00155A

Constant 24.3V When backlight on .It has been 2 hours and still no sudden backlight off situations

[PeterOnline]

Re: Samsung LE32R88BD/ BN44-00155A

Perfect. I had the same issue and solved it according your description below. Thank you for this post.

Take a pat on the back Mr retiredcaps.
Your observations appear to be correct in a round about way.

When you referred to BN44-00192A (instead of BN44-00155A)
I was puzzled and assumed you had got some threads crossed and took little notice of your comments.

I can know see I had posted the wrong image (of a BN44-00192A),
which I must have downloaded in my research. The two boards look remarkable similar, (maybe just a different Europe/ US designation}.

The point is, I decided to check the board again visually. I noticed a faint black line on the circuit board where the yellow adhesive fixes blue capacitor CM810,(44nf 1KV) to it.I figured that if this was some sort of leaky conduction path across the capacitor lead out wires it was capable of passing enough current to blow safety resistor RM801.

After chopping away a the adhesive and removing the capacitor I scraped away the (carbonated?) black line, (track). With capacitor reinstalled and a new resistor in place, TV was back in business. It's still early days yet, (two), but as the theory appears sound, I am quietly confident.

As an extra precaution, I have removed adhesive from around other components where a leaky path could develop.

Attachments show actual board BN44-155A and problem area before and after capacitor removal.

[tetetete]

Re: Samsung LE32R88BD/ BN44-00155A

Estoy buscando el listado de componentes y sus valores de la fuente BN44-00155A v. 1.2 de un samsung LCD modelo : LE32R86BD , Code : LE32R86BDX/XEC Type : BP32E0.¿ Alguien me prodria ayudar ?.No tengo camara para sacarle fotos a la placa , mas tarde intentare sacarlas con la web cam y luego las subire a Imgur.Saludos desde Tenerife -Canarias y muchas gracias por vuestra ayuda .

[johnboy1313]

Re: Samsung LE32R88BD/ BN44-00155A

Estoy buscando el listado de componentes y sus valores de la fuente BN44-00155A v. 1.2 de un samsung LCD modelo : LE32R86BD , Code : LE32R86BDX/XEC Type : BP32E0.¿ Alguien me prodria ayudar ?.No tengo camara para sacarle fotos a la placa , mas tarde intentare sacarlas con la web cam y luego las subire a Imgur.Saludos desde Tenerife -Canarias y muchas gracias por vuestra ayuda .

Translated with Google Translate...
"I'm looking for the list of items and their values BN44-00155A v source. 1.2 of a Samsung LCD model LE32R86BD, Code: LE32R86BDX/XEC Type: BP32E0. Prodria anyone help me?. I have no camera to take pictures of the board, will try them out later with the web cam and then I'll upload to Imgur. Greetings from Tenerife, Canary Islands and thank you very much for your help."

Yo no hablo mucho español, por favor, perdona mi mal escrito. Estoy utilizando Google para traducir. He traducido el mensaje de Inglés. Vamos a ver si alguien me puede ayudar. Mientras tanto, por favor ver el post número 31. Puede tener la información que busca.

[tetetete]

Re: Samsung LE32R88BD/ BN44-00155A

Muchas gracias johnboy1313 por tu ayuda , ahora mirare lo del post 31 que me indicas.

[budm]

Re: Samsung LE32R88BD/ BN44-00155A

sch from tom66
http://www.toms-service-manuals.com/

[tetetete]

Re: Samsung LE32R88BD/ BN44-00155A

Muchas gracias tambien a budm , estoy comprobando la correspondencia del 2º esquema , MK32P(DLC32P) SMPS (MULTI ) , con los componentes de mi BN44-00155A v.1.2 y de momento coinciden. Esta es una imagen de mi fuente que he encontrado en la red , es identica a la mia en relacion a los componentes :

Saludos.

Editado : desconectando todos los cables menos el de alimentacion de 220v , he comprobado el voltaje en el jumper JP845 y este oscila entre 0v , 12v , y 24v aproximadamente , ¿ Teneis idea de que componentes pueden estar fallando ?.

Muchas gracias.

[budm]

Re: Samsung LE32R88BD/ BN44-00155A

I used Google Translate but do not quite understand the voltage readings.
Picture courtesy of Shop Jimmy.

[tetetete]

Re: Samsung LE32R88BD/ BN44-00155A

Picture courtesy of Shop Jimmy.

Muchas gracias por la imagen , se ve excelente.

[polishelvis]

Re: Samsung LE32R88BD/ BN44-00155A

1. Have a LNT 3242 with BN44-00155A that goes into protection mode, backlights flash
for two seconds then backlights shutdown, power is still on. Looks like the controller
board is detecting a fault or low voltage and going into protection mode. Suspect the
problem is low voltage on the 13 volt supply.

2. The 13 volt power supply only reads 11.58 volts right from power up BEFORE
the backlight is even enabled.

3. All other supply voltages are correct, 3.4, 5.3, 5v STBY, and 24 volt bus to
backlight is good even when the backlight is enabled for two seconds.
12 volt supply looks to be linear regulator of the 13 volt bus so that matches
the 11.58 input.

4. Okay replaced the seven electrolytics on the outputs. RM801 looks good, removed
the glue any way and ohmed it out. All remaining caps look great. No other damage.
Examinied the transformers, look good, examined the 13 volt feedback loop that
looks good as well. no sign of heating or damage on the other boards.
Inverter also looks good, caps on the inverter is good as well.
Unplugged and tested each of the backlight lamps one at a time
and the set still goes into protection mode.

5. Any suggestions as to why the 13 volt supply is only around 12 volts?
The same transformer is used for the 24 volt supply and that measures a solid 24.2
even under load when the all backlights are briefly turned on. Diodes on the
13 volt supply measure good as well.

Thank You