Sony KDL-40s4100 No Picture/Sound/Backlight

[selldoor]

Re: Sony KDL-40s4100 No Picture/Sound/Backlight

Ok Power off for 5 Minutes can you unplug the connector at the top right (In your picture)
meter on ohms 2000 check the resistance across the connector pins.

Did you try unplugging and replugging the connector mentioned by
1978 mustang

[aquaangel]

Re: Sony KDL-40s4100 No Picture/Sound/Backlight

Ok Power off for 5 Minutes can you unplug the connector at the top right (In your picture)
meter on ohms 2000 check the resistance across the connector pins.

Did you try unplugging and replugging the connector mentioned by
1978 mustang

i tried that harness according to mustang and the problem was still there, Now i disconnected that top right harness, where do you want me to take ohms readings? pins from where to where?
to the PWr supply or the A/V board?

Thanks

[aquaangel]

Re: Sony KDL-40s4100 No Picture/Sound/Backlight

Here are the readings in Ohms / from the pwr supply board
1- 827
2- 846
3- 4.8
4- 4.8
5- 794
6- .1
7- 246
8- 246
9- 245
10- 0
11- 0
12- 0
13- 246
14- 0

[aquaangel]

Re: Sony KDL-40s4100 No Picture/Sound/Backlight

Here are the readings in Ohms / from the pwr supply board
1- 827
2- 846
3- 4.8
4- 4.8
5- 794
6- .1
7- 246
8- 246
9- 245
10- 0
11- 0
12- 0
13- 246
14- 0

WOW, let's do that again, i had the wrong voltmeter earlier to read my resistance. i found my old one now
so Here are the REal readings:
1- 1.66 K
2- 1.66 k
3- .005
4- .006
5- 1.25 k
6- .001
7- .48
8- .48
9- .48
10- .001
11- .001
12- .001
13- .765
14- .001

Sorry about the previous readings.

[selldoor]

Re: Sony KDL-40s4100 No Picture/Sound/Backlight

Sorry for wasting your time I should have said top left The one from the transformer to the inverter.
Everyone reading will have wondered what did he ask that for!!

[aquaangel]

Re: Sony KDL-40s4100 No Picture/Sound/Backlight

Sorry for wasting your time I should have said top left The one from the transformer to the inverter.
Everyone reading will have wondered what did he ask that for!!

Reading .06 k ohms from the Pwr supply board.

[aquaangel]

Re: Sony KDL-40s4100 No Picture/Sound/Backlight

Reading .06 k ohms from the Pwr supply board.

Sorry, anything about it? just wondering if that tv is worth to fix or not.

[rayrod81]

Re: Sony KDL-40s4100 No Picture/Sound/Backlight

Your power supply is fine. This is a common problem on this model. The main board is the culprit. Not sure what the exact problem is on the main board but I suspect bad solder joints on the board. I could not find any other issue on the board and do not have a proper reflow station to go that route.

I have had a couple of these with this problem and both times a new main board (A board) fixed them. The issue is that the A Board is hard to find below $100 and the part has to match to the TV. There were at least two different panels and A Boards used in this model and they are not compatible with eachother.

[aquaangel]

Re: Sony KDL-40s4100 No Picture/Sound/Backlight

Thanks, looks like it is the A board from this end as the back light does flicker when i disconnect CN303, i will see if that is worth fixing with a good price for the board, or else it will have to go for recycling. ;-)
the only thing i like about this tv is the fact that it has a 1080P, too bad it is a 40" as mine is 42" but doesn't have the 1080p as it has the 1080i on a Light grey background screen as the Sony is black which i also like.

unless you guys have one for sale around?

Thanks Again

[aquaangel]

Re: Sony KDL-40s4100 No Picture/Sound/Backlight

I decided to go for it anyway, will order the part next month with a total of 238.XX bux for the new board. looking forward to see it in action.

[handycap]

Re: Sony KDL-40s4100 No Picture/Sound/Backlight

Hi, guys.. I need your help..
I have sony kdl-52lx900, first my tv turn on with the green light but no picture no sound but sony logo light up, after 1 minutes my tv turn off and turn on straight away again and again, so i tried to reflow the chip of the mainboard with heat gun i thought i saw smoke from the main board, i put the mainboard to the tv and connect everything, now my tv blink 3 time standby light, like standby light blink 3 times pause standby light 3 time pause....please for your help guys...

Thanks so much

[budm]

Re: Sony KDL-40s4100 No Picture/Sound/Backlight

This thread is for "Sony KDL-40s4100"
You have "kdl-52lx900" Start a new thread with your model number.

[OldMan]

Re: Sony KDL-40s4100 No Picture/Sound/Backlight

My KDL-40S4100 set is experiencing some issues but a bit dissimilar from what was described above.

What I have - all normal voltages coming from PSB to main following those printed next to C301-303. I am able to get sound but no picture on any input. I DO have a backlight visible and the inverter shows no signs of failure.

In addition to having no picture, the set turns off after 1-2 minutes of use (with audio only). There is a slight hum coming form the power board which makes me think it is no good. I'm leaning towards replacing this board as it is quite cheap at the moment.

Any opinions?

[vinceroger69]

Re: Sony KDL-40s4100 No Picture/Sound/Backlight

test any fuses you can find on the t conn board test for dc voltage each side of the fuse if you cant locate them post a good clear picture of the t conn board

[OldMan]

Re: Sony KDL-40s4100 No Picture/Sound/Backlight

I was able to locate one fuse -- it measures 0V on one side and 11.56V on the other. If needed/helpful I can post another picture to provide reference.

[vinceroger69]

Re: Sony KDL-40s4100 No Picture/Sound/Backlight

so it looks like the fuse has failed for some reason are there any markings on it or printed by it

[OldMan]

Re: Sony KDL-40s4100 No Picture/Sound/Backlight

Lots of markings -- attached a photo to see what I'm looking at. FP1 was where I had 0 on left and 11.56 on right side.

[OldMan]

Re: Sony KDL-40s4100 No Picture/Sound/Backlight

Just stumbled across this thread which nicely sumps up my issues.

https://www.badcaps.net/forum/showthread.php?t=20956

[vinceroger69]

Re: Sony KDL-40s4100 No Picture/Sound/Backlight

Lots of markings -- attached a photo to see what I'm looking at. FP1 was where I had 0 on left and 11.56 on right side.

so its a 3 amp im not too sure to be honest how to check the tconn for shorts etc lets see if one of the more experienced members will chime in with some resistance checks you can do failing that are replacements tconn boards cheap?

http://www.ebay.co.uk/sch/i.html?_sa...2LV2.4&_sop=15

[OldMan]

Re: Sony KDL-40s4100 No Picture/Sound/Backlight

Appreciate the help, vinceroger69. I knew they were very cheap so I might go ahead and just replace the board hoping it fixes the issue.