Service Manual for Samsung la40r81bd LCD

[blacki]

Hi,
I have a LA40M81BDX/XSA that died with the capacitor issue in March. First symptom was powering itself on overnight. I bought a new set then and just now got around to fixing the Samsung as an alternative to leaving it out on the street. I changed the swollen 2200uF 10V caps on the 5.4V output and the 1000uF 16V caps on the 13V output. No difference, still relay clicking. I replaced the 1000uF 10V cap on the 5.2V standby. I probed on connector 801. All the voltages were good, with no ripple. I did notice that the relay never dropped before the LED in the optical connector turned on. That was the only sign of life. I replaced every other electro on the power board. That didn't help either. At this point I gambled on a new power board, ordered BN44-00165A but received BN44-00167A, plugged it in, same symptoms. So far I'm down around $150, worthwhile to save a TV that cost nearly $2000.
Then I found this forum, soldered a wire to pin 5 (serial data) of IC1803, plugged everything back in, grounded the wire, applied power and saw the snowy analogue display. Same with the original power board after I reinstalled it. So I need a new eeprom. Electronics Market has part number 1103-001385 for $6.90, seems reasonable.

The new board is not genuine Samsung, but Hansol brand, made in Thailand with a different circuit board layout, and the odd component left off, maybe to reduce cost. Although the electrolytic caps are the same infamous Sanwha brand, they are physically different and larger. There are no 2200uF caps on the 5.4V, but a trio of 1000uF 10V. The 13V has a pair of 1000uF 25V caps, but they are different diameters, intentionally, since the board markings have corresponding diameters. I don't know why they are different. Both boards have 1000uF 10V on the 5.2V STBY.

So I have a few questions.
Is the eeprom actually broken, or does it just contain corrupted data (presumably caused by ripple on the 5.4V)
Does the genuine Samsung eeprom P/N 1103-001385 contain the correct, or mostly correct data, or is it blank?
Are the Sanwha caps on BN44-00167A known to fail like the ones on the genuine Samsung power boards?
All the discussion on the forum implies that replacing an 8 pin surface mount IC is routine. I can hardly even see the chip. How do I remove the old one, melt all 8 solder pads at the same time, or 4 of them anyway? I did see the hint about reflowing the unleaded solder with leaded.

Thanks very much for the forum. I could find only vague hints about the eeprom anywhere else. Now I can leave the old Sony CRT out on the street.

Ian

[blacki]

I found post #106 explaining how to lift the pins one at a time, so with a strong light and magnifying glass I may be able to learn some microsurgery skills. I see all the pictures and links in the forum now. I couldn't when I wrote the previous post. The link to the service manual in post #77 no longer works. Is the manual available anywhere?

Ian

[blacki]

I found a service manual for the LA40M81BDX/XSA for USD25 at manualzone, but ended up not needing it. I realized I could select the digital menu and change channels. When I plugged in the aerial it worked perfectly, all settings still OK. I did not need the service menu. So I was lucky, all it needed after the caps were replaced was a few power cycles with IC1803 pin 5 grounded. The data in the eeprom was intact. I could have fixed it for the cost of 2 caps.
It doesn't look as if anyone has looked at this forum for 6 months, but thanks anyway.

Ian

[mickstv]

Just in case it dies again, you can us a generic 24C256- 256kb. The micro writes data to the eeprom when first turned on.

If you do need to replaced the eeprom, let me know and I'll post up the service mode changes that need to be made.

[traderdesk]

Just in case it dies again, you can us a generic 24C256- 256kb. The micro writes data to the eeprom when first turned on.

If you do need to replaced the eeprom, let me know and I'll post up the service mode changes that need to be made.

Can I use this eeprom "seiko instruments - s-24c256ci-j8t1u4 - eeprom, 256kbit, 2-wire, 8sop" to replace the original Samsung Eprom IC 24C256BN (1103-001385) or do I need the original 24c256BN???

Thanks...

[Elfchris]

Hi guys,

My future mother in law connected a media player that we gave her for Christmas to one of the HDMI ports on the rear which shut down the tv and sent the power supply into the familiar clicking mode. She did this while the TV was still on but somehow that was my fault ... lol

Anyway on opening up the back I found that the HDMI decoder was fried, you could cook an egg on it (a very small egg). I replaced the chip which allowed the TV to fire up but once it did it then shut back down. I replaced the eeprom (just in case) which changed the way it fired up but I still can't get it to show a picture before it shuts down again. I haven't replaced anything on the power supply yet but I'm assuming I shouldn't have to ( yes I'm sure that's what it will be ... lol).

What I am getting is the standby led flashing at me and sometimes the blue light on the bottom doing the same. It seems to me that something else maybe fried and I may have to try and find a replacement main board. Any thoughts? Dos anyone have the service manual? Does anyone have a main board? I'm desperate to fix it. Personally I'd throw it out but the dragon lady wants it fixed!

Cheers.

[mickstv]

Check for bulged electrolytic caps on the power supply board. Is your's the same model as the original poster, if not please post your model and I'll see if I still have the manual.

[ltindustries]

Here's another copy of the repair guide in Exel format.






Mick

file no longer available on media fire, please would you kindly repost the file. Great thread. I really need this and have just signed up to forum.

Many thanks and kind regards.

[tristen]

10 seconds with Google indicates that there is one available for download at the scribd website.

It's definitely there because I checked.

[gtpcarshare]

SORRY MICKSTV I was just trying to help being a samsung service agent and not seen the post you sent cos not bean a member long

I make changes to the model option, panel size under service menu and my friend insisted on changing other setting ( EDID was set to 1660x900 or something - higher than the TV original setting ot 1366x768 , we did this, after I read about resetting EEPROM procedure using service menu changes. The TV was on when I unplugged the power. My Samsung LCD is series 4 from 2008 ( LA32A450 ), it had some issues after several power outage, maybe corrupted EEPROM ? Sometimes it won't turn on, ie the tv red LED only blinks with remote control commands and the buttons on the side bezel won't respond and I have to unplug and plug numerous times until it turns on. The only way to avoid this, is to unplug with the TV running ( on ). I can turn off and turn on the tv just fine with remote as long as there's no power outage while the tv was off.

After lots of reading, I decided to reset the EEPROM via physical means, I tried to find which EEPROM chip needs to be shorted ( pin 5 + 6 ) .... Do you have any clue which chip ? I saw one near the tuner metal assembly, it has ST brand ( IC2003 ), while another one near the VGA port has the little dot indentation on lower left corner with 2015 marking ( IC3008 ). These are the only 2, in the underside of the main board there are several more ( one of them is IC1012 - pin5 and 6 are connected with a resistor ). I need to know which one to short Any clue what's the serial number for the EEPROM chip on LA32A450 ?

Right now the TV is not turning on, when connected to main, the red LED will blink for about 5 seconds ( like usual when turning on ), but it failed to turn on ( display is blank and no sound ), and keep on repeating the cycle.

[best4less]

Wow back again

I got one with no power at all

Replaced the usual caps and still no power or lights

Anything to check before I get me old meter out and really fark it up LOL

Cheers

[Moof]

I know this is an old thread but I have just repaired one of these. New caps and eeprom. All is great except when I watch sport and they have scores and info at the bottom of the screen half of the info is missing.
Does anyone know how to shrink or move the picture up?
I have selected the right panel and size in service menu and cannot find anything that adjusts the size or position of picture.
Any help would be great
Cheers

[vk4lw]

I have one of these LA32R81's. It is doing the on standby cycle thing. I have replaced all of the large caps except for the big one, but that looks ok as it is not bulging like the others were. I replaced the eeprom and it fired into life. I didnt change any of the service menu setting and 20 minutes later it turned off and repeated it's original problem. I can't get it to go back into the service menu with "INFO, MENU, MUTE, Power ON"

So I replaced the eeprom again and no luck. I then removed the eeprom completely and tried. It wont turn on with no eeprom.

So I am a bit stuck.

Checking the voltages from the power supply seems so give me weird results. The voltages don't seem to be stable. They all vary from 0 to their respective voltages over few second cycle.

Pulling my hair out with this one.

Anyone seen this before?

Thanks.